Extinct ‘monkey lemur’ shows similarities to fossil humans

Analysis of teeth of extinct lemurs has revealed fascinating clues to the evolution of humans, a University of Otago study has found. monkey lemur, Archaeolemur, had novel anatomical features not seen in living lemurs, such as lacking a ‘tooth comb’ in the front of the mouth for grooming. The study, published in the American Journal of Biological Anthropology, aimed to assess the diet of Archaeolemur by analysing chipping in 447 teeth, comparing chipping frequencies to those of other primates. The results were surprising — with these remarkable extinct lemurs with dentitions resembling baboons in shape; but presenting tooth chipping patterns similar to fossil hominins such as Neanderthals.

— source University of Otago | Dec 12, 2022

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How Humans’ Ability to Digest Milk Evolved from Famine and Disease

The dawn of dairy farming in Europe occurred thousands of years before most people evolved the ability to drink milk as adults without becoming ill. Now researchers think they know why: lactose tolerance was beneficial enough to influence evolution only during occasional episodes of famine and disease, explaining why it took thousands of years for the trait to become widespread1.

The theory — backed up by an analysis of thousands of pottery shards and hundreds of ancient human genomes as well as sophisticated modelling — explains how the ability to digest milk became so common in modern Europeans, despite being almost non-existent in early dairy farmers. This ability, known as lactase persistence, comes from an enzyme that breaks down milk sugar and usually shuts down after young children are weaned.

The study, published in Nature on 27 July, is the first major effort to quantify the forces that have shaped this trait, says Shevan Wilkin, a molecular archaeologist at the University of Zurich, Switzerland. “Lactase-persistence evolution was much more complicated than we ever thought.”

— source scientificamerican.com | Ewen Callaway | Jul 28, 2022

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Did Darwinian evolution begin before life itself?

A study done by physicists demonstrates that fundamental characteristics of polymeric molecules, such as their subunit composition, are sufficient to trigger selection processes in a plausible prebiotic setting.

Before life emerged on Earth, many physicochemical processes on our planet were highly chaotic. A plethora of small compounds, and polymers of varying lengths, made up of subunits (such as the bases found in DNA and RNA), were present in every conceivable combination. Before life-like chemical processes could emerge, the level of chaos in these systems had to be reduced. In a new study, LMU physicists led by Dieter Braun show that basic features of simple polymers, together with certain aspects of the prebiotic environment, can give rise to selection processes that reduce disorder.

In previous publications, Braun’s research group explored how spatial order could

— source Ludwig-Maximilians-Universität München | Feb 19, 2021

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Ancient skeletal hand could reveal evolutionary secrets

Evolutionary expert Charles Darwin and others recognized a close evolutionary relationship between humans, chimps and gorillas based on their shared anatomies, raising some big questions: how are humans related to other primates, and exactly how did early humans move around? Research by a Texas A&M University professor may provide some answers.

Thomas Cody Prang, assistant professor of anthropology, and colleagues examined the skeletal remains of Ardipithecus ramidus (“Ardi”), dated to 4.4 million years old and found in Ethiopia. One of Ardi’s hands was exceptionally well-preserved.

The researchers compared the shape of Ardi’s hand to hundreds of other hand specimens representing recent humans, apes and monkeys (measured from bones in museum collections around the world) to make comparisons about the kind of locomotor behavior used by the earliest hominins (fossil human relatives).

— source Texas A&M University | Feb 25, 2021

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Neanderthal and early modern human stone tool culture co-existed for over 100,000 years

Research from the University of Kent’s School of Anthropology and Conservation has discovered that one of the earliest stone tool cultures, known as the Acheulean, likely persisted for tens of thousands of years longer than previously thought.

The Acheulean was estimated to have died out around 200,000 years ago but the new findings suggest it may have persisted for much longer, creating over 100,000 years of overlap with more advanced technologies produced by Neanderthals and early modern humans.

The research team, led by Dr Alastair Key (Kent) alongside Dr David Roberts (Kent) and Dr Ivan Jaric (Biology Centre of the Czech Academy of Sciences), made the discovery whilst studying stone tool records from different regions across the world. Using statistical techniques new to archaeological science, the archaeologists and conservation experts were able to reconstruct the end of the Acheulean period and re-map the archaeological record.

Previously, a more rapid shift between the earlier Acheulean stone tool designs often

— source University of Kent | Mar 1, 2021

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Compassion helped Neanderthals to survive

They have an unwarranted image as brutish and uncaring, but new research has revealed just how knowledgeable and effective Neanderthal healthcare was.

The study, by the University of York, reveals that Neanderthal healthcare was uncalculated and highly effective — challenging our notions that they were brutish compared to modern humans.

The researchers argue that the care provided was widespread and should be seen as a “compassionate and knowledgeable response to injury and illness.”

It is well known that Neanderthals sometimes provided care for the injured, but new analysis by the team at York suggest they were genuinely caring of their peers, regardless of the level of illness or injury, rather than helping others out of self-interest.

Lead author, Dr Penny Spikins, senior lecturer in the Archaeology of Human Origin at the University of York, said: “Our findings suggest Neanderthals didn’t think in terms of

— source University of York | Mar 13, 2018

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Organic molecules found in 3.5 billion-year-old rocks

A research team from the University of Cologne has detected organic molecules and gases trapped in 3.5 billion-year-old rocks. the scientists examined about 3.5 billion-year-old barites from the Dresser Formation in Western Australia. The barite thus dates from a time when early life developed on Earth. In the fluid inclusions, the team identified organic compounds such as acetic acid and methanethiol, in addition to gases such as carbon dioxide and hydrogen sulfide. These compounds may have been important substrates for metabolic processes of early microbial life.

— source University of Cologne | Feb 18, 2021

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Modern humans interbred with Denisovans twice in history

Modern humans co-existed and interbred not only with Neanderthals, but also with another species of archaic humans, the mysterious Denisovans. While developing a new genome-analysis method for comparing whole genomes between modern human and Denisovan populations, researchers unexpectedly discovered two distinct episodes of Denisovan genetic intermixing, or admixing, between the two. This suggests a more diverse genetic history than previously thought between the Denisovans and modern humans.

— source sciencedaily.com | Mar 15, 2018

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Genetic rewiring behind spectacular evolutionary explosion in East Africa

Genetic rewiring could have driven an evolutionary explosion in the shapes, sizes and adaptations of cichlid fish, in East Africa’s answer to Darwin’s Galapagos finches.

Published in BMC Genome Biology, an Earlham Institute (EI) study, with collaborators at the University of East Anglia (UEA) and Wisconsin Institute for Discovery, shows that ‘genetic rewiring’ at non-coding regions — rather than mutations to protein-coding regions of genes — may play an important role in how cichlid fish are able to rapidly adapt to fill a staggeringly wide range of environmental niches in the East African Rift lakes.

The results could help future studies to improve breeding of economically important cichlid species such as tilapia — a staple in aquaculture.

Darwin’s famous finches are one of the most well-known examples of evolution by natural selection, and specifically adaptive radiation. The birds he observed on the Galapagos archipelago had differences in their beaks that could be matched to fit their specific feeding habits — whether they ate big or small seeds, insects, or even used tools to find food.

Amazingly, in the 2-3 million years it took 14 species of finch to evolve on the Galapagos Islands,

— source Earlham Institute | Jan 19, 2021

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The ABCs of species evolution

A transporter protein that regulates cell membrane cholesterol likely played an important role in vertebrate evolution, according to a review published by iCeMS researchers in the journal FEBS Letters.

Almost four decades of research have led scientists at Japan’s Institute for Integrated Cell-Material Sciences (iCeMS) to propose that a family of transporter proteins has played an important role in species evolution. One protein in particular, called ABCA1, was likely crucial for vertebrate evolution by helping regulate when signals involved in cell proliferation, differentiation and migration enter a cell. This process was necessary for vertebrates to develop into more complex organisms with sophisticated body structures.

The ATP-binding cassette proteins (ABC) are very similar across species, including in bacteria, plants and animals. There are different types of ABC proteins with different transportation roles, importing nutrients into cells, exporting toxic compounds outside them, and regulating lipid concentrations within cell membranes.

ABC proteins must have played important roles in evolution. By transporting lipids, they enabled plants and animals to thrive on land by protecting them from water loss and pathogen infection. They

— source Kyoto University | Dec 23, 2020

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