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Blobrana


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RE: Evolution
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Flawed analysis casts doubt on years of evolution research

Years of research on the evolution of ancient life, including the dinosaurs, have been questioned after a fatal flaw in the way fossil data is analysed was exposed by scientists from the universities of Reading and Bristol.
Studies based on the apparently flawed method have suggested Earths biodiversity remained relatively stable close to maximum carrying capacity - and hinted many signs of species becoming rapidly extinct are merely reflections on the poor quality of the fossil record at that time.
However, new research by scientists at the University of Reading suggests the history of the planets biodiversity may have been more dynamic than recently suggested, with bursts of new species appearing, along with crashes and more stable periods.
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Blobrana


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1860 Oxford evolution debate
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The 1860 Oxford evolution debate took place at the Oxford University Museum on 30 June 1860, seven months after the publication of Charles Darwin's On the Origin of Species. Several prominent British scientists and philosophers participated, including Thomas Henry Huxley, Bishop Samuel Wilberforce, Benjamin Brodie, Joseph Dalton Hooker and Robert FitzRoy. The debate is best remembered today for a heated exchange in which Wilberforce supposedly asked Huxley whether it was through his grandfather or his grandmother that he claimed his descent from a monkey.
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Blobrana


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Evolution in Action

With support from the National Science Foundation (NSF), Larry Gilbert and his colleagues are studying a population of Heliconius butterflies that they think is in the process of evolving into two distinct species. It's known as "speciation" when one species branches into two that no longer interbreed, and for Heliconius, the process involves those colour patterns.
While evolution is unfolding all the time, it is rare for scientists to be able to observe it up close, as they are doing now with a population of Heliconius in Ecuador. The simplest reason for a split in any family tree is geography.
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Blobrana


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Space is the final frontier for evolution, a study suggests.
It proposes that Charles Darwin may have been wrong when he argued that competition was the major driving force of evolution.
He imagined a world in which organisms battled for supremacy and only the fittest survived.
But new research identifies the availability of "living space", rather than competition, as being of key importance for evolution.
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Blobrana


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Evolutionary game of rock-paper-scissors may lead to new species

A new study in PNAS of the side-blotched lizard (Uta stansburiana) may bolster the idea that 'morphs', morphologically distinct types often found within species, could be the raw material for speciation.
Previous research has shown that competition among male side-blotched lizards takes the form of a rock-paper-scissors game in which each mating strategy beats and is beaten by one other strategy. Males with orange throats can take territory from blue-throated males because they have more testosterone and body mass. As a result, orange males control large territories containing many females.

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Blobrana


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Lilliput effect
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Evolution after extinction: New fossils force rethink

Mass extinctions have devastated biodiversity many times over the past 540 million years, according to scientists. After each cataclysmic event the species that survived diversified and filled the planet with life again.
Until now the fossil record supported the theory that species that survived extinction events--which ranged from meteorite impacts to an eruptions of super volcanoes (and in our time the mass destruction of ecosystems by humans)--did so in much smaller forms. This "Lilliput effect," in which post-extinction life is downsized, was believed to have persisted for millions of years.
But now a new fossil discovery in the U.S. by a team of French, German, Swiss, and American scientists may change what we know about the evolution of species after an extinction crisis.
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Blobrana


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RE: Evolution
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The evolution of evolution

Just suppose that Darwin's ideas were only a part of the story of evolution. Suppose that a process he never wrote about, and never even imagined, has been controlling the evolution of life throughout most of the Earth's history. It may sound preposterous, but this is exactly what microbiologist Carl Woese and physicist Nigel Goldenfeld, both at the University of Illinois at Urbana-Champaign, believe. Darwin's explanation of evolution, they argue, even in its sophisticated modern form, applies only to a recent phase of life on Earth.
At the root of this idea is overwhelming recent evidence for horizontal gene transfer - in which organisms acquire genetic material "horizontally" from other organisms around them, rather than vertically from their parents or ancestors. The donor organisms may not even be the same species. This mechanism is already known to play a huge role in the evolution of microbial genomes, but its consequences have hardly been explored. According to Woese and Goldenfeld, they are profound, and horizontal gene transfer alters the evolutionary process itself. Since micro-organisms represented most of life on Earth for most of the time that life has existed - billions of years, in fact - the most ancient and prevalent form of evolution probably wasn't Darwinian at all, Woese and Goldenfeld say.
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Blobrana


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Coral reefs are evolution hotspot

Coral reefs give rise to many more new species than other tropical marine habitats, according to a new study.
Scientists used fossil records stretching back 540 million years to work out the evolution rate at reefs.
They report in the journal Science that new species originate 50% faster in coral reefs than in other habitats.
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Blobrana


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Red Queen hypothesis of gradual evolution undermined.

New species might arise as a result of single rare events, rather than through the gradual accumulation of many small changes over time, according to a study of thousands of species and their evolutionary family trees.
This contradicts a widely accepted theory of how speciation occurs: that species are continually changing to keep pace with their environment, and that new species emerge as these changes accrue.
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Blobrana


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150 years ago today, on the 24th November, 1859,  the book "On the Origin of Species" was published.

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