World's largest flower

The flower with the world's largest bloom is the Rafflesia arnoldii. This rare flower is found in the rainforests of Indonesia. It can grow to be 3 feet across and weigh up to 15 pounds! It is a parasitic plant, with no visible leaves, roots, or stem. It attaches itself to a host plant to obtain water and nutrients. When in bloom, the Rafflesia emits a repulsive odor, similar to that of rotting meat. This odor attracts insects that pollinate the plant.

Source <www.loc.gov>

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Clownfish Change Size And Sex To Move Up The Ranks

What the movie "Finding Nemo" doesn't tell you about clownfish is that they're all transsexuals. In a study published in the journal Nature, evolutionary biologist Peter Buston and colleagues report that clownfish in Papua New Guinea reefs can change their sex at will for social reasons. Clownfish live in strict hierarchical communities. Each neighborhood is dominated by a top-ranking female breeder. Her male partner is next, followed by up to four progressively smaller, non-breeding fish. When the dominant female dies, her mate changes sex and becomes female. The top-ranking non-breeder becomes a sexually active male, and all the other fish shift up a rank. Clownfish also appear to regulate their size in order to remain part of the group. Each fish keeps its body mass 20 percent smaller than the fish directly above it in social rank, probably to avoid conflict. Fish who disrespectfully outgrow their rank are rejected by the clan.

Source <www.flmnh.ufl.edu>

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Meet X-woman: a possible new species of human

The human family tree may be in for a dramatic rewrite. DNA collected from a fossilised finger bone from Siberia shows it belonged to a mysterious ancient hominid – perhaps a new species.

"X-woman", as the creature has been named, last shared an ancestor with humans and Neanderthals about 1 million years ago but is probably different from both species. She lived 30,000 to 50,000 years ago.

"This is the tip of the iceberg," says Chris Stringer, a palaeoanthropologist at the Natural History Museum in London who was not involved in the find. More hominids that are neither Neanderthal nor human are likely to be discovered in coming years, particularly in central and eastern Asia, he says.

Roaming Asia

Previously, anthropologists thought that Neanderthals and humans were the only hominids roaming Europe and Asia during the late Pleistocene. The discovery of 17,000-year-old Homo floresiensis – the "hobbit" – dispelled that notion, but many anthropologists look on H. floresiensis as an anomaly, isolated from the human–Neanderthal hegemony on the mainland.

The newly discovered creature, which probably lived in close proximity to humans and Neanderthals, suggests that things were not that simple. "The picture that's going to emerge in the next years is a much more complex one," says Svante Pääbo, a palaeogeneticist at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Pääbo and colleague Johannes Krause discovered the specimen in the Denisova cave in southern Siberia, and sequenced DNA from its mitochondria. It is impossible to say what the creature would have looked like based on a single pinkie bone, so Pääbo and Krause are hesitant to call it a new species.

Though the creature's sex is not known, they are for now referring to her as X-woman because mitochondria are inherited maternally. "No one really knows what she would look like," Pääbo says.

X-woman's mitochondria differ from a human's at nearly 400 DNA letters; Neanderthals show only half as many differences.

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Intelligent people have 'unnatural' preferences and values that are novel in human evolution

More intelligent people are significantly more likely to exhibit social values and religious and political preferences that are novel to the human species in evolutionary history. Specifically, liberalism and atheism, and for men (but not women), preference for sexual exclusivity correlate with higher intelligence, a new study finds.

The study, published in the March 2010 issue of the peer-reviewed scientific journal Social Psychology Quarterly, advances a new theory to explain why people form particular preferences and values. The theory suggests that more intelligent people are more likely than less intelligent people to adopt evolutionarily novel preferences and values, but intelligence does not correlate with preferences and values that are old enough to have been shaped by evolution over millions of years."

"Evolutionarily novel" preferences and values are those that humans are not biologically designed to have and our ancestors probably did not possess. In contrast, those that our ancestors had for millions of years are "evolutionarily familiar."

"General intelligence, the ability to think and reason, endowed our ancestors with advantages in solving evolutionarily novel problems for which they did not have innate solutions," says Satoshi Kanazawa, an evolutionary psychologist at the London School of Economics and Political Science. "As a result, more intelligent people are more likely to recognize and understand such novel entities and situations than less intelligent people, and some of these entities and situations are preferences, values, and lifestyles."

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From a Distant Comet, a Clue to Life

For the first time, a building block of proteins — and hence of life as we know it — has been found in a comet.

That adds to the prevailing notion that many of the ingredients for the origin of life showered down on the early Earth when asteroids (interplanetary rocks orbiting the inner solar system) and comets (dirty ice balls that generally congregate in the outer solar system beyond Neptune) made impact with the planet.

In the new research, scientists at the Goddard Space Flight Center, in Greenbelt, Md., detected the amino acid glycine in comet bits brought back in 2006 by the NASA space probe Stardust.
“It tells us more about the inventory of organics in the early solar system,” said Jamie Elsila, an astrochemist at Goddard who led the research.

Amino acids are small molecules that, when strung together into chains, form a diversity of proteins. For four decades, scientists have found a multitude of amino acids in some meteorites, the bits of asteroids that land on Earth. More recently, astronomers reported that amino acids might float throughout the cosmos, a belief resulting from their detection of the color signatures of glycine, the simplest of the amino acids, in distant interstellar gas clouds.

Some doubts remain about that claim, but if it is true, it would then not be surprising that when the clouds condense into stars and planets, the building blocks of life might be readily available there.
As for our solar system, meteorite data show that amino acids are present in its inner neighborhood, where asteroids orbit, but until now nothing has been known for certain about what might have formed farther out, where comets gather.

But on Jan. 2, 2004, the Stardust spacecraft flew through the tail of dust and gas of the comet Wild 2 (pronounced vilt two). Two years later, the probe returned to Earth, sending collected samples to the ground by parachute for scientists to analyze. Comets are thought to preserve material of the early solar system, largely unchanged for the last 4.5 billion years.

Within a few months, the Goddard scientists found glycine embedded in aluminum foil of the collecting apparatus. They had spent the time since then confirming that the glycine indeed came from the comet and not from contamination.

“It’s not necessarily particularly surprising,” Dr. Elsila said of her extraterrestrial glycine in a phone conversation Tuesday. “I would have been surprised if it wasn’t there.”
Dr. Elsila and her colleagues were able to show that the glycine from the comet had heavier quantities of the isotope carbon 13 than what occurs on Earth. They also detected a second amino acid, beta-alanine, but the quantities were too minuscule to confirm.

The findings were presented Sunday at a Washington meeting of the American Chemical Society and will be published in the journal Meteoritics & Planetary Science.

Donald E. Brownlee, a professor of astronomy at the University of Washington and principal investigator of the Stardust mission, said the discovery indicated that the chemical reactions that produce glycine, and presumably other amino acids, occurred throughout the early solar system.

“That means production of amino acids is fairly common,” Dr. Brownlee said.
That had not been a foregone conclusion, he said. Some scientists had suggested that the chemical reactions might have required warm and wet conditions that existed in early asteroids but not comets.

Source http://www.nytimes.com/2009/08/19/science/space/19comet.html?ref=space

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New flying reptile fossils found

Researchers in China and the UK say they have discovered the fossils of a new type of flying reptile that lived more than 160 million years ago.

The find is named Darwinopterus, after famous naturalist Charles Darwin.
Experts say it provides the first clear evidence of a controversial type of evolution called modular evolution.
The 20 new fossils found in north-east China show similarities to both primitive and more advanced pterosaurs, or flying reptiles.
The research is published in the journal, Proceedings of the Royal Society B.

Missing link
Pterosaurs, sometimes called pterodactyls, were flying reptiles that flourished between 65 and 220 million years ago.

Until now, scientists had known about two distinct groups of these creatures - primitive, long-tailed pterosaurs and more advanced short-tailed ones, separated by a huge gap in the fossil record.
But the discovery of more than 20 new fossil skeletons in north-east China could be the missing link in this evolutionary chain.

Darwinopterus is a hawk-like reptile with a head and neck just like advanced pterosaurs - but the rest of the skeleton is similar to more primitive forms.
Researchers say that this could be evidence of what they call modular evolution - where natural selection forces a whole series of traits to change rapidly rather than just one.
With its long jaws and rows of sharp-pointed teeth, these creatures were very well suited to catching and killing other flying species.
The fossils were found in rocks that are 160 million years old, making them 10 million years older than the first bird, Archaeopteryx.

Source: here 

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Ardi's Secret: Did Early Humans Start Walking for Sex?

Jamie Shreeve Science editor, National Geographic magazine

October 1, 2009

The big news from the journal Science today is the discovery of the oldest human skeleton—a small-brained, 110-pound (50-kilogram) female of the species Ardipithecus ramidus, nicknamed "Ardi." She lived in what is now Ethiopia 4.4 million years ago, which makes her over a million years older than the famous Lucy fossil, found in the same region 35 years ago. (Full story: "Oldest 'Human' Skeleton Found—Disproves 'Missing Link.'") Buried among the slew of papers about the new find is one about the creature's sex life. It makes fascinating reading, especially if you like learning why human females don't know when they are ovulating, and men lack the clacker-sized testicles and bristly penises sported by chimpanzees. (See pictures of Ardipithecus ramidus.) One of the defining attributes of Lucy and all other hominids—members of our evolutionary lineage, including ourselves—is that they walk upright on two legs. While Ardi also walked on two legs on the ground, the species also clambered about on four legs in the trees. Ardi thus offers a fascinating glimpse of an ape caught in the act of becoming human. (Interactive: Ardi's key features.) The problem is it is doing it in the wrong place at the wrong time—at least according to conventional wisdom, which says our kind first stood up on two legs when they moved out of the forest and onto open savanna grasslands. At the time Ardi lived, her environment was a woodland, much cooler and wetter than the desert there today. So why did her species become bipedal while it was still living partly in the trees, especially since walking on two legs is a much less efficient way of getting about? According to Owen Lovejoy of Kent State University, it all comes down to food, and sex. Full Story HERE

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