Probing the deep genetic structure of Africa
Fri, 22 Sep 2023 14:12:44 EDT
Using ancestry decomposition techniques an international research team has revealed a deeply divergent ancestry among admixed populations from the Angolan Namib desert. This unique genetic heritage brings the researchers closer to understanding the distribution of genetic variation in the broader region of southern Africa before the spread of food production.
Dinosaur feathers reveal traces of ancient proteins
Thu, 21 Sep 2023 15:45:21 EDT
Palaeontologists have discovered X-ray evidence of proteins in fossil feathers that sheds new light on feather evolution.
Slow growth in crocodile ancestors pre-dated their semi-aquatic lifestyle
Wed, 20 Sep 2023 11:12:07 EDT
A groundbreaking study is reshaping our understanding of crocodile evolution by pinpointing the onset of slow growth rates to the Late Triassic period, much earlier than the previously assumed Early Jurassic timeline. The research highlights newly discovered fossil crocodile ancestors (known as crocodylomorphs) that exhibited slow growth rates, similar to modern-day crocodilians. Intriguingly, these early crocodylomorphs were not the lethargic, semi-aquatic creatures we are familiar with today; they were small, active, and fully terrestrial. The study also suggests that this slow-growth strategy was not a mere evolutionary quirk but a survival mechanism, as only the slow-growing crocodylomorphs managed to survive the End-Triassic mass extinction. This stands in stark contrast to the fast-growing dinosaurs of the same era, setting the stage for the divergent evolutionary paths that would later define their modern descendants.
Prehistoric fish fills 100 million year gap in evolution of the skull
Wed, 20 Sep 2023 11:03:03 EDT
X-rays of an ancient jawless fish shows earliest-known example of internal cartilage skull, unlike that of any other known vertebrate.
Tiny sea creatures reveal the ancient origins of neurons
Tue, 19 Sep 2023 15:48:32 EDT
A new study sheds new light on the origins of modern brain cells. Researchers find evidence that specialized secretory cells found in placozoans, tiny sea creatures the size of a grain of sand, have many similarities to the neuron, such as the genes required to create a partial synapse. From an evolutionary point of view, early neurons might have started as something like these cells, eventually gaining the ability to create a complete synapse, form axons and dendrites and create ion channels that generate fast electrical signals -- innovations which gave rise to the neuron in more complex animals such as jellyfish. Though the complete story of how the first neuron appeared remains to be told, the study demonstrates that the basic building blocks for our brain cells were forming in the ancestors of placozoans grazing inconspicuously in the shallow seas of Earth around 800 million years ago.