“We have been overlooking how important cooperation is,” UCLA molecular biologist James A. Lake said. “If two prokaryotes get together, they can change the world. They restructured the atmosphere of the Earth. It’s a message that evolution is giving us: Cooperation is a way to get ahead.”

Lake discovered the first exclusively prokaryote endosymbiosis. All other known endosymbioses have involved a eukaryote — a cell that contains a nucleus. Eukaryotes are found in all multicellular forms of life, including humans, animals and plants.

“This relationship resulted in a totally different type of life on Earth,” said Lake, a UCLA distinguished professor of molecular, cell and developmental biology and of human genetics. “We thought eukaryotes always needed to be present to do it, but we were wrong.”

Lake reported that two groups of prokaryotes — actinobacteria and clostridia — came together and produced “double-membrane” prokaryotes.

“Higher life would not have happened without this event,” Lake said. “These are very important organisms. At the time these two early prokaryotes were evolving, there was no oxygen in the Earth’s atmosphere. Humans could not live. No oxygen-breathing organisms could live.”

The oxygen on the Earth is the result of a subgroup of these double-membrane prokaryotes, Lake said. This subgroup, the cyanobacteria, used the sun’s energy to produce oxygen through photosynthesis. They have been tremendously productive, pumping oxygen into the atmosphere; we could not breathe without them. In addition, the double-membrane prokaryotic fusion supplied the mitochondria that are present in every human cell, he said.

“This work is a major advance in our understanding of how a group of organisms came to be that learned to harness the sun and then effected the greatest environmental change the Earth has ever seen, in this case with beneficial results,” said Carl Pilcher, director of the NASA Astrobiology Institute, headquartered at the NASA Ames Research Center in Moffett Field, Calif., which co-funded the study with the National Science Foundation.

“Along came these organisms — the double-membrane prokaryotes — that could use sunlight,” Lake said. “They captured this vast energy resource. They were so successful that they have more genetic diversity in them than all other prokaryotes.

“We have a flow of genes from two different organisms, clostridia and actinobacteria, together,” he said. “Because the group into which they are flowing has two membranes, we hypothesize that that was an endosymbiosis that resulted in a double membrane. It looks as if a single-membrane organism has engulfed another. The genomes are telling us that the double-membrane prokaryotes combine sets of genes from the two different organisms.”

For this study whuch will be published in Nature, Lake has looked back more than 2.5 billion years. He conducted an analysis of the genomics of the five groups of prokaryotes.

A DAILY GALAXY ARTICLE. Courtesy – daily galaxy.

A daily galaxy article

For a decade or so, brain studies have seemed on the brink of answering questions about the nature of consciousness, the self, thought and experience. But they never do, argues University of California at Berkeley philosopher Alva Noë, because these things are not found solely in the brain itself.

In his new book, “Out of Our Heads: Why You Are Not Your Brain, and Other Lessons From the Biology of Consciousness,” Noë attacks the brave new world of neuroscience and its claims that brain mechanics can explain consciousness. Nobel Prize-winning molecular biologist Francis Crick wrote, “You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules.” While Noë credits Crick for drawing popular and scientific attention to the question of consciousness, he thinks Crick’s conclusions are dead wrong and dangerous.

Noe’s conversational style is gentle, attentive and easygoing. But, in true philosopher fashion, he also picks his words deliberately, as if stepping off the path of right thinking would result in some tragic plummet into the abyss of illogic.

In San Francisco there’s a brain gym where members exercise their brains with “neurobic” software. A sign outside the place reads: “You Are Your Brain!” It has become almost a mainstream notion now. But the subtitle of your book begins “Why you are not your brain.” What’s wrong with the “You are your brain” view?

It’s one thing to say you wouldn’t be you if not for your brain, that your brain is critical to what you are. But I could say that about your upbringing and your culture, too. It’s another thing entirely to say that you are your brain.

The findings add to a growing body of evidence that virtually all animals, including fish, shellfish and insects, can suffer.

Robert Elwood, the lead author of both papers, explained to Discovery News that pain allows an individual to be “aware of the potential tissue damage” while experiencing “a huge negative emotion or motivation that it learns to avoid that situation in the future.”

Both pain and stress are therefore key survival mechanisms.

Elwood, a professor in the School of Biological Sciences at The Queen’s University in Belfast, and colleague Mirjam Appel studied hermit crabs collected from rock pools in County Down, Northern Ireland. All of the crabs survived the experiments and were later released back into their native habitat.

Elwood and Appel gave small electric shocks to some of the crabs within their shells. When the researchers provided vacant shells, some crabs — but only the ones that had been shocked — left their old shells and entered the new ones, showing stress-related behaviors like grooming of the abdomen or rapping of the abdomen against the empty shell.

“Studies in rodents show that non-neuronal cells are part of information processing,” said Dr. Maiken Nedergaard of the University of Rochester Medical Center, who led the research team. “And our study suggests that astrocytes are part of the higher cognitive functioning that defines who we are as humans.”

The scientists noted there are 10 times as many astrocytes in the brain than the neurons that send electrical signals.

Medical student Nancy Ann Oberheim, first author of the study, said human astrocytes signals are faster, bigger and more complex than those found in mice and rats.

The researchers discovered new types of astrocytes, and also determined astrocytes use calcium, rather than electrical signals, to communicate with neurons. The research team reported astrocytes send much slower signals that do neurons, but are just as important in the basic working of the brain.

The study that included scientists from New York Medical College and the University of Washington appears in the Journal of Neuroscience.

In daily life, the number of brain networks recruited for understanding spoken language varies depending on the types of communication-related visual cues available, proposes a team led by neuroscientist Jeremy Skipper, now at Weill Medical College of Cornell University in New York City.

This idea contrasts with a longstanding notion that language comprehension is handled solely by a relatively narrow set of brain regions.

The networks in the brain that process language change from moment to moment during an actual conversation, using whatever information is available to predict what another person is saying,” Skipper says.

Neuroscientist Gregory Hickok of the University California, Irvine interprets the new findings more cautiously. Skipper’s results suggest that a stable language network can incorporate information from gestures and other visual signals that feed into it, Hickok remarks.

Skipper and his colleagues studied 12 adults who reclined in an fMRI scanner. Each volunteer listened to a woman read roughly 50-second-long adaptations of Aesop’s Fables. In one condition, participants only heard the woman’s voice. In three additional conditions, a mirror inside the scanner allowed them also to see the woman on a video screen placed at the edge of the scanner.

A science news article.

The gene is active in soldier ants, particularly in five neurons in the front of their brain, where it generates large amounts of its product, a protein known as PKG. The exact amount of the protein in the ants’ brains is critical to their behavior.

Low levels of PKG predispose both castes of ant to foraging; high levels make the soldiers fight and the foraging caste less interested in food gathering, Christophe Lucas and Marla B. Sokolowski report in the current issue of The Proceedings of the National Academy of Sciences.

The soldier and foraging castes in the species of ant under study, known as Pheidole pallidula, have their career choices settled in infancy when they start to be fed different diets. The soldiers develop large heads and jaws, and go on to guard the colony and kill invaders. The foragers, who remain small, specialize in looking for food and bringing back prey to the nest.

The mice, which are engineered to express a mutated protein that causes neurons in the cerebellum to die, move backwards when they try to walk forwards on a smooth surface. The same neurons are destroyed in cerebellar ataxia, which causes unsteadiness and loss of co-ordination.

Moonwalking – made famous by Michael Jackson – is a dance move where someone appears to walk forwards but actually slides backwards. The mice seem to do it because they place their feet further apart than normal as they walk, in order to maintain their balance.

Humans with cerebellar ataxia have trouble coordinating their movements, although “I don’t think there are any human patients out there who walk backwards,” says Esther Becker of the University of Oxford, who led the study.

“The million dollar question is whether mutations of this gene also occur in humans with cerebellar ataxia,” says Becker, who is currently screening patients with genetic forms of the condition to find out. If they do, it could pave the way towards new treatments.

Stephanie Hampton, the Deputy Director of the National Center for Ecological Analysis & Synthesis (NCEAS) who has been studying the lake shared with The Daily Galaxy what makes Baikal so exquisite.

“Lake Baikal probably the most beautiful place I’ve ever been – I’m thinking especially right now of the day I spent on Olkhon Island when the wildflowers were spectacular and the serenity was awe-inspiring. It is the world’s most ancient lake with a proliferation of biodiversity that is breathtaking,” describes Hampton affectionately.

“Where I would usually see 2 species of a particular type of crustacean (amphipods, in this case), instead I see 344 species in all shapes and colors and sizes. Many of the unique fish in Baikal resemble deep-sea fishes rather than other freshwater fish that are more closely related to them – with big eyes and spindly bodies. Also, sponge forests are common. If you are surprised that I’m mentioning a sponge forest in a lake, it’s for a good reason: they are not that common in lakes!” Hampton notes with enthusiasm, “So here you are in this incredibly cold lake at fairly high latitude, and underwater, this sponge forest looks more like the Caribbean than the subarctic!  It is really like a freshwater Galapagos in the midst of Siberia.”

It doesn’t take much prodding to get information out of Hampton when it comes to the lake! Her abounding awe and reverence for one of Mother Nature’s most unique wonders is completely apparent. Unfortunately, according to Hampton and other experts, all this is about to change forever. Global warming has had a strong impact on the lake, and is threatening its incredibly unique life forms that evolved to live only in extreme cold. A multi-generational study involving careful and repeated sampling over six decades was recently reported in the journal Global Change Biology showing that the lake’s temperatures is rising dangerously fast. Hampton, who participated in the study, notes that the lake was expected to be among those most resistant to climate change, due to its tremendous volume and unique water circulation. But unfortunately, that does not appear to be the case.

“So many organisms in and around Lake Baikal have evolved only in Lake Baikal, and they are very well-adapted to an extremely cold environment that is covered by ice for much of the year. More than half of the animals in Baikal are not found anywhere else! Lake Baikal has been around for 25 million years, so there has been plenty of time for organisms to evolve to its special environment – the warming associated with climate change is very abrupt, and it’s not clear whether or how these special organisms can adapt to a rapidly warming lake,” Hampton explains.

Already there has been a rise in more common water organisms in the lake—a sight that does not bode well for the lakes original inhabitants.

“We know that Siberia is one of the most rapidly warming regions of the world – the air temperature in Siberia has warmed at a rate that is about twice that of the average global rate of temperature increase. So when we approached this work with the Lake Baikal temperature data, we knew that the lake would have been exposed to a greater ambient temperature increase than lakes in other regions, but I certainly will admit to being surprised that the lake had warmed so rapidly since 1946. Why is it warming so much faster than the air? The answer probably involves ice,” Hampton explains.

A daily galaxy article