Number 85 - To see a tree asmiling.

Hi all - great to have a crowd again. Good clicking everyone. And have a good rest of the weekend.

A nice Sun clicking day. Hope everyone had as good a day.

I see another tree asmiling.

Had to come back --- The Caboys are playing the Redskins tonight.
It reminded me of a funny that Willard Scott said during the morning news this week - er - last week now. He was doing his Smuckers over a hundred segment from Washington DC and as he passed the buck back to NY he said, "And now we go back to Matt from DC where we spend your money."

He's funny - but correct.

That was a good one. Enjoy your game.

Thanks, sumac -----

Grrrrrr, damn Caboobs looked and played like a High School team......... Man, I don't know what happened to them, but that wasn't the Caboys playing.

Ratsle fratzle ripple pipple thinkle people.

Good morning wildclickers. Clicked at this end and off to read interesting stuff.

Niners and Raiders both lost their opener games...hope it isn't 'things to come' for the season. Fell on their butts they did.

Beautiful weather here for another few weeks...got the Fall color wind catcher goin from the porch...and working dawn till dusk finishing paint, etc. and so looking forward to sittin' and reading for a month!

A few more hectic days...

Stradee, usually hectic days turn halcyon on rememberance.

eptember 13, 2010

Hybrids May Thrive Where Parents Fear to Tread

By SEAN B. CARROLL

On May 15, 1985, trainers at Hawaii Sea Life Park were stunned when a 400- pound gray female bottlenose dolphin named Punahele gave birth to a dark-skinned calf that partly resembled the 2,000-pound male false killer whale with whom she shared a pool. The calf was a wholphin, a hybrid that was intermediate to its parents in some characteristics, like having 66 teeth compared with the bottlenose’s 44 and the 88 of the false killer whale, a much larger member of the dolphin family.

In 2006, a hunter in the Canadian Arctic shot a bear that had white fur like a polar bear’s but had brown patches, long claws and a hump like a grizzly bear’s. DNA analysis confirmed the animal was a hybrid of the two species.

While one might think that these oddities are examples of some kind of moral breakdown in the animal kingdom, it turns out that hybridization among distinct species is not so rare. Some biologists estimate that as many as 10 percent of animal species and up to 25 percent of plant species may occasionally breed with another species. The more important issue is not whether such liaisons occasionally produce offspring, but the vitality of the hybrid and whether two species might combine to give rise to a third, distinct species.

While several examples of human-bred animal hybrids are well known and can thrive in captivity including zorses (zebra-horse), beefalo (bison-beef cattle) and, of course, mules (donkey-horse), naturally occurring animal hybrids have many factors working against their longer-term success.

One of the main obstacles is that, even if members of different species might mate, when the two species are too distant genetically or carry different numbers of chromosomes, the offspring are usually inviable or infertile (like zorses and mules), and are therefore evolutionary dead ends. A second problem is that any hybrid will usually be vastly outnumbered and outcompeted by one or both parent species.

But because species hybrids create new combinations of genes, it is possible that some combinations might enable hybrids to adapt to conditions in which neither parent may fare as well. Several such examples are now known from nature. Furthermore, DNA analysis is now allowing biologists to better decipher the histories of species and to detect past hybridization events that have contributed new genes and capabilities to various kinds of organisms including, it now appears, ourselves.

The familiar sunflower has provided great examples of adaptation by hybrids. Loren H. Rieseberg of the University of British Columbia and colleagues have found that two widespread species, the common sunflower and prairie sunflower, have combined at least three times to give rise to three hybrid species: the sand sunflower, the desert sunflower, and the puzzle sunflower.

The parental species thrive on moist soils in the central and Western states, but the hybrids are restricted to more extreme habitats. The sand sunflower, for instance, is limited to sand dunes in Utah and northern Arizona and the puzzle sunflower to brackish salt marshes in West Texas and New Mexico.

The species distributions suggest that the hybrids thrive where the parents cannot. Indeed, recent field tests that examined the relative ability of the parental species to thrive in the hybrids’ habitat, and vice versa, found that the sand sunflower was better able than its parents to germinate, grow and survive in its dune habitat but fared relatively poorly in parental habitats. Similarly, the puzzle sunflower was much better at growing in salty conditions than its parents.

One lesson from the sunflowers appears to be that hybrids may succeed if they can exploit a different niche from their parents. The same phenomenon has been discovered in animal hybrids.

In the past 250 years, various forms of honeysuckle have been introduced to the Northeastern states. In the late 1990s, researchers led by Bruce McPheron of Pennsylvania State University discovered that this invasive honeysuckle was infested by a particular fruit fly species they called the Lonicera fly. When they analyzed DNA to determine its relationship to others, they were stunned to find that it was a hybrid of two closely related flies, the blueberry maggot and the snowberry maggot.

In laboratory experiments, the researchers found that the Lonicera hybrid preferred its honeysuckle host plant over its parent species’ host plants and that each parent species preferred its own host plant over the other’s. However, both parents also accepted honeysuckle. The researchers suggest that since the two parental species were thus more likely to encounter each other on honeysuckle in the wild, the newly invasive weed served as a catalyst for matings between the species and the formation of the hybrid species that now prefers honeysuckle.

The sunflower and Lonicera fly examples raise the question of whether hybridization between species has been more frequent than biologists once assumed. The most provocative report of possible hybridization came from the recent analysis of more than 60 percent of the Neanderthal genome sequence, which raised the specter of our ancestors commingling their genes with a long-diverged cousin.

Analyses of the overall genetic distance between Neanderthals and modern humans reveal that our DNA is 99.84 percent identical to that of Neanderthals. This small divergence indicates that the two lines split off from each other about 270,000 to 440,000 years ago. The fossil evidence shows that Neanderthals were restricted to Europe and Asia, whereas Homo sapiens originated in Africa. Various kinds of evidence indicate that modern humans migrated out of Africa and reached the Middle East more than 100,000 years ago and Europe by about 45,000 years ago, and would have or could have encountered Neanderthals for some time in each locale. The crucial question for paleontology, archaeology, and paleogenetics has been what transpired between the two species. To put it a little more crudely, did we date them or kill them, or perhaps both?

If the former, then there could be a bit of Neanderthal in some or all of us. The first comparisons of small sections of Neanderthal DNA did not indicate any hybridization, and the lack of interbreeding became a widely accepted conclusion. That remained the case until this year, when a much greater portion of the Neanderthal genome was obtained by Svante Paabo and colleagues at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. It now appears that 1 percent to 4 percent of the DNA sequence of Europeans and Asians, but not Africans, was contributed by Neanderthals mixing with Homo sapiens, perhaps in the Middle East 50,000 to 80,000 years ago. It is possible that some Neanderthal versions of genes enabled modern humans to adapt to new climates and habitats.

The discovery of hybrid species and the detection of past hybridizations are forcing biologists to reshape their picture of species as independent units. The barriers between species are not necessarily vast, unbridgeable chasms; sometimes they get crossed with marvelous results.

Sean B. Carroll is a molecular biologist and geneticist at the University of Wisconsin.

September 13, 2010

Gulf May Avoid Direst Predictions After Oil Spill

By LESLIE KAUFMAN and SHAILA DEWAN

NEW ORLEANS — Marsh grasses matted by oil are still a common sight on the gulf coast here, but so are green shoots springing up beneath them.

In nearby bird colonies, carcasses are still being discovered, but they number in the thousands, not the tens of thousands that have died in other oil spills.

And at the mouth of the Mississippi River, the zone of severely oxygen-depleted water that forms every summer has reappeared, but its size does not seem to have been affected by the Deepwater Horizon spill.

How much damage resulted from almost five million barrels of oil pouring into the Gulf of Mexico is still being toted up in laboratories and government offices. It will be some time before the government releases its formal assessment of the effects — one that will define the scope of environmental restoration required by BP, Deepwater Horizon’s operator, and other companies.

Separately, scientists are arguing heatedly about how fast a large plume of dispersed oil more than a half-mile below the surface of the gulf is breaking down and how great a threat it poses to sea life.

Yet as the weeks pass, evidence is increasing that through a combination of luck (a fortunate shift in ocean currents that kept much of the oil away from shore) and ecological circumstance (the relatively warm waters that increased the breakdown rate of the oil), the gulf region appears to have escaped the direst predictions of the spring.

While its findings were disputed by some, the National Oceanic and Atmospheric Administration reported several weeks ago that the oil was breaking down and dispersing rapidly, probably limiting future damage from the spill.

And preliminary reports from scientists studying the effects on marshes, wildlife and the gulf itself suggest that the damage already done by the spill may also be significantly less than was feared — less, in fact, than the destruction from the much smaller Exxon Valdez spill in Alaska in 1989.

The scientists caution that much remains unknown, and that oil spills can have subtle effects that last for decades. Layers of oil are being found buried beneath the surface, both onshore and deep at sea. In blog posts from a research vessel in the gulf, Samantha Joye, a professor of marine sciences at the University of Georgia, reports that she observed a layer several centimeters thick on the sea floor, 16 miles from the wellhead, that she says was not a result of natural seepage.

But many scientists still say they are cautiously optimistic.

“Based on what I have seen so far, it could have been a lot worse,” said Lisa DiPinto, acting chief of NOAA’s marine debris division.

Perhaps no images evoked more heartbreak than those of the creatures inadvertently caught in the slick’s path: brown pelicans so covered with reddish oil that they could not lift their wings, sea turtles haplessly beached.

At the height of the spill, crates of birds arrived daily at a rehabilitation center in Fort Jackson, La.

Now the center is much quieter. On an August day, only about a dozen birds were brought in for rescue. But on the same day volunteers recovered more than twice as many dead birds, said Cathy Rezabeck, the spokeswoman for the Houma Joint Information Center run by BP and the government.

A similar pattern is being seen around the Gulf Coast, with the number of dead birds far exceeding the number of live ones being collected. Scientists attribute the rising death toll partly to the end of the nesting season — they can now go into the bird colonies to collect carcasses. They also believe fledglings have finally left the safety of their nests and are encountering residual oil.

Still, the numbers of oiled birds collected dead or alive — in the mid-7,000s as of Sept. 1 — is small compared with the avian toll of the Exxon Valdez. Carcasses of more than 35,000 birds were found immediately after that spill; 250,000 were believed to have died.

For the BP spill, said Melanie Driscoll, director of bird conservation for the Audubon’s Louisiana Coastal Initiative, “the final number will be in the thousands, not the tens of thousands.” Ms. Driscoll cited several reasons, including warmer temperatures, which make it easier for birds to regulate their body temperatures, and the inability of much of the oil to penetrate the marshes.

Assuming that the food chain remains healthy — and this remains a major question for scientists — even threatened birds like the brown pelican will come back, she said.

The spill also raised alarms about Kemp’s ridley sea turtles. Some 600 were stranded, more than seven times the usual number found from May to August, and 56 dead ones were collected, a majority with no visible signs of oil, suggesting they may have been killed by shrimpers. Rescuers scooped up hundreds of living, heavily oiled turtles from mats of sargassum seaweed where they congregate and feed.

Since mid-July, however, rescuers have found the sargassum mats not blackened but clean and teeming with food, and with them, turtles free of oil or so lightly oiled that they could be cleaned and released on the spot, said Dr. Brian Stacy, an NOAA veterinarian.

“I personally didn’t anticipate such a dramatic change so quickly,” he said.

Leland Hales, an environmental scientist inspecting marshy areas where oil had previously been seen, says much the same thing. Mr. Hales, who inspects previously oiled sites for BP, travels by boat to coordinates near Terrebonne Parish where his notes mention things like “10-by-10 yards oiled grass on the southeast” of an island of nesting terns.

In many cases, there is no longer anything to see. Oil has washed away, leaving grass that appears healthy. “I would have expected rapid die-off,” Mr. Hales said, “but that’s not what’s out there.”

The federal government estimated last month that half the oil leaked into the gulf had evaporated or otherwise been removed, leaving one quarter of it dissolved into tiny droplets and another quarter visible in forms like surface sheen and tar balls. The figures are controversial, and some scientists say they are vastly underestimated.

But according to NOAA’s figures, the BP spill oiled far less coastline than the Exxon Valdez spill. As of Aug. 31, NOAA had surveyed 1,796 miles of Louisiana coast and found 35 miles of shoreline to be heavily oiled, 71 miles to be moderately oiled and 115 miles to be lightly oiled. By contrast, the Exxon Valdez spill contaminated 1,300 miles of shoreline, about 200 miles of it heavily or moderately oiled, according to the Exxon Valdez Oil Spill Trustee Council.

Of the oil that did reach shore in the gulf, most has remained at the fringe of the dense marshes. That is largely good news for hundreds of thousands of acres of wilderness inside the fringe.

“The huge expanses of marshes that occur interiorly to the shoreline have been spared,” said Irving A. Mendelssohn, a professor of oceanography and coastal plant ecology at Louisiana State University.

Mr. Hales and other scientists say that even the oiled part of the marsh appears to be recovering.

Mark Kulp, an associate professor of coastal geology at the University of New Orleans, who also does research for a contractor for BP, says his observations of vegetation, from Spartina grasses to black mangrove forests, reveal a surprising rebirth. “There are places that I’ve seen where the stalks were laid over with oil and there is now new vegetation coming up through,” he said. “It is a pervasive thing.”

Marshes and wetlands are particularly sensitive to oil. If it enters the soil, it can kill grasses and their roots, leading to erosion. In some spills, including the Exxon Valdez, residual oil has been found in marshes decades later. Dr. Kulp suggests that will not be true for the gulf. “One thing working in our favor is the nature of the substrate,” he said, referring to the marsh bottom. “It is made dominantly of muddy sediment and is relatively impenetrable.”

Others are less sanguine. John W. Day Jr., a retired professor of oceanography and coastal sciences at Louisiana State, has worked with a private firm that developed a complex sensor for aerial detection of oil and gas. Its measurements show that plants in the marsh interior which appear healthy are, in fact, stressed and will probably soon die. Dr. DiPinto of NOAA is also concerned. She said that marsh creatures that dig burrows, like crabs, may eventually bring oil deeper into the soils.

And Wilma Subra, a chemist who provides technical assistance to the Louisiana Environmental Action Network and who has found substantial residual oil in marshes and estuaries near the mouth of the Mississippi River, the Atchafalaya River and Terrebonne Bay, said: “The government and BP continue to say it is very much improved out there, but there is still a lot of oil. Any fisherman could tell you that.”

Ms. Subra said the government needs to do more to assess the situation. “I am not saying their people in the field are not doing a good job, but there is a lot we are hearing about from fishermen and seeing ourselves that is not being investigated,” she said. “I’ve seen a lot of heavily oiled areas where the vegetation is not coming back.”

The spill’s greatest scientific challenge may be understanding how the oil is interacting with the undersea environment. The oil was released 5,000 feet beneath the water’s surface and then treated with an unprecedented volume of chemical dispersants. Some enormous fraction — how much is disputed — formed at least one great undersea plume of microscopic droplets.

Oil, which is toxic, poses a threat to wildlife, especially if continually ingested over time, though so far all seafood samples tested by the Food and Drug Administration have been ruled safe.

Still, scientists at Tulane University and the University of Southern Mississippi have reported finding tiny droplets of oil on blue crab larvae. The droplets have not been ingested but are lodged under the carapace, and seem to disappear when the larvae molt, said Harriet Perry, a biologist at Southern Mississippi. That suggests the droplets might affect animals that prey on the larvae more than the crabs themselves.

Scientists also worried that the plumes would severely deplete oxygen levels in the gulf because of a population explosion in oil-eating bacteria.

Low oxygen levels are already an acute concern. Every summer, agricultural runoff from the Mississippi stimulates the bacteria population, producing a “dead zone” the size of New Jersey, stretching from the mouth of the Mississippi River west to Galveston, Tex. The zone is so oxygen-depleted that it supports no life. Scientists, relying on data that did not include the oil spill, estimated in May that the zone would be somewhat larger this year.

But so far, there is little evidence of severe oxygen depletion outside the predicted zone. NOAA has taken more than 2,000 samples to measure oxygen levels, drawing water from the surface to the bottom within a radius of about 60 miles of the well site, said Steve Murawski, chief science adviser to NOAA’s National Marine Fisheries Program. They have found oxygen depression, but not levels too low to support fish, he said.

More recent findings, by Department of Energy scientists at the Lawrence Berkeley National Laboratory, suggest that the plume has already largely dispersed or degraded, though other scientists vigorously dispute that claim. The scientists at Lawrence were working under a grant from the EnergyBiosciences Institute at the University of California, Berkeley, which was financed several years ago by a 10-year, $500 million grant from BP.

Terry Hazen, a microbiologist and the head of the ecology department at the laboratory, said oxygen levels may have remained high because the droplets in the plume were so diffuse.

Dr. Hazen said a small part of him was disappointed that the plume had become undetectable, because it could no longer be studied.

“But that’s just the scientist in me,” he said. “The ecologist and environmentalist is glad that it’s gone — it was an ecological disaster.”

eptember 13, 2010

Tug of War Pits Genes of Parents in the Fetus

By NICHOLAS WADE

Under Mendel’s laws of inheritance, you could thank mom and dad equally for all the outstanding qualities you inherited.

But there’s long been some fine print suggesting that a mother’s and father’s genes do not play exactly equal roles. Research published last month now suggests the asymmetry could be far more substantial than supposed. The asymmetry, based on a genetic mechanism called imprinting, could account for some of the differences between male and female brains and for differences in a mother’s and father’s contributions to social behavior.

A person gets one set of genes from each parent. Apart from the sex chromosomes, the two sets are equivalent, and in principle it should not matter if a gene comes from mother or father. The first sign that this is not always true came from experiments in which mouse embryos were engineered to carry two male genomes, or two female genomes. The double male and double female mice all died in the womb. Nature evidently requires one genome from each parent.

Biologists then made the embryos viable by mixing in some normal cells. The surprising outcome was that mice with two male genomes had large bodies and small brains. With the double female genome mice, it was the other way around. Evidently the maternal and paternal genomes have opposite effects on the size of the brain.

The root of the asymmetry is a procedure called imprinting in which either the mother’s or the father’s copy of a particular gene is inactivated. The best worked out example concerns a gene called insulinlike growth factor-2, which promotes the growth of the fetus. The IGF-2 gene is active in the paternal genome but imprinted or inactivated in the genome the fetus receives from its mother.

The leading explanation for imprinting is a theory that invokes conflict between relatives. Developed by David Haig, an evolutionary biologist at Harvard, the theory holds that there is a clash of interests between the fetus, whose purpose is to extract as much nutrition as possible, and the mother, whose interests lie in allocating her resources evenly to all the other children she may bear in the future.

Over the course of evolution this conflict has come to be mediated at a genetic level, Dr. Haig’s explanation goes, because the mother and the father have different interests. Speaking of mammals in general, the conflict is driven by female promiscuity. The mother wants to share her resources among progeny who may have different fathers, whereas the father is interested in the survival of only his own child. So the father always confers the IGF-2 gene in active form and the mother always bequeaths it in imprinted or silent form. The gene is imprinted in mice, humans and many other mammals.

It may seem strange to have a genetic tug of war within the fetus, with the paternal copy of the IGF-2 gene always asking for more, and the maternal copy refusing to ask at all, but presumably over the course of evolution the individuals who carried these two warring copies of the gene left more offspring than those with the gene in any other form.

Until last month only a hundred imprinted genes were known, and the mechanism seemed just an interesting deviation from Mendelian genetics. Research led by Christopher Gregg and Catherine Dulac of Harvard has shown that imprinting is far more common and more intricate than supposed.

Working in mice, the Harvard team showed that around 1,300 genes are imprinted. Dr. Dulac said that she expects a substantial, though lesser, proportion to be imprinted in people — maybe some 1 percent of the genome — because humans are more monogamous than mice and so the parents’ interests are more closely aligned.

Dr. Dulac was able to detect so many new imprinted genes by taking advantage of the ease with which genes can now be decoded. She cross-bred two very different strains of mice, thus ensuring that the maternal and paternal versions of each gene would have recognizably different sequences of DNA.

When a gene is activated, the cell transcribes it into RNA, DNA’s close chemical cousin. By decoding all the RNA transcripts in the mouse’s cells, Dr. Dulac could pick out those genes in which the paternal version was being transcribed much more than maternal version, and vice versa.

Besides finding far more imprinted genes than expected, Dr. Dulac’s team also picked up unexpected patterns in the way the genes were expressed. Maternal genes were more active in the embryo’s brain, but paternal genes became more active in the adult.

In another novel pattern, she found sex differences in imprinted genes in different region of the brain, particularly those concerned with feeding and with mating behavior. A gene called interleukin-18 is activated from the mother’s version in two important regions of the brain. This asymmetry is of interest because the gene in people has been linked with multiple sclerosis, a disease that predominates in women.

Altogether Dr. Dulac found 347 genes where either the mother’s or the father’s copy was more actively expressed in certain regions of the brain. Sex differences in the brain are usually attributed to the influence of hormones, but sex-based differences in imprinting may be another mechanism by which nature spins male and female brains out of the same genome.

“In your brain, your mom and your dad keep telling you what to do — I keep laughing when I think about it,” Dr. Dulac said.

In the cortex of the brain, Dr. Dulac discovered another unexpected asymmetry. Women have two X chromosomes, one from the mother and one from the father. The usual rule is that in each cell either the mother’s or the father’s copy is chosen at random to be switched off. But in the neurons of the cortex, there is a much greater chance that the paternal X chromosome will be switched off. “So again, it’s the conflict between mom and dad — each tries to use different chromosomes to influence you,” Dr. Dulac said.

Dr. Haig says that his theory of imprinting explains not only the tug of war between mother and fetus but also why there are imprinted genes in the brain.

It all has to do with the different interests of the mother’s family and the father’s family, which tug the individual in different directions. Relatives get into the argument because they share varying proportions of an individual’s genes.

Evolutionary fitness depends on passing one’s genes on to the next generation. But it also counts to pass on the identical genes that have been co-inherited by one’s siblings, uncles and aunts. The doctrine, known as inclusive fitness, was proposed by the biologist William Hamilton in the 1960s and is widely accepted, though is not without critics. It was challenged last month in the journal Nature by the Harvard biologist E. O. Wilson and two colleagues.

Under inclusive fitness, Dr. Haig has pointed out, a conflict of interest between the mother’s and father’s relatives would have arisen because of the different dispersal patterns of men and women. Most often it has been the woman who leaves her ancestral village and goes to live with her husband’s family.

The maternal genes stand to gain if the woman is as selfish as possible and focuses just on her and her children’s welfare. But since the father is related to everyone else in the village, the father’s genes will gain from altruistic behavior. Such a conflict will result in imprinted genes, just like the battle between the mother and fetus over the mother’s resources, in Dr. Haig’s view.

Two evolutionary biologists, Francisco Ubeda of the University of Tennessee and Andy Gardner of the University of Oxford in England, have devised a mathematical model for assessing the consequences of a woman living in her husband’s village, among people to whom she is not related. Natural selection, they say in an article in the current issue of Evolution, will favor the activation of paternal genes that underlie altruistic behavior and maternal genes that promote selfishness. “Your paternal genes want you to be nicer to your neighbors than your maternal genes do,” Dr. Gardner said in an interview.

In most people the altruistic and selfish motives operate in some reasonable kind of balance. But the imprinted genes carry a serious vulnerability: since they are silenced, a mutation to the other copy can be disastrous. Diseases like autism may be connected with disruptions to imprinted genes, Dr. Gardner said.

Imprinting, far from being a genetic curiosity, may play a central role in sexual differences and in psychiatric disease, if Dr. Haig’s explanation is correct. Much of the available evidence comes from mice, and people may to some extent have emancipated themselves from imprinting when they evolved the pair bond system of mating about a million years ago. But the pair bond does not mean perfect monogamy, and in its deviations from perfection there is plenty of room for imprinting to thrive.

All clicked, and left alot of heavy duty reading for everyone. There will be a quiz after dinner.

s

You are something else my friend. Three very good and thoughtful articles. Wonderful and thank you.

Now. No. 1
I respect the thought into all the avenues of approach to genetics by the various scientists. However, in your eye is a very very old approach to this question = Donkeys. Donkeys cannot reproduce their species. The only way is human intervention = mate a mule with a horse. That's it.
Also, I totally agree with the authors take on Neanderthals. They are but ONE of thousands of offshoots of the Homosapien evolution. All branches of the tree that WE belong to are extinct (which by the way is normal)..... We are still here (at least for awhile) and nobody knows what is going to happen next. I believe the Neanderthals (what was left of them after the last Ice Age) evolved into our race of humanity. Now there is really good evidence that a natural disaster many hundreds of thousands of years ago killed off almost all life on earth. Homosapiens were numbered in the low thousands (approx 3000). Lately, DNA evidence has been proven that approx 90% of all people on earth have a gene from ONE single male ancestor. That is astounding.

WOW, what a guy!!!!!!!!!!!!!!!!!

Holy Cow........... here's No. 2
The Gulf thing --- damage to wildlife down there was not solely determined by breed or type --- it had to do with the migration activity of each animal. The time of migration saved a lot - the movement of the waters in the Gulf saved a lot - and we were damned lucky with the weather.
Now, on to something more missunderstood. The oil eating microbes. They have been in the Gulf region for a long long time and for a good reason. The oil wells leak oil. And as a result the microbes that eat oil are evolved.

No 3 Genes?
We should all remember this stuff from High School. DNA evidence was discovered during the 50's - We have just gotten better at it.

Thanks all for saving another tree today.

I need a nap

Will read tomorrow, sue. Interesting so far though.

As always, good to catch up with sumac's shortlisting of interesting articles.

Love to the WildClickers and their packs, human and otherwise.

Poor Eve!

Good God! Oil eating microbes! Evolved into what though!? scary

Same to you dear Beth

Morning all..............

Stradee, the earth has it's own way of surviving. The most dangerous and destructive things on earth are humans. We should treat Mother Nature better.....

Good clicking everyone.

Here is a site detailing the history of DNA ---- It's short.
http://www.dna-structure.com/history.htm

Thanks, Danon. I will come in to read it after I finish up my outside chores. All clicked here.

eptember 14, 2010

Fishing at the Base of the Pyramid

Perhaps the most abundant remaining source of wild protein on the planet is krill, a tiny crustacean that lives in Antarctic waters. It is fed upon by nearly every Antarctic species, including whales, penguins, seals and many kinds of fish. The species with the greatest appetite for protein is humans. That harvest has now increased enough to start worrying ecologists.

An article in Nature magazine on Sept. 1 warns that increased fishing “is adding to the pressure of environmental changes” already threatening krill. Since krill feed on algae that grow under the ice, they are especially susceptible to the effects of global warming.

None of the harvested krill turn up on consumers’ dinner plates as krill. Instead, it is ground up for fish meal for the aquaculture industry and processed into nutritional supplements. Meanwhile, no one is sure how many krill are out there. Estimates vary widely, from 100 million metric tons to perhaps 500 million metric tons.

The current harvest falls well within the agreed upon 5 million metric ton limit, but the commercial appetite is relentlessly growing. Norway has increased its fleet, and, for the first time, China is sending two krill boats to the southern ocean.

The treaty organization that sets the krill limit — the Convention on the Conservation of Antarctic Marine Living Resources — is scheduled to meet in October. It needs to establish fishing limits for specific areas instead of for whole oceans. It needs to work with its member nations to get a more accurate scientific picture of how krill are doing. Humans have overfished nearly every fishery. Overfishing krill would be especially destructive since it would threaten the food chain of the entire Antarctic.

Nice overview of the history of DNA.