Evolution Diary

Italian wall lizards introduced to a tiny island off the coast of Croatia are evolving in ways that would normally take millions of years to play out, new research shows.

In just a few decades the 5-inch-long (13-centimeter-long) lizards have developed a completely new gut structure, larger heads, and a harder bite, researchers say.

In 1971, scientists transplanted five adult pairs of the reptiles from their original island home in Pod Kopiste to the tiny neighboring island of Pod Mrcaru, both in the south Adriatic Sea.

Genetic testing on the Pod Mrcaru lizards confirmed that the modern population of more than 5,000 Italian wall lizards are all descendants of the original ten lizards left behind in the 1970s.
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A spectacularly preserved new Chinese fossil reveals a previously unseen stage in the early evolution of flight.

Called Eoconfuciusornis, it is a missing link between the oldest known bird, Archaeopteryx, and more advanced birds that have been discovered in the Yixian geological formation in China.

Eoconfuciusornis is a missing link between the oldest known bird, Archaeopteryx, and more advanced birds (Image: University of Bristol)

The Yixian deposits have yielded remarkably diverse fauna that have revolutionised avian palaeontology, but they are limited to a period from 125 to 120 million years ago – too narrow a time span to show much evidence of evolution within bird lineages.

A huge interval separates the Yixian birds from Archaeopteryx, which lived about 150 million years ago, leaving a gap in scientists’ knowledge of bird evolution over this period.

Toothless beak

But Eoconfuciusornis, was found in different deposits, known as the Dabeigou formation, and falls within the gap – radiometric dating shows it lived 131 million years ago.
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A new study of ancient proteins retrieved from a Tyranosaurus rex fossil confirms the long-hypothesized evolutionary connection between dinosaurs and modern birds, experts say.

The finding is the first molecular evidence that birds, not lizards or other reptiles, are the closest living relatives of dinosaurs, the researchers note.

A close relationship between the two groups was already widely suspected, based on similarities in skeletal features.

The new research follows a breakthrough study last year in which scientists reported the recovery and partial molecular sequencing of T. rex and mastodon proteins.

Both dinosaur studies examined samples of collagen, the main protein component of bone.
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The genetic split in Africa resulted in distinct populations that lived in isolation for as much as 100,000 years, the scientists say.

This could have been caused by arid conditions driving a wedge between humans in eastern and southern Africa.

Details have been published in the American Journal of Human Genetics.

It would be the longest period for which modern human populations have been isolated from one another.

But other scientists said it was still too early to reconstruct a meaningful picture of humankind’s early history in Africa. They argue that other scenarios could also account for the data.

At the time of the split - some 150,000 years ago - our species, Homo sapiens , was still confined to the African continent.

The results have come from the Genographic Project, a major effort to track human migrations through DNA.
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A fish species, which is all female, has survived for 70,000 years without reproducing sexually, experts believe.

Scientists from the University of Edinburgh think the Amazon Molly may be employing special genetic survival “tricks” to avoid becoming extinct.

The species, found in Texas and Mexico, interacts with males of other species to trigger its reproduction process.

The offspring are clones of their mother and do not inherit any of the male’s DNA.

Typically, when creatures reproduce asexually, harmful changes creep into their genes over many generations.

The species will eventually have problems reproducing and can often fall victim to extinction.

Scientists at Edinburgh University have been studying complex mathematical models on a highly powerful computing system to look at the case of the Amazon Molly.
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