Wednesday, November 21, 2007

“Noah’s flood” spread farming, researchers say

I find the issue interesting how scientists can link the flood and agriculture.
I should say this link may also be there, why do we have a lot of
biodiversity in the tropical areas where they fall into the belt of this
flood as well. Is the Noah's issue also not connected with conservation
of biodiversity when they keep all animals male and female into
the craft??

Read On and do not shoot the messenger, but thought provoking ehh.

Hastings
===========

Nov. 19, 2007World Science staff

http://www.world-science.net/othernews/071119_flood.htm

A giant pre­his­tor­ic flood—which a con­tro­ver­sial the­o­ry has linked to the Bib­li­cal sto­ry of Noah’s Ark—kick-started Eu­ro­pe­an ag­ri­cul­ture, ac­cord­ing to a new stu­dy.A decade-old the­o­ry holds that about 7,500 years ago, a del­uge filled the Black Sea in the Mid­dle East, in­spir­ing the Noah’s Ark flood tale and pos­sibly some of the oth­er flood sto­ries that mys­te­ri­ously re­cur in many myth­o­lo­gies.

Al­though some re­search­ers dis­pute the the­o­ry, the new stu­dy’s au­thors take it fur­ther and say the dis­as­ter al­so trig­gered a boom in ag­ri­cul­ture. “A cat­a­stroph­ic rise in glob­al sea lev­el led to the flood­ing of the Black Sea and drove dra­mat­ic so­cial change across Eu­rope,” the sci­en­t­ists said in an an­nounce­ment of their find­ings.

The del­uge “could have led to the dis­place­ment of 145,000 peo­ple,” they ex­p­lained. “Ar­chae­o­log­i­cal ev­i­dence shows that com­mun­i­ties in south­east Eu­rope were al­ready prac­tis­ing early farm­ing tech­niques and pot­tery pro­duc­tion be­fore the Flood. With the cat­a­stroph­ic rise in wa­ter lev­els it ap­pears they moved west, tak­ing their cul­ture in­to ar­eas in­hab­it­ed by hunter-gatherer com­mun­i­ties” across Eu­rope.The re­search, by the Un­ivers­i­ties of Ex­e­ter, U.K. and Wol­lon­gong, Aus­tral­ia, ap­pears in the Sep­tem­ber is­sue of the re­search jour­nal Qua­ter­nary Sci­ence Re­views.The trig­ger for the hy­poth­e­sized flood would have been the col­lapse of the North Am­er­i­can Ice Sheet some 8,000 years ago, ac­cord­ing to the sci­en­tists.

This would have raised sea lev­els—causing wa­ter to vi­o­lently breach the Bos­po­rus Strait, which pre­vi­ously dammed the Med­i­ter­ra­nean and kept the Black Sea as a freshwa­ter lake.The Aus­tral­ian and U.K. re­search­ers cre­at­ed re­con­struc­tions of the Med­i­ter­ra­nean and Black Sea shore­line be­fore and af­ter the hy­poth­e­sized sea lev­el rise.

They es­ti­mat­ed that nearly 73,000 square km of land, an ar­ea about the size of Ire­land, was lost to the sea in one 34-year pe­ri­od.Con­tro­ver­sy has dog­ged the flood hy­poth­e­sis from the start, al­though it has sup­port from ev­i­dence in­clud­ing signs of hu­man hab­ita­t­ion found well be­neath the sea. One team has pro­posed that al­though there was a flood, it hap­pened too grad­u­ally to threat­en an­y­one, and thus can­not ex­plain the del­uge myths.

Anoth­er sci­ent­ist has claimed that the true source of these ta­les is the pres­ence of ma­rine fos­sils in moun­tains: the fos­sils get there by ge­o­log­ic pro­cess, but an­cient peo­ple might have seen them as proof of past floods.The au­thors of the Qua­ter­nary Sci­ence Re­views pa­per are stick­ing close to the ori­gi­nal del­uge hy­poth­e­sis, pro­posed by ma­rine ge­ol­o­gists Wil­liam Ryan and Wal­ter Pit­man in 1996. “Peo­ple liv­ing in what is now south­east Eu­rope must have felt as though the whole world had flood­ed.

This could well have been the or­i­gin of the Noah’s Ark sto­ry,” said the Un­ivers­ity of Ex­e­ter’s Chris Tur­ney, lead au­thor of the new pa­per. “En­tire coast­al com­mun­i­ties must have been dis­placed, forc­ing peo­ple to mi­grate in their thou­sands. As these ag­ri­cul­tur­al com­mun­i­ties moved west, they would have tak­en farm­ing with them across Eu­rope. It was a rev­o­lu­tion­ary time.”* * *

Monday, November 19, 2007

HOW CAN WE TALK OF LAKE MALAWI BIODIVERSITY WHEN THE WORLD IS BURNING

The world report explicitly said it all, we need to work hard to conserve the biodiversity through our reduction of green house gases. As environmental scientists lets formulate our research questions to help policy makers, come out with informed decisions on whats to need be done to save this burning planet from green house gases.

Lead on the report:
=============================

Scientists paint dire picture of hotter life on Earth

Final U.N. report more alarming than predecessors

By ELISABETH ROSENTHALTHE NEW YORK TIMES

VALENCIA, Spain -- In its final and most powerful report, a U.N. panel of scientists describes the mounting risks of climate change in language that is more specific and forceful than its previous assessments, according to scientists here.
Synthesizing data from its three previous reports, the U.N. Intergovernmental Panel on Climate Change for the first time specifically points out what is risked if governments fail to respond: melting ice sheets that could lead to a rapid rise in sea levels and the extinction of large numbers of species brought about by even moderate amounts of warming, on the order of 1 to 3 degrees.
The report carries heightened significance because it is the last word from the climate panel before world leaders meet in Bali, Indonesia, in December to begin to discuss a global climate change treaty that will replace the Kyoto Protocol, which expires in 2012. It is also the first report from the panel since it shared the Nobel Peace Prize with Al Gore in October -- an honor that many scientists here said emboldened the panelists to stand more forcefully behind their positions.
"This document goes further than any of the previous efforts," said Hans Verolme, director of the World Wildlife Fund's Global Climate Change Program. "The pressure has been palpable -- people know they are delivering a document that will be cited for years to come and will define policy."
The previous three sections, released between February and April, focused on one issue at a time: the first on science, the second on how the world could adapt to warming, the third about how countries could "mitigate," or reduce, the greenhouse gases produced.
This fourth and final assessment -- the so-called synthesis report -- seeks to combine lessons from all three. Its conclusions are culled from data contained in the thousands of pages that were essentially technical supplements to the panel's previous publications. How that data is summarized and presented to the world will be a powerful guide to what the scientists consider of utmost importance at the end of a five-year process, offering concrete guidelines for policymakers.
"You look to a synthesis report to provide clarity, to clarify what was obscure in previous reports," said Michael Oppenheimer, a climate scientist at Princeton University. "Now, how can we take these findings and formulate a policy response that's quick enough and big enough?"
Even though the synthesis report is more alarming than its predecessors, some researchers believe that it still understates the trajectory of global warming and its impact. The IPCC's scientific process, which takes five years of study and writing from start to finish, cannot take into account the very latest data on climate change or economic trends, which show much more development and energy use in China.
"The world is already at or above the worst-case scenarios in terms of emissions," said Gernot Klepper of the Kiel Institute for World Economy in Kiel, Germany. "In terms of emissions, we are moving past the most pessimistic estimates of the IPCC, and by some estimates, we are above that red line."
The panel presents several scenarios for the trajectory of emissions and climate change. In 2006, 8.4 gigatons of carbon were put into the atmosphere from fossil fuels, according to a study in the proceedings of the National Academy of Science, which was co-authored by Klepper. That is almost identical to the panel's worst-case prediction for that year.
Likewise, a recent International Energy Agency report looking at the unexpectedly rapid emissions growth in China and India estimated that if current policies are not changed, the world would warm 6 degrees by 2030, a disastrous increase far higher than the panel's estimates of 1 to 4 degrees by 2100.
While the United States, Saudi Arabia and China tried to change the text in order to downplay the consequences of global warming, developing nations -- which will bear the initial brunt of climate change -- were much more forceful than at previous meetings in opposing these efforts, according to a scientist who was in the negotiating room. "I suspect that will continue," he said.
One novel aspect of the report is a specific list of "Reasons for Concern." It includes items that are thought to be very likely outgrowths of climate change that had been mentioned in previous reports, such as an increase in extreme-weather events.
But for the first time it includes less-likely but more-alarming possibilities, such as the relatively rapid melting of polar ice. Previous reports focused more on changes the scientists felt were "highly likely."
"This time they take a step back and look at the totality," Verolme said. "Saying it is less likely to occur, but if it does, we are fried."
One such area is the future melting of ice sheets in Greenland and western Antarctica. In earlier reports, the panel's scientists acknowledged that their computer models were poor at such predictions, and did not reflect the rapid melting that scientists have recently observed.
If these areas melt entirely, seas would rise 40 feet, scientists said. While scientists are certain that the sheets will melt over millennia, producing elevated sea levels, there is now evidence to suggest that it could happen much faster than that, perhaps over centuries.
"In my view, that would make it not just difficult, but impossible to adapt successfully; some of my colleagues would say catastrophic," said Oppenheimer.
This final report also puts more emphasis on the ripple effect of small degrees of temperature change, some of which are already being seen, such as species extinctions and loss of biodiversity.
"A relatively modest degree of warming -- 1 to 3 degrees -- spells a lot of trouble, and I think that was not clear in the previous report," Oppenheimer said.
He said part of the reason for the lack of clarity was that governments had "messed around" with the language and structure of the report during the approval process.
This time around, the consequences of different degrees of climate change will be better laid out so that the ministers who meet in Bali in December will understand the options and the consequences of inaction. "This should light a fire under policymakers," Oppenheimer said.

Wednesday, November 14, 2007

NATURAL HUMAN HISTORY REVISITED

Hi Guys

As scientists keep on looking for more evidence of evolution in human
history, one breaking moment brings them back to africa, yes the
great east africa rift valley of which Malawi is well positioned as
the epicenter of human evolution.

However, the dates are much more older than the Lake Malawi formation
dating of 1 million years ago. So may be this ape named Nakalipithecus nakayamai,
did not drink water or feed nuts irrigated from the fesh waters of Lake Malawi.
Nakalipithecus nakayamai is said to be 10 million years old.

The questions is which ape coevoluted with the maginificent lake malawi,
will be left to those who fancy the Lake Malawi cichlids and their
biodivesity, so go figure.

Hastings
================

Experts find jawbone of pre-human great ape in Kenya

By Katie Nguyen Reuters - Tuesday, November 13 03:43 pm

NAIROBI (Reuters) - Researchers unveiled a 10-million-year-old jaw bone on Tuesday they believe belonged to a new species of great ape that could be the last common ancestor of gorillas, chimpanzees and humans.

The Kenyan and Japanese team found the fragment, dating back to between 9.8 and 9.88 million years, in 2005 along with 11 teeth. The fossils were unearthed in volcanic mud flow deposits in the northern Nakali region of Kenya.

The species -- somewhere between the size of a female gorilla and a female orangutan -- may prove to be the "missing link", the key step that split the evolutionary chains of humans and other primates, Kenyan scientists said.

"Based on this particular discovery, we can comfortably say we are approaching the point at which we can pin down the so-called missing link," Frederick Manthi, senior research scientist at the National Museums of Kenya, told reporters.

"We have to find more fossils from a cross-section of sites to sustain that particular theory," he added, speaking at a desk where the approximately four-inch sliver of bone was displayed alongside human and gorilla skulls.

It was the latest important finding in east Africa's Rift Valley -- a region long regarded as the "cradle of humankind".

"The teeth were covered in thick enamel and the caps were low and voluminous, suggesting that the diet of this ape consisted of a considerable amount of hard objects, like nuts or seeds, and fruit," Yutaka Kunimatsu at Kyoto University's Primate Research Institute said in a telephone interview.

"It could be positioned before the split between gorillas, chimps and humans," he added.
However, it was hard to determine what the new species, named Nakalipithecus nakayamai, looked like.

"We only have some jaw fragments and some teeth ... but we hope to find other body parts in our future research. We plan to go back next year. We will try to find bones below the neck to tell us how the animal moved," Kunimatsu said.

Published in the latest issue of the Proceedings of the National Academy of Sciences, the finding is significant as it gives credence to the theory that the evolution from ape to man may have taken place entirely in Africa.

Prior to this finding, there had been so little fossil evidence in Africa dating between 7 to 13 million years ago that some experts began to surmise that the last common ancestor left Africa for Europe and Asia, and then returned later.

"Now, we have a good candidate in Africa. We do not need to think the common ancestor came back from Eurasia to Africa. I think it is more likely the common ancestor evolved from the apes in the Miocene in Africa," Kunimatsu said.

The Miocene is a period extending from 23.03 million to 5.33 million years ago.
"Some apes (then) left Africa and migrated to Eurasia. They then became orangutans in Southeast Asia. Today's orangutan evolved from the apes that left Africa," he said.

Wednesday, November 7, 2007

Technique lets scientists see brain in full color


Hi Friends,


Last week it was a fast genetic mice and today its a brain colouration.


With all this fast evolving molecular technologies, why should other

people go about hungry day in day out simply becasue they missed,

the green revolution which saw the increase in food production in

the latin america and east asia.


While, I partly understand the mismatch overlooked in the food patterns

of the crops targeted in green revolution and the satple foods of sub-sahara.

These new technologies will or may equally provide the fast growing and

high yeilding crops of sub-sahara. Yes, we use our maize and cassava not

wheat and rice as promoted by the green revolution.


As a molecular biologists and concerned citizen of the underprivilaged, I

propose that scientists in this region should take the molecular techniques

seriously and think of ways how to improve the comonly used food crops,

to revolutionise the growth and productivity of these food crops.


Hastings

==========


Take note that the picture and story are credited to Nature and World science staff.
Nov. 6, 2007 Courtesy Nature and World Science staff
http://www.world-science.net/othernews/071106_braincolor.htm

With a com­bina­t­ion of ge­net­ic tricks and fan­cy pro­teins, re­search­ers have col­ored hun­dreds of in­di­vid­ual cells in a mouse brain with dis­tinc­tive hues. This pro­vides a key step to­wards un­der­stand­ing how the nerv­ous sys­tem works, both nor­mally and in dis­eased brains, sci­en­tists said.


The re­search, pub­lished in the Oct. 31 is­sue of the re­search jour­nal Na­ture, takes brain map­ping to a new lev­el, and re­sults in the la­bel­ling of nerve cells with ap­prox­i­mately 90 dif­fer­ent co­lour com­bina­t­ions.


Over a hun­dred years ago, the Span­ish phy­si­cian Ra­mon Y Ca­jal opened the gates to mod­ern neu­ro­sci­ence with a tech­nique that col­ors nerve cells so their struc­ture is clearly vis­i­ble, called Gol­gi stain­ing.


But it uses only one col­or, and un­til now it has re­mained dif­fi­cult to map out in­di­vid­ual cells in each brain cir­cuit. In the new re­search, Jeff Licht­man of Har­vard Un­ivers­ity in Mas­sa­chu­setts and col­leagues de­vel­oped a technicol­or ver­sion of Gol­gi stain­ing, called “Brain­bow,” that they said al­lows more de­tailed re­con­struc­tions of brain cir­cuits

Saturday, October 13, 2007

Species extinctions still rising, experts warn

‘Red List’ grows to 16,306 animals and plants seen as threatened

The full Red List database is online at iucnredlist.org.

MSNBC staff and news service reports
Updated: 10:50 a.m. ET Sept. 12, 2007

Nearly 200 animals and plants have been added to a global database of threatened species, the World Conservation Union announced Wednesday, adding that the number is certainly on the low end.

From the lowland gorillas of Africa to corals of the Galapagos Islands, more than 16,300 species are threatened with extinction, the group said in releasing its annual Red List.
"The rate of biodiversity loss is increasing, and we need to act now to significantly reduce it and stave off this global extinction crisis," Julia Marton-Lefèvre, the group's director general, said in a statement.

The group noted that while extinctions are a part of nature, its findings show that humans are accelerating some extinctions. "Estimates vary greatly, but current extinction rates are at least 100-1,000 times higher than natural background rates," it said in a statement.
In what is billed as the world’s most authoritative assessment of Earth’s plants and animals, the group considered 41,415 species and found that of those, 16,306 were under threat, said Craig Hilton-Tailor, the list’s manager.

That is 188 more species than last year. Even so, Hilton-Tailor said, there are probably many more than that.
'Tip of the iceberg'“The estimate is low; we know it’s low,” he said. “We’ve only really looked at the tip of the iceberg in terms of species that are out there that are known to science.”
The total number of extinWhile it does not play a major role in U.S. decisions on wildlife conservation because the United States does this through its own Endangered Species Act, the IUCN is highly influential in other regions, particularly in developing countries that cannot afford to make their own assessments of which species are in trouble.
Its members includes nations, government agencies, non-governmental organizations and thousands of scientists.

The IUCN noted that while the total number of species on the planet is unknown, estimates vary between 10 million and 100 million — with 15 million species being the most widely accepted figure. Nearly 1.8 million species are known to exist.
Corals and warming seasFor the first time, corals were added to the list due to threats that include the warm-water Pacific Ocean pattern El Nino and global warming.
"The fact that corals are now present on the IUCN's Red List should sound warning bells to the world that the oceans are in trouble," said Simon Cripps, director of the global marine program at the World Wildlife Fund, an IUCN partner.

Hilton-Tailor said global warming is a factor in these and other species’ endangerment, but not the only factor.ct species has reached 785 and a further 65 are only found in captivity or in cultivation, the group, also known by the acronym IUCN, said in its statement.
One in four mammals, one in eight birds, one third of all amphibians and 70 percent of the world’s assessed plants on the 2007 Red List are in jeopardy, the IUCN added

“It’s really hard to identify whether it’s climate change or not that’s driving some of these species to extinction,” he said. “Climate change doesn’t operate by itself, it’s operating in tandem with other threats and it’s usually the combination of climate change and possibly the threat of a new disease ... it’s different combinations that can push species over the brink.”

The Galapagos Islands saw 10 native coral added to the list, as well as 74 seaweed species.
Besides being affected by warmer water, the seaweeds are also indirectly affected by overfishing, which removes predators from the food chain and results in an increase of sea urchins and otherEbola wiping out gorillasAsked to name a particularly troubling example of an endangered species, Hilton-Tailor mentioned the western lowland gorilla, which moves from endangered to critically endangered on the latest list. Its decline is due to the Ebola virus and commercial hunting of so-called bush meat.

"In the last 10 years, Ebola is the single largest killer of apes. Poaching is a close second," said Peter Walsh, a member of IUCN's primate specialist group. "Ebola is knocking down populations to a level where they won't bounce back. The rate of decline is dizzying. If it continues, we'll lose them in 10-12 years."

Female gorillas only start reproducing at the age of 9 or 10 and only have one baby about every five years. Walsh said even in ideal conditions, it would take the gorillas decades to bounce back.
Hilton-Tailor said the plight of gorillas points up the need for better viral controls, and for an alternative source of food for people in the gorilla’s range, from Angola to Congo to Gabon. herbivores that overgraze seaweed beds.

Development is the culprit in the decline of the Yangtze River dolphin, also known as the baiji, Hilton-Tailor said. It is critically endangered and possibly extinct, with perhaps one or two individual creatures remaining in China.
Changes in river flows due to dams, pollution, over-fishing and the use of electric shocks to fish in the Yangtze system are all factors in the cetacean’s disappearance. Heavy river traffic in fast-developing China is another cause.
“Any poor dolphin would really have to do amazing acrobatics to avoid being hit by one of those ships,” Hilton-Tailor said.

Birds in declineFor birds, the Red List shows 1,221 species are considered threatened with extinction, and 189 species are listed as critically endangered. The overall status of the world’s birds has deteriorated steadily since 1988, when they were first comprehensively assessed.
Birds did see the only success story on this year's list, however. The Mauritius echo parakeet, which was one of the world’s rarest parrots 15 years ago, went from critically endangered to endangered — the only species to see its status improve.
The IUCN tied the improvement to close monitoring of nesting sites and supplementary feeding combined with a captive breeding and release program.

But it also expressed frustration that only one species on the list showed improvement.
"This is really worrying in light of government commitments around the world, such as the 2010 target to slow down the rate of biodiversity loss," said Jean-Christophe Vié, deputy chief of the IUCN’s species program. "Clearly, this shows that much more needs to be done."
The IUCN said that humans "are the main reason for most species’ decline" given their impact on habitat, introducing invasive species, unsustainable harvesting, pollution and disease. "Climate change is increasingly recognized as a serious threat, which can magnify these dangers," it said.

The group also noted that:

Most threatened birds, mammals and amphibians are on the tropical continents — the regions whose forests are thought to hold most of Earth’s terrestrial and freshwater species.
Of the countries assessed, Australia, Brazil, China and Mexico hold "particularly large numbers of threatened species."
The vast majority of extinctions since 1500 AD have taken place on islands, but over the last 20 years extinctions on continents have become as common as island extinctions.
Jane Smart, head of the IUCN’s species Program, added that protecting wildlife is in the interest of humans. "Our lives are inextricably linked with biodiversity," she said, "and ultimately its protection is essential for our very survival."

The full Red List database is online at iucnredlist.org.

Monday, October 8, 2007

Stem cell team wins 2007 Nobel for medicine

STOCKHOLM (Reuters) - Stem cell researchers Mario Capecchi, Martin Evans and Oliver Smithies won the 2007 Nobel prize for medicine or physiology for their work on gene changes in mice using embryonic cells, Sweden's Karolinska Institute said on Monday.

The prestigious 10 million Swedish crown (755,000 pound) prize recognised the international team's work, saying the benefits to mankind would increase in many years to come.

Capecchi was born in Italy and is a U.S. citizen. Both Evans and Smithies are British-born. Evans is a Briton while Smithies is a U.S. citizen.

The prize awarders said the discoveries made by the three have led to a new branch of medicine known as gene targeting.

This enables certain genes to be turned off "allowing scientists to establish the roles of individual genes in health and disease".

Almost every aspect of mammal physiology can be studied by gene targeting, the institute said.
Capecchi's research uncovered the role of the genes involved in organ development in mammals and has shed light on the causes of several human birth abnormalities.

Evans's work has helped in studying cystic fibrosis and in testing the effects of gene therapy. Smithies also worked on gene targeting for cystic fibrosis and the blood disease thalassemia as well as hypertension and atherosclerosis.

"In summary, gene targeting in mice has pervaded all fields of biomedicine," Karolinska said in a statement.

"Its impact on the understanding of gene function and its benefits to mankind will continue to increase over many years to come."

Medicine is traditionally the first of the Nobels awarded each year. The prizes for achievement in science, literature and peace bearing the name of Alfred Nobel were first awarded in 1901 according to the will of the Swedish dynamite millionaire.

Friday, October 5, 2007

Catching Fish Evolving

2 August 2004 article taken from

http://hcgs.unh.edu/News/ScienceNOW.pdf on 6 oct 2007


The myriad of colorful cichlid fishes of the African Great Lakes is a classic example of
explosive evolution, with thousands of species having appeared in the geological
equivalent of a blink of an eye.

Now, in a paper in this month's issue of, biologists report a close-up look at one spark in that burst of evolution. Molecular Ecology Lake Malawi, shared by Malawi, Mozambique, and Tanzania, is home to at least 500 species of cichlids, all of which probably took less than a million years to evolve from a common ancestor. Still, evolutionary biologist J. Todd Streelman of
the University of New Hampshire, Durham, and his colleagues were not prepared for the speed of evolution they discovered at the lake's Thumbi West Island.

Here, at a 100-meter-long promontory called Mitande Point, a fish dealer in the 1960s
released , a species restricted to the other end of Lake Malawi. Twenty years later, the fish hadn't ventured beyond Mitande Point. But in 2001, when the team dipped nets into the water at six spots along the island's 5-km-long coastline, the scientists found that it had spread everywhere. At each station, they netted some 40 individuals and recorded the color pattern for each.

They also took a so-called microsatellite DNA fingerprint. Cynotilapia afra As it turned out, had evolved into two distinct varieties in less than 20 years. The ones along the northern coast of the island had developed about four vertical blue bars on the black dorsal fin, whereas the ones along the southern coast had only two or C. afra has split in two in just 20 years. Amazing powers of evolution.

(The original stock had no blue bars on the dorsal fin.) Also, DNA fingerprints of fish from the north coast sites were significantly different from those of fish in the south, making it likely that the two are well on their way toward becoming separate species. Fish evolution this hasty has been recorded so far only in salmon and sticklebacks. "We were not expecting [this]," Streelman says.

Evolutionary ecologist Jacques van Alphen of Leiden University in the Netherlands is
amazed at the speed with which has split in two. "It's a very nice finding," he
says. But he hopes the researchers will continue their work to find out what is different
about the two sides of the island to have caused the two forms to evolve.

--MENNO SCHILTHUIZEN

Thursday, October 4, 2007

WANTED GREENER FISH

Wanted: greener fish

This news coming from the FAO chief are a welcome development, look at efforts the market is doing in order to save the remaining fishery resources.

The FAO State of Fisheries and Aquaculture Report 2006, clearly said that capture stocks have reached their ceiling and aqua production is increasing.

However it does not require a rocket scientist to understand that the aqua stocks will require capture bycatches as their feed stock ingredients, yes the much required 60 % protein source.

SO WHERE DO WE GO FROM HERE?

Ecosystem management approach .

Hastings

=======



Market trends require stronger environmental performance by seafood industry
25 September 2007, Rome - The US$400 billion seafood industry has no choice but to adapt to intensifying demand from retailers and consumers for "environmentally friendly" fish, FAO said today.During opening remarks made to industry representatives attending the 2007 Seafood Industry Congress (25-27 September, Dublin), Grimur Valdimarsson, Director of FAO's Fishing Industries Division, said that the need for seafood producers to guarantee environmental performance is unavoidable."

The push towards sustainable fisheries is not just coming from government or environmental groups, but from the market itself," Valdimarsson said, noting that major seafood retailers like Unilever, Tesco, Walmart and Asda have already committed to putting on their shelves only fish that was harvested or raised sustainably."

In recent years the seafood industry has been uncertain as to whether these trends represent a momentary fad. Today, there's no question: it's real, it's a sea change, and it's the way of the future," he said.In broad terms, this means that producers will need to be able to assure retailers and consumers that their fish were not taken from overexploited stocks, farmed in ponds where mangroves once stood, or caught in nets without turtle-saving excluder devices installed.

Doing so requires monitoring fishing activities via tracking systems, labels and similar mechanisms. There are already a number of initiatives under way that seek to do this, established either by seafood retailers or public interest organizations.

While expressing concern over the proliferation of diverse and competing efforts, Valdimarsson stressed that, overall, the trend is a positive one.Transition anything but easy"Complying with these new imperatives is technically extremely difficult, and so the challenge facing industry right now is finding ways of doing so that are both adequate and economically feasible," Valdimarsson acknowledged.

The capture fisheries sector should draw lessons from the last 25 years of food safety assurance in other sectors, which moved largely from being a government-run activity to one managed by industry itself within a government-established framework and subject to spot verification.Seafood producers have been wresting with a similar problem for years now, which could help."

Already, producers have put into place internal systems to ensure that they are providing seafood that is fresh, safe to eat, and of the highest quality -- which is what today's consumers demand," Valdimarsson said. "You don't need to invent a new agency to guarantee that environmental standards are being met -- monitor for environmental performance in a similar way, as you do for safety and quality."

Developing countries will have a tough timeResource-strapped developing countries will have a particularly hard time making the transition to fully certifying their fisheries."They've already been struggling mightily to comply with health and safety regulations on fish imports put into place by importing countries in the developed world," Valdimarsson explained.

Helping resolve this problem is an issue of particular importance to FAO, he said, adding that the retailers shaping market trends have a responsibility to help suppliers in the developing world cope.And FAO and other international development organizations working on fisheries and aquaculture will need new resources to help the developing world's fisheries sector adapt.Fishing rights keyThe widespread practice of granting open or nearly-open access to fishing grounds is another challenge."

Under the open access regime, fishing is an extremely competitive, zero sum game: if a fishermen doesn't land a fish, his competitor will, leaving little incentive to conserve the resource" according to Valdimarsson, and the consequence is overfishing. "So fishermen have a vested interest in not revealing what they've been doing.""T

hat must change, because the emerging paradigm requires the industry to be able to say exactly where, when and how a fish was caught. Only fishermen who hold clear rights and are not obliged to outfish a large group of competitors will feel secure enough to operate with that level of transparency."

Safety and quality issuesThis year's World Seafood Congress was co-organized by FAO, the United Nations Industrial Development Organization, the World Health Organization, the International Food Quality Certification Group, and Ireland's Sea Fisheries Protection Authority in collaboration with the International Association of Fish Inspectors and with the support of the Irish Sea Fisheries Board, Enterprise Ireland, and the Food Safety Authority of Ireland.

The congress has traditionally focused on seafood safety and quality issues, but environmental concerns have risen higher on its agenda in recent years.One of the most serious difficulties faced by fish exporters is coping with different safety standards being imposed by various importing countries. The need for greater harmonization of standards and more equivalence agreements, as well as the proliferation of private standards and certification schemes for fish products will also be discussed in Dublin.

Contact:George KourousMedia Relations,
FAO george.kourous@fao.org
(+39) 06 570 53168(+39) 348 141 6802

Monday, October 1, 2007

Women divers better than men – it’s official



Do we have any regulatons on divers and lake malawi bodiversity protection. Yes we do not have coral reefs to destroy, BUT what about the bowers or nest of cichlids in the sandy shores habitants? AND do I hear ou well, OR someone is saying what about the slimy algae on the rocky habitants YES that food for the colourful mbuna??


HASTINGS UNDER WATER L. MALAWI
Makes me think some policy issue here between all stake holders, Fisheries Dept and Parks Dept, YES include tourism DEPT as well.


Should we say only women should be diving in Lake Malawi??


hastings

==============


SOURCE: University of Hull website


Yes your are right thats me underwater Lake Malawi




Increased diving activity means that environmental damage is becoming more of a problem, but research done by the Scarborough Campus at the University of Hull suggests that men are more to blame than women Recreational scuba-diving is increasing in popularity, with holidays to exotic locations providing the perfect opportunity to explore life underwater.


The experience can be enjoyed for as little as £200, bringing money into areas where it is badly needed. The down side is that divers cause damage to reefs by accidentally breaking off bits of coral when they are swimming over it – ironic when the very thing that attracts divers to the reef is their beauty and the fish that congregate around them.


Diver damage occurs due to a lack of buoyancy control, which causes sediment disturbance, covering the reef and suffocating it. But how do divers achieve good buoyancy control?


According to Mandy Shackleton, a Masters student from the University’s Centre for Environmental and Marine Sciences, relaxation and a good breathing technique are key to maintaining control and minimising damage. Mandy has spent the last three years in Kenya, where she observed 500 divers and measured their impacts on coral reefs.


Mandy, a qualified dive master, created an underwater tick sheet to assess the different types of damage caused by male and female divers. Mandy says, “When men go diving, they experience ‘sensation seeking’.


This triggers a chain reaction of hormones: the first to be released is the stress hormone cortisol, then testosterone – the hormone linked with aggression – and finally, adrenalin. The combination of these three results in erratic, dangerous diving. By contrast, female divers have better orientation underwater: they have a greater awareness of what is going on around them, they are more conscious of safety and therefore dive with greater care.”


Dr Magnus Johnson, Head of the Centre of Environmental and Marine Sciences says, “Mandy’s research is particularly interesting because above water, men are usually cited as having better spatial awareness than women. It is perhaps a good job that men don’t have to parallel park or change lanes underwater. They would lose their no clams bonus!”

Saturday, September 29, 2007

Malawi awarded on climate change

This story can not go without comments from people who are so concerned with the strategies we are putting in place as Malawians on climate change. The recognition by the world body on steps taken by our counry on climate change just shows how committed as Malawians both government and individuals we are to fight this war on climate change.

It is not true to say tha Malawi does not cotribute to green house gases, but its only affected by the developed countries. As log as we are building dual carriage Masauko Chipembere Highways, then we are in the same wagon of producing green house gas by our cars traveling on those roads, let alone the high taste of 4 X 4 s by our cooporate and elite society.

I recommend the government for tracking the disposed of HCFCs refrigerators and giving a figure of remaining 15 % to deal with the problem. This just shows we are in control.

Read on the good news..

Hastings
==========

Read the story as reported BY CHARLES MPAKA 11:39:06 on 29 September 2007.

The Montreal Protocol, an international treaty designed to protect the ozone layer by phasing out of ozone depleting substances, has awarded Malawi for its strides in controlling the concentration of the gases in the country. Minister of Lands and Natural Resources Khumbo Chirwa announced this Thursday in an interview.Chirwa, who had just returned from a conference on climate change in Montreal, Canada, said the meeting recognised Malawi, alongside Nigeria and Mauritius, for its efforts in reducing levels of hydrochlorofluorocarbons (HCFCs), methyl bromide and other substances.

HCFCs, which are used in refrigerators and air conditioners, are said to be 10,000 times more potent to greenhouse effect than carbon dioxide, and therefore contribute immensely to global warming. According to Chirwa, Malawi Revenue Authority (MRA) has played a part in checking levels of the substance in the country through inspection of refrigerators and related equipment being smuggled into the country.

The minister said Malawi had so far reduced about 85 percent of the levels of the substances. The Montreal Protocol previously suggested complete phase out of HCFCs by 2030 but according to Chirwa, the deadline was not realistic considering large volumes of the substances being used in industrialised countries. “On our part, we still have to fight off the remaining 15 percent.

We are getting there but we need to accelerate our efforts. Various stakeholders have worked together for this achievement but we need to involve communities more,” Chirwa said. In 2006, Malawi developed the National Adaptation Programme of Action (Napa), a plan intended to identify priority activities that respond to her urgent and immediate needs with regard to adaptation to climate change.

The plan highlights the need to involve rural communities in vulnerable areas of the country. Sam Kamoto, Programme Manager for Wildlife and Environmental Society of Malawi (Wesm) said Malawi was being heavily impacted upon by greenhouse gases from industrialised countries, despite itself not contributing towards global warming.

The environmentalist said a coordinated and enhanced participation of local communities and civil society would help a great deal in tackling issues of climate change. Malawi was the first country in the world to phase out methyl bromide, another ozone depleting substance, in 2004.

The Montreal Protocol had recommended the phase out of the substance in developing countries by 2015. Malawi was then the second largest user of the chemical after Zimbabwe because of the tobacco industry, a major forex earner for both countries.

Wednesday, September 26, 2007

Crocs Found to Swim Up to 24 Miles Daily

ANDREA THOMPSON

FROM: LIVE SCINCE DOT COM

Known for their lethargy, crocodiles weren't suspected to be top long-distance travelers, but a new study shows that they can cover up to 24 miles a day and find their way home from enormous distances.

To test crocodile swimming skills, researchers relocated three crocs between 32 and 80 miles (52 and 130 kilometers) away from their homes just north of Queensland, a state in the northwest of Australia, and set them free to see how well they could find their way back.


The study technique was largely put into practice by the efforts of the late Steve Irwin. Specially-designed transmitters attached to the back of the reptiles' heads allowed scientists to monitor progress, with some astounding results: the crocs swam between 6 and 24 (10 and 39 kilometers) a day, much farther than scientists previously thought they could.


One crocodile even swam around the northern tip of the Cape York Peninsula (which juts northward out from Queensland toward Papua New Guinea) to reach home, covering more than about 250 miles (400 kilometers) in 20 days.


"We often thought crocodiles tired very quickly, but here we show very clearly that they are capable of moving long distances for days on end," said study leader Craig Franklin of the University of Queensland.


Franklin says that the crocs, like birds, probably use many factors to navigate, including the position of the sun, magnetic fields, sight and smell.


"Crocodiles are more closely related to birds than they are any other reptile, so they are possibly using navigation systems similar to birds," Franklin said.


The data from the satellite tracking study, detailed in the online journal PLoS ONE, show that estuarine crocodiles are capable of moving phenomenal distances over prolonged periods of time in the ocean.

Thursday, September 6, 2007

Study: Wrong fish used to save species

By JUDITH KOHLER, Associated Press Writer Wed Sep 5, 9:12 PM ET

DENVER - A 20-year government effort to restore the population of an endangered native trout in Colorado has made little progress because biologists have been stocking some of the waterways with the wrong fish, a new study says.

Advances in genetic testing helped biologist discover the error, which was called a potential black eye, but they said there is still hope for restoring the greenback cutthroat trout.
The three-year study, led by University of Colorado researchers and published online in Molecular Ecology on Aug. 28, said that five of the nine populations believed to be descendants of the endangered trout were actually the more common Colorado River cutthroat trout, which look similar.

The study said the results imply that the effort has "failed to improve the species' status."
Lead author, Jessica Metcalf, who recently completed her doctorate in ecology and evolutionary biology at the university, was optimistic about the ongoing restoration program because four populations have been identified as "pure greenback cutthroat trout."
Bruce Rosenlund of the U.S. Fish and Wildlife Service, which is leading the recovery effort, said the agency is reviewing the study.

"The report is just a continuation of different expert input provided to the team for consideration for restoration," Rosenlund said.

Colorado and federal biologists have a goal of 20 self-sustaining populations of at least 500 fish each. The cost of the program was not available.

Greenback cutthroat trout were historically found in the drainages of the Arkansas and South Platte rivers in Colorado and a small part of Wyoming. They were declared extinct in 1937 because of overfishing, pollution from mines and competition from nonnative fish.

Researchers said remnant populations were found in the 1950s in tributaries and provided brood stock for fish raised in federal and state hatcheries and released in their native habitat.
The fish was added to the federal endangered species list in 1978.

The greenback were believed to be in 142 miles of waterways, including in Rocky Mountain National Park, Rosenlund said.
The new study, based DNA test results, found the greenback cutthroat trout's range is only 11 miles of streams.
The research results are a setback but state biologists believe the program will succeed over the long term, said Tyler Baskfield, Colorado Division of Wildlife spokesman.
"We've been moving fish around in the state since the late 1800s, and now the new science comes in and all of a sudden it's a different playing field," Baskfield said.
University of Colorado professor Andrew Martin, the study's principal investigator, said that while the findings might give the recovery program a "black eye," the hope is that biologists and agencies will move ahead on recovering the species before it goes extinct

Wednesday, July 11, 2007

Sun is not to blame for global warming

My interest has always been on the impact of global warming on Zambezi and rovuma catchment areas. What will global warming contribute towards the water levels and fauna of these catchment.

These catchment are amongts the concetrated with worlds diversity, and one school of thought is that the evolution of fishes in these catchment has been contributed by the different water levels several thousand s of years being low and high at some point. This has led to emergence and divergence of fish species, presently ranking high among the colour polymorphism and hence preference from the aquarium traders.

How Will the impending excess or scartity of water affect the species diversity of this african rift valley??? ........

Hastings Zidana
=====================

AFP - Wednesday, July 11 10:25 am
PARIS (AFP) - Scientists on Wednesday said that the rise in global temperatures that has been detected over the past two decades cannot be blamed on the Sun, a theory espoused by climate-change sceptics.

British and Swiss researchers looked at data for radiation from the Sun, levels of which can cool or warm our planet's atmosphere.

They factored in a cycle which solar radiation goes through peaks and troughs of activity over a period of about 11 years.

Writing in Proceedings of the Royal Society A, a journal of Britain's de-facto academy of sciences, the team said that the Sun had been less active since 1985, even though global temperatures have continued to rise.

"Over the past 20 years, all the trends in the Sun that could have had an influence on the Earth's climate have been in the opposite direction to that required to explain the observed rise in global mean temperatures," they write.

The study is co-authored by Mike Lockwood of Britain's Rutherford Appleton Laboratory and Claus Froehlich of the World Radiation Centre in Switzerland.

The overwhelming consensus among scientists is that human activity is to blame for the rise in global temperatures. In its latest report, issued this year, the UN's Intergovernmental Panel on Climate Change (IPCC) said that this warming is already affecting the climate system.

Since 1900, the mean global atmospheric temperature has risen by 0.8 C (1.44 F), and the sea level by 10-20 centimetres (four to eight inches).

Levels of carbon dioxide (CO2), the main greenhouse gas, have risen by around a third since the Industrial Revolution and are now at their highest in 650,000 years. Eleven of the past 12 years rank among the dozen warmest years on record.

In the past few years, glaciers and snow and ice cover have fallen back sharply in alpine regions, the edges of the Greenland icesheet and on the Antarctic peninsula have shrunk, Arctic summer sea ice has thinned and retreated and Siberian and Canadian permafrost have shown signs of thaw and fallback.

Saturday, May 12, 2007

GLOBAL WARMING IS REAL


Fellow Biodiversity lovers


As we can see from the artcle below it clearly shows THAT GLOBAL WARIMNG IS REAL.

my questin has been and is always "What is our role as Malawians ?" Do the parliamentarians take this issue with a priority?.
The image clearly shows that Malawi is in the band of "Areas at most risk". Let us act now by putting in place necessary policy issues like-irrigation for all crop fields by the year 2030 or 2040, thats 10 yeras before the real thing is on our neck. We can do it there are several organisation dealing with global warimng and environment where, we can tap the resources let alone the credit income which they have just been written off by our creditors. As a country we can put that money to good use other than politicking by suggesting mitigation moves of glaobal warming.
Do not say I did not warn you, have a good reading below.
Hastings
=================

Drying up and flooding out
May 10th 2007 NAIROBI From The Economist print editionRich countries may be largely to blame for adding climate change to Africa's litany of problems, but the continent's own politicians have yet to take it seriously
AT A recent African Union summit, Uganda's combustible president, Yoweri Museveni, declared climate change an act of aggression by the rich world against the poor one—and demanded compensation. The moral arguments on climate change are even murkier than arguments about other wrongs done to Africa, such as slavery, but Mr Museveni may have hit on something. If the predictions of the UN's Intergovernmental Panel on Climate Change (IPCC), hold true, climate change may have a graver effect on Africa than on any other continent; the final part of the panel's latest report has just been published (see article). Scientists now blame industrialisation (read, the rich world) for some of the warming. In any event, the contrast between poverty in Africa and carbon gluttony elsewhere is sharp. Why should the poorest die for the continued excesses of the richest?
The IPCC's most recent regional report certainly raises the spectre of rising mortality. It predicts a minimum 2.5°C increase in temperature in Africa by 2030; drylands bordering the deserts may get drier, wetlands bordering the rainforests may get wetter (see map). The panel suggests the supply of food in Africa will be “severely compromised” by climate change, with crop yields in danger of collapsing in some countries.
In the drylands, water may become a critical issue. Soaring temperatures and erratic rainfall may dry up surface water. Between 75m and 250m Africans, out of the 800m or so now living in sub-Saharan Africa, may be short of water. The soil will hold less moisture, bore-holes will become contaminated, and women and girls will have to walk ever greater distances to fetch water. Vegetative cover will recede. The IPCC guesses that 600,000 square kilometres (232,000 square miles) of cultivable land may be ruined.
Warming may also hurt animal habitats and biodiversity. More algae in freshwater lakes will hit fishing. The glaciers of Uganda's Rwenzori mountains, of Tanzania's Kilimanjaro and of Kenya's eponymous mountain may disappear; only seven of the 18 glaciers recorded on Mount Kenya in 1900 still remain. At the same time, a likely rise in sea levels may threaten the coastal infrastructure of northern Egypt, the Gambia, the Gulf of Guinea and Senegal.
There are two caveats to this gloomy scenario. The first is that some parts of Africa may benefit from climate change. Increased rainfall in highland areas in eastern Africa could, for example, be beneficial. Second, though climate-change models have improved, they have been unreliable in Africa. The broad outline is plain but the detail is guesswork.
Still, some scientists think that climate change may be even crueller to parts of Africa than the IPCC predicts. The important point, they say, is not the degree of warming but the continent's vulnerability to it. A University of Pretoria study estimates that Africa might lose $25 billion in crop failure due to rising temperatures and another $4 billion from less rain. The already impoverished drylands would suffer most. Some cite the war in Sudan's Darfur region as proof of the damage done by climate change, soil erosion and overpopulation.
Unfortunately, few African leaders have grasped the scale of the challenge posed by climate change. Most oil-producers have squandered their bonanza. Nigeria has failed to plan for how to stem the dreadful pollution in its oil-producing Delta region or to prevent desertification tearing at the fabric of its dry Muslim north. South Africa is only just beginning to own up to its coal addiction. Uganda's Mr Museveni is fighting off a rare insurrection from his supporters against plans to turn a piece of Ugandan rainforest over to farming. The World Meteorological Organisation says that weather-data collection in Africa has recently got worse, just as the need for accurate figures has grown; many of the automatic weather stations it helped set up have fallen into disrepair. The African Union has done little to sound the climate-change alarm.
Kenya's president, Mwai Kibaki, says that Africa should “join hands” with its friends in the rich world over climate change. He wants more carbon-trading projects to come to Africa; so far, most have gone to Asia. His advisers admit that Mr Kibaki's ambitious plan to turn Kenya into an industrial country by 2020 worries environmentalists, but say that reforestation, thermal power and better management of water and grazing would, if they materialised, offset the damage.
Africa emits far less carbon than other continents, so its recently faster-growing economies do not gravely menace its environment. Some rich-country consumers, however, want to punish African countries for airfreighting northwards some of their produce, from flowers to wine.
Hardier new varieties of staple crops, drip irrigation schemes and technologies such as solar power should help Africa adapt to climate change. But so can simple shifts in policy. For instance, a government decision in Burkina Faso to let farmers own the trees on their land has increased the country's tree cover.
Most vital of all is the cash—probably from rich countries—to pay for roads, schools, clinics and improvements in livestock management in the most vulnerable regions. Whether Mr Museveni's outrage will sway donors is unclear. As the G8 rich countries are failing so far to fulfil the promises they made in 2005 to boost aid to Africa, the continent should not expect much new money to protect the environment. In the short run, Africa's own politicians need to take a lead, even if the people most culpable for the damage done by climate change live elsewhere.

Friday, March 30, 2007

FISH INTRODUCTIONS WITHIN LAKE MALAWI

The introduction of exotic fish species to areas where they do not naturally belong is a global problem. Apart from cases of exotic species, there are also many more cases of species transplant within the same watershed, this is the issue which mainly affects most of African and indeed Malawian water ecosystems.

What is of great concern to ecologists, enviromentalists, biologists and genetists alike is what happens next after an introduction has occurred. Mainly a concern is whether a fish species which has been introduced to a new ecosystem is going to establish itself in that new environment.

The law of nature dictates "survival of the fittest", this is equally true with the new introduced fish species to any ecosystem, whether it is a lake, river, reservoir or pond. The new species needs to have an added advantage over the native species in order to do well in the new habitant. If the ecosystem is already diverse enough and strong the new species has problems to deal with its survival. In most areas in the wolrd, aquatic ecosystems have been tampered enough so that their structures are no longer strong to resist the establishment of new species in their territories. This has been due to high human population in most shorelines, which have impacted these ecosystems to the extent of affecting their assemblages.

Lake Malawi is one of those ecosystems which has suffered human impacts due to increasing settlements and farming activities near or in the shore line. This has affected the breeding grounds of many fish species including, the most totted Lake Malawi Tilapia commonly known as 'Chambo". As if this is not enough, the Lake Malawi ecosystem is also at the moment suffering from fish transfers or what ecologists call it fish translocations. This is happening mostly with the most colourful species which are commonly known as "Mbuna". The high demand of the Malawian Mbuna to European and Asian markets has led fishermen to capture these tiny spcies as far as the northern waters and send them to the southern waters where they are freighted to outside markets. It is during these processes that some of the Mbuna species are dropped on the way and hence found to be where they do not belong.

At the moment it is not yet known whether these small species will be able to establish themselves in the new ecosystems. But the questions which we should aks ourselves as Malawians are: why do we have so many fish species coexisting in lake malawi? what mechanisms are these species using to coexists? why different fish colours in different geographic areas within the lake? what will be the response of the native species?

As one way of trying to answer these questions, I have put forward a proposal which is being funded by British Council. Anyone willing to help or collaborate in this venture just contact me using my email.

Monday, January 8, 2007

Fish behaviour and light

LIGHT AND BAHAVIOUR
Light, both direct and indirect, is of great importance in the lives of fishes. In the majority of fishes, the visual organs play a substantial role in orientation during swimming, towards prey, predators, other individuals of the same species in a school, or immobile objects.

The behaviour of fish, particularly their diurnal activity and many other aspects of their life, are significantlyrelated to the degree of illumination (Kikolsky 1963). Light exerts a definite influence on a fish's metabolism, maturation, behaviour and colouration.

LIGHT WAVELENGTHS AND FISH COLOURATION
Light conditions in water differ from those on land not only in their intensity but also in the depth of penetration of the various wavelengths. The longer wavelengths (i.e. red, orange) are absorbed first, with over 25% of red light being absorbed in the first metreof water. Violet, on the other hand, becomes indistinguishable below a depth of 100 m or more (Nikolsky 1963).

Since a high percentage of red light is filtered out in the first few metres of water, bright red fishes are common. Fishes that are solid red in colour aregenerally either nocturnal or live at moderate depths (Chech andMoyle 1982).

In both situations, red light is virtually absent and ared fish tends to fade into the background rather easily. However,many shallow water fish also have red spots or lines. It is thought that such colouration is important in recognition and/or breeding; red colours would be highly visible over short distances but is difficult to see over large lateral distances (water absorbs the red)(Chech and Moyle 1982).

The visual spectrum of fish depends on the nature of their habitat; fish which live in predominantly shallow waters are more sensitive to the longer wavelengths of light (red) while, as depth increases, the visual spectrum narrows considerably, starting with the longer wavelengths (Nikolsky 1963). The majority of fish can distinguish colours quite well although the maximum distance they can see is apparently not greater than 15 metres (Nikolsky 1963).

FISH ADAPTATION TO LIGHT
Fish have a number of adaptations to varying light levels. The rodsin the retina of the eye are specially adapted for sensing in weaklight. During periods of bright illumination (i.e. daylight), the rods become buried in between pigment cells lining the retina. In contrast, the cones which are adapted to sensing brighter light, move to the surface in response to higher illumination (Nikolsky 1963). The lower part of the retina, in the majority of fish, possesses more cones, and fewer rods, than the upper surface. This is due to the fact that the upper part of the eye receives more dispersed light than thelower half of the eye (Nikolsky 1963).

A rather obvious adaptation to low light levels in a relative increase in the size of eye. This affords a much greater area for light detection. A fish with large eyes is always a give away that it should be kept in a tank with either low light levels or caves and overhangs (i.e. Squirrel fish[Holocentridae] and Cardinal Fish [Apogonidae]).

LIGHT EFFECTS ON FISH BREEDING
Light also has profound effects upon the internal mechanisms of fish. For example, light exerts a great influence on the maturationof fish as well as their development and metabolism. For a number of fishes an increase in the amount of illumination produces asignificant acceleration in the development of the egg. This often takes the form of an increase in development rate in the light and a decrease in the rate in the dark (Nikolsky 1963).

In many fish species, the maturation of the gonads depends to a large extent on the duration of light (the so called photoperiod) and its intensity. In tropical seas, where the photoperiod is not as variable as in temperate areas, the role of light is not as important and many tropical species breed year round (Nikolsky 1963).

If fish do not receive the correct amount and intensity of light, they can be severely crippled and may not develop properly. In many fish species the normal course of metabolism is disturbed if they are reared in light conditions which are abnormal for them (Nikolsky 1963).

LIGHT EFFECTS ON PREDATION
The activity patterns of most fish are also related to light.Vision-orientated predators are most active during the day, oftenwith peaks of feeding in the early morning and evening when invertebrates become more available. Piscivorous fishes are alsomost active at dawn and dusk; attracted by the feeding activities ofthe smaller fish which form their prey. At night, the day-activefish become quiescent and the nocturnal fish become active (Chech andMoyle 1982).

In this article I have pointed out some of the basic reactions of fish to light; both its duration and intensity. It can be seen that light plays a very important role in the lives of fish and this must be taken into account when keeping them in enclosed systems.

Thursday, January 4, 2007

Ethanol-driven vehicle under test in Malawi

conducting road tests on an ethanol-propelled vehicle.
Supporters of the project argue that a switch to ethanol fuel would not only benefit the environment but also increase employment in the country's sugarcane industry and save on foreign exchange spent on fuel imports.
According to Freeman Kalirani, a lead researcher on the project • based at Lilongwe Technical College and conducted jointly with the department of science and technology • a modified Mitsubishi Pajero will be tested over a 350 kilometre route from Lilongwe to Mzuzu.
The five-year, US$1 million project, backed by the Malawi government, is investigating the practicability of flex-fuel vehicles that use either 100 per cent locally manufactured ethanol, or a combination of ethanol and petrol.
Until February 2006, all cars in Malawi used leaded petrol blended with 20 per cent ethanol. Since then, the country has switched to unleaded petrol blended with 10 per cent ethanol. Proponents of ethanol use argue that continued over-dependence on fossil fuels has economic, social, climate and biodiversity impacts for humans and the entire ecosystem.Kendron Chisale, Malawi's deputy director of science and technology, said a switch to ethanol would allow Malawi to comply with procedures aimed at emission reduction, as agreed by parties at the 2006 United Nations Climate Change Conference in Nairobi in November. "This will eventually mitigate climate change related disasters," he says.
Charles Mtonga, an economic analyst, told SciDev.Net that one advantage of using ethanol as a renewable energy source is that it can increase employment in the sugarcane industry. "It can also save on foreign exchange lost through importation of petroleum products," he said.
But Mtonga cautioned against over-enthusiasm, calling for continued research on how vehicles previously propelled by petrol can best be modified to use ethanol.
He also warned that huge investments in production and installation of additional pumps would be required to make ethanol fuel available throughout the country.Malawi produces ethanol from sugar molasses in bulk amounts at Dwangwa, in the central region lakeshore district of Nkhota-kota.
6 times read

2007 set to be world's warmest year - Met Office

LONDON (Reuters) - This year is set to be the hottest on record worldwide due to global warming and the El Nino weather phenomenon, the Meteorological Office said on Thursday.
The Met Office said the combination of factors would likely push average temperatures this year above the record set in 1998. 2006 is set to be the sixth warmest on record globally.

This new information represents another warning that climate change is happening around the world," said Met Office scientist Katie Hopkins. The world's 10 warmest years have all occurred since 1994 in a temperature record dating back a century and a half, according to the United Nations' weather agency.

The Met Office makes a global forecast every January with the University of East Anglia, and said it expected the world's average temperature to be 0.54 degrees Celsius above the 1961-1990 long-term average of 14.0 degrees.

There is a 60 percent probability that 2007 will be as warm or warmer than the current warmest year, 1998, which itself was 0.52 degrees above the long-term average it said in a statement.

Most scientists agree that temperatures will rise by between two and six degrees Celsius this century due mainly to carbon emissions from burning fossil fuels for power and transport.

They say this will cause melting at the polar ice caps, sea levels to rise and weather patterns to change bringing floods, famines and violent storms, putting millions of lives at risk.

Former World Bank chief economist Nicholas Stern said in October that urgent action on global warming was vital and that delay would multiply the cost by up to 20 times.

The Kyoto Protocol is the only global action plan to curb carbon emissions, but it expires in 2012, is rejected by the world's biggest polluter -- the United States -- and does not bind booming economies like China and India.

The Met Office said the established moderate El Nino, a phenomenon in the tropical Pacific blamed for disrupting weather patterns, would continue for the first few months of 2007.

It noted that as there was a time lag between El Nino and its full effect on surface temperatures, its influence would therefore be felt well into the year.

It will coincide with what environmentalists say will be a very busy year for climate diplomacy.

Germany, which has an active climate change agenda, has taken over the six-month rotating presidency of the European Union and the year-long presidency of the Group of Eight industrialised nations.

Backed by Britain, which has pushed climate change high up the world agenda, pressure is building for the G8 summit in Germany in early June to set out a framework for discussions to take global action beyond Kyoto

Tuesday, January 2, 2007

LAKE MALAWI MBUNA


Mbuna is the common name for a large group of African cichlids from Lake Malawi. The name mbuna is translated as rock fish. As the name implies, mbuna are the cichilds that live among piles of rocks, as opposed to living in the open water like many other haplochromines.
These cichilds are some of the most colorful freshwater fish for the home aquarium. Mbuna, pronounced with only one syllable, are very aggressive and territorial fish, although they are suitable for beginner fishkeepers who have researched their needs. A suitable aquarium setting includes many rocks, caves and hiding places; plants may be uprooted so they are best avoided but a small number will work well in the aquarium. These include Java fern, which may become the object of mbuna aggression but will not be eaten due to an undesireable taste.
Sand or gravel is the ideal substrate. The hobbyist will want to mix in some sort of so-called "live rock" as a pH buffer. However, crushed coral and specially mixed bags of substrate will do. Generally, tanks of no less than 55 gallons are required for mature Mbuna; 29 gallon tanks will work beautifully for juvenile fish but will need to be upgraded as they mature, grow and become more aggressive and territorial (this will occur in just a matter of weeks or months).

These cichlids are usually kept in well filtered, heavily stocked mbuna-specific aquariums. Over-crowding helps spread out the aggression and no particular individual gets picked on to death. They are maternal mouthbrooders and breed readily in good conditions. Mbuna are mostly herbivorous and their diet should consist of low fat foods. Many species will require spirulina, but worms, beefheart, and meaty foods are best avoided.

There is a wide array of literature out there concerning African cichlids (including references to mbuna in more general aquarium guides and scientific texts). There are subtle but important differences from book to book (and especially from internet site to site). Differences include whether or not to attempt an under-gravel filter and specific species compatibility. Make sure that you double check any recommendations with a second or third shopkeeper, experienced aquarist or printed text. The time and monetary investment required for a 75 gallon or larger aquarium demands it.
Many mbuna cichlids are regularly stocked and sold by pet shops. Some of the most common ones are bumblebee cichlid, auratus cichlid, electric yellow cichlid, red zebra cichlid, and johanni cichlid. Cichilds belonging to any of the genera listed below is usually considered mbuna.

An electric yellow cichlid, Labidochromis caeruleus.

Labeotropheus fuelleborni
Cyathochromis Trewavas 1935
Cynotilapia Regan 1922
Genyochromis Trewavas 1935
Gephyrochromis Boulenger 1901
Iodotropheus Oliver & Loiselle 1972
Labeotropheus Ahl 1926
Labidochromis Trewavas 1935
Maylandia Meyer & Foerster 1984.
Melanochromis Trewavas, 1935
Petrotilapia Trewavas 1935
Pseudotropheus Regan 1922

The list below includes groups of non-mbuna mouthbrooding cichilds from Lake Malawi.
Peacock cichilds
Haplochromines

LAKE MALAWI FACT FILE

Coordinates
10°00′S 34°00′E

Lake type
Rift Valley lakes

Primary sources
Ruhuhu

Primary outflows
Shire River

Basin countries

Mozambique Malawi Tanzania

Max-length
560 km

Max-width
75 km

Surface area
29,600 km²

Average depth
292m

Max-depth
706m

Water volume
8,400 km³

Surface elevation
500 m

Islands
LikomaChizumulu

Settlements
Niassa, MozambiqueRuvuma, Tanzania

LAKE MALAWI WILDLIFE

Lake Malawi has traditionally provided a major food source to the residents of Malawi as it is rich in fish, the most famous of which are the chambo, consisting of anyone of 4 species of the cichlid genus Nyasalapia, as well as the kampango, a large catfish (Bagrus meridionalis). Lake Malawi is famous for its cichlids, popular in the aquarium trade. Malawi cichlids are divided into two basic groups. These are loosely referred to as the haplochromines and the tilapiines. Within this first group (Haplochrominae) there are two subgroups. The first consists of the open water and sand dwelling species with males usually sporting bright colors while the females show a silvery coloration with irregular black bars or various other markings. The second subgroup is known locally and popularly as mbuna, which means rockdweller. Mbuna are smaller, generally vegetarian, and both sexes are often quite colorful, though many species are dimorphic. The second group, the tilapiines, consists of the only substrate-spawning species in the lake (Tilapia rendalli), as well as the 4 species of chambo (Nyasalapia). Maylandia and Labidochromis are popular cichlids in the international aquarium scene. Cichlids are an important export for Malawi, but wild populations are increasingly threatened by overfishing and localized pollution. Other wildlife resident in the lake includes crocodiles, and a large population of fish eagles which feed off the fish population.
The lake also supports populations of snails some of which carry bilharzia. For many years this was strenuously denied by the government, which feared it would deter tourism in the area, but since the fall of Hastings Banda, the presence of bilharzia in the lake has been more widely acknowledged. (However, due to the overfishing of snail eating cichlids in the lake, this has caused what little bilharzia did exist to greatly increase to the point of being a hazard to bathers in the south east portion of the lake.)

CICHLID HYBRID

Because of the introduced nile perch and water hyacinth, deforestation causing siltation of water, and overfishing, many species of Lake Victoria cichlids have been wiped out or drastically reduced in the wild. Thankfully, the myriad of satellite lakes surrounding Lake Victoria have not been affected, and harbor a vast array of similar species.

Some cichlids have been found to hybridise with closely related species quite readily, both in the wild and under artificial conditions.[23] This is not particularly unusual, having been observed among other groups of fishes, such as European cyprinids.[24] What is unusual is the extent to which cichlid hybrids have been put to commercial use, in particular as fast-growing food fish and as aquarium fish.[25][26] A notable hybrid, known as blood parrot cichlid, has caused controversy among aquarium enthusiasts. Some has called the fish "the Frankenstein monster of the fish world." [27]

Cichlid keeping aquarists tend to divide cichlids into groups based on regions such as Central America, South America, Madagascar and India, Lake Tanganyika, Lake Malawi and Lake Victoria. Others divide the cichlids using the combination of geographical, taxonomical, and behavioral criteria. Some notable groups resulting from this type of categorizing are the mbunas, haplochromines, dwarf cichlids, and shell dwellers.
Cichlids from Lake Tanganyika were first collected by German hobbyists during the 1930's. However, it was during the 1970s and 80s that the cichlids from lakes Tanganyika and Malawi began to become popular aquarium fishes. This trend continues to the present unabated.
Perhaps the most commonly encountered species in retail aquariums is Pterophyllum scalare from the Amazon River basin in tropical South America, known in the trade as the "angelfish". Other cichlids commonly stocked by retail aquaria include:

CICHLID REPRODUCTION

All species show some form of parental care for both eggs and larvae, often extended to free-swimming young until they are several weeks or months old.
The discus fish (Symphysodon species) are noted to feed their young with a secretion on the skin from slime glands. Other South American, some Central American and Madagascan cichlds have also been observed with fry feeding on their parents, but not to the extent of the discus.
Parental care falls into one of three categories: mouthbrooders, substrate brooders, and delayed mouthbrooding where the eggs are laid in the open or in a cave, and subsequently brooded in the mouth(s) of the parents. The mouthbrooding strategy for reproduction is primarily found in cichlids indiginous to the Great Rift Lakes in Africa, with South/Central American/New World cichlids tending to be substrate spawners. Mouthbrooding cichlids will generally have the female of the species immediately taking the newly fertilized eggs into her mouth where they will remain until the fry are free swimming. Some species of mouthbrooders will take food while brooding, while others will go the entire incubation period without taking any food. Most cichlids are maternal mouthbrooders, with some exhibiting bi-parental mouthbrooding, where both parents will take a turn holding the eggs in their mouth. Some mouthbrooders will release their fry once free-swimming and show no further parental care while other mouthbrooders will remain continue to guard the fry allowing them back into the mouth to escape predators. The ability to mouthbrood is thought to have been an evolutionary adaptation to reduce fry predation, likely due to the fishes being located in densely populated waters.

CICHLID DIET

Cichlids are astonishingly diverse in terms of diet. Many are primarily herbivores feeding on algae (e.g. Petrochromis) and plants (e.g. Etroplus suratensis) and small animals, particularly invertebrates, are only a small part of their diet. Some cichlids are detritvores and eat all types of organic materia; among these species are the tilapias of the genera Oreochromis, Sarotherodon, and Tilapia.
Other cichlids are predatory and eat little if any plant matter. These include generalists that catch a variety of small animals including other fishes and insect larvae (e.g. Pterophyllum), as well as variety of specialists. Trematocranus is a specialised snail-eater, while Pungu maclareni feeds on sponges. A number of cichlids feed on other fish, either whole or in part. Crenicichla are stealth-predators that lunge at small fish that pass by their hiding places, while Cichla are open water pursuit predators that chase down their prey. Paedophagous cichlids such as Caprichromis species eat other species' eggs or young (in some cases ramming the heads of mouthbrooding species to force them to disgorge their young). Among the more unusual predators are Plecodus straeleni feeds on scales and fins ripped from other fishes, and Nimbochromis livingstonii, which lies on its side and plays dead, hoping to lure smaller fish close enough for it to snap them up.
Scientists believe it is this wide adaptability of feeding styles that has helped cichlids to inhabit such a wide range of habitats. It is largely the pharyngeal teeth (teeth in the throat) that allows the cichlid so many 'niche' feeding behaviors, i.e. the jaws may be used to hold or pick food, while the pharyngeal teeth are used to crush what was harvested.

CICHLID RANGE

Cichlids are mainly freshwater fish that are most diverse in Africa and South America, with at least 900 species in the former and 290 in the latter.[14] Substanial numbers are also found in Central America as far north as the Rio Grande in southern Texas, and Madagascar has its own distinctive fauna of cichlids phylogenetically only distantly related to those on the African mainland. [15] [16] Endemic cichlids are largely absent in Asia except for four species in the Middle East, one in Iran, and three in the Indian Subcontinent.[17] Europe, Australia, Antarctica, and most of North America do not have any native cichlids, although where environmental conditions are suitable, for example in Florida and northern Australia, feral populations of cichlids have become established as exotics. [18] [19]
Cichlids are less commonly found in brackish and salt water habitats, though many species will tolerate brackish water for extended periods; Cichlasoma urophthalmus, for example, is equally at home in freshwater marshes and mangrove swamps, and can be found living and breeding in salt water environments such as the mangrove belts around barrier islands. [20] However, only a few cichlids are found primarily in brackish or salt water, most notably Etroplus maculatus, Etroplus suratensis, and Sarotherodon melanotheron

GET TO KNOW THE CICHLID FISH

Cichlids are members of a group of perciform fish known as the Labroidei alongside the wrasses Labridae, damselfish Pomacentridae, and surfperches Embiotocidae. This very large grouping shares a single key trait: the fusion of the lower pharyngeal bones into a single tooth-bearing structure. A complex set of muscles allows the upper and lower pharyngeal bones to be used as a second set of jaws for processing food, allowing a division of labour between the "true jaws" (mandibles) and the "pharyngeal jaws". Cichlids in particular have evolved to be very efficient feeders that are able to capture and process a very wide variety of food items and this is assumed to be one reason why they are so diverse (see section on diet below).[11]
The particular features of cichlids that distinguish them from the other Labroidei include:[12]
A single nostril on each side of the forehead instead of two.
No bony shelf below the orbit of the eye.
The lateral line organ is divided into two sections, one on the upper half of the flank and a second along the midline of the flank from about halfway along the body to the base of the tail (except for genera Teleogramma and Gobiocichla).
A distinctively shaped otolith.
The small intestine leaves the stomach from its left side, not from its right side as in other Labroidei.
Extensive brood care, with eggs and fry being guarded by one or both parents