Evolution

In a new paper, researchers writing in Current Biology show how lactase persistence variants tell the story about the ancestry of the Khoe people in southern Africa and that their pastoralist practices were probably brought to southern Africa by a small group of migrants from eastern Africa.


Although Neanderthals are extinct but fragments of their genomes persist in modern humans.

 These shared regions are unevenly distributed across the genome and some regions are particularly enriched with Neanderthal variants. An international team of researchers led by Philipp Khaitovich of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and the CAS-MPG Partner Institute for Computational Biology in Shanghai, China, have found that DNA sequences shared between modern humans and Neanderthals are specifically enriched in genes involved in the metabolic breakdown of lipids.


Why zebras have black and white stripes is a long-standind puzzle of evolution.

To find out, the researchers behind a Nature Communications paper mapped the geographic distributions of the seven different species of zebras, horses and asses, and of their subspecies, noting the thickness, locations, and intensity of their stripes on several parts of their bodies. Their next step was to compare these animals' geographic ranges with different variables, including woodland areas, ranges of large predators, temperature, and the geographic distribution of glossinid (tsetse flies) and tabanid (horseflies) biting flies.

They then examined where the striped animals and these variables overlapped.


Genghis Khan is famous in evolution because a giant chunk of the world carries is DNA. A recent story of brown bears shows that males roam much greater distances than females, and mating is part of the agenda. 


If you become saucer-eyed when afraid or you squint from disgust, it may not be cultural - it may be biology. Near-opposite facial expressions like squinting and being wide-eyes are rooted in emotional responses that exploit how our eyes gather and focus light to detect an unknown threat, according to a study by Adam Anderson, professor of human development in Cornell's College of Human Ecology, and colleagues.


Humans didn't cause problems for everything we get blamed for but DNA evidence in a paper suggests that the ancient New Zealand megaherbivore, moa, a distant relative of the Australian Emu, did go extinct shortly after Polynesians arrived  in the late 1200s.

All nine species of New Zealand moa, the largest weighing up to 250 kilograms, have been gone for centuries and other studies suggest that huge populations of moa had collapsed before people arrived and hence influences other than people were responsible for the extinction, like climate change killing the vegetation. Instead, the authors say humans killed the environment and that killed the moa.


Researchers have found the earliest fossil evidence for the presence of bone marrow in the fin of a 370 million-year-old fish,
Eusthenopteron, a Devonian lobe-finned fish from Miguasha in Canada that is closely related to the first tetrapods.


A new study finds that sea anemones display a genomic landscape with a complexity of regulatory elements similar to that of fruit flies or other animal model systems, which suggests that this principle of gene regulation is already 600 million years old and dates back to the common ancestor of human, fly and sea anemone.

But sea anemones are more similar to plants rather to vertebrates or insects in their regulation of gene expression by short regulatory RNAs called microRNAs.  


Cell metabolism is a crucial biological function for all living organisms but understanding how life may have emerged is difficult. And learning some answers may make it possible to learn whether it is possible for life to have emerged in similar environments on other worlds. 

Researchers writing in Astrobiology
detail their new approach to simulating the energetic processes that may have led to the emergence of cell metabolism.

Dr. Terry Kee from the School of Chemistry at the University of Leeds, one of the co-authors of the research paper, said, "What we are trying to do is to bridge the gap between the geological processes of the early Earth and the emergence of biological life on this planet."


Evolutionary biologists have long considered bird song to be an exclusively male trait, resulting from sexual selection. A new paper says that's not the whole story.


The results of their analysis, now published in Nature Communications, showed that the common ancestor of modern songbirds had female song.

It doesn't turn Darwin's theory of sexual selection on its head, but it does mean there is more to the story than what Darwin proposed. Sexual selection has played a major role in the evolution of elaborate bird song but other selection pressures or processes have also probably played a role, especially at the initial stages of its evolution, the authors note.