At some point in the past, far distant from this week’s release of the Event Horizon Telescope picture of a gargantuan 55-million-year-old black hole in an ancient elliptical galaxy, a distinct branch of human evolution, the Denisovans, disappeared, but not before interbreeding with modern humans. Today, people in places like East Asia and New Guinea still carry fragments of Denisovan DNA. Over the past decade, the Denisova Cave in a valley in the Altai Mountains of southern Siberia has yielded fossils harboring DNA dating back 200,000 years.
“It’s quite incredible, the extremities, that is the hand and feet bones are remarkably Australopithecine-like. The Australopithecines last walked the earth in Africa about 2 million years ago and are considered to be the ancestors of the Homo group, which includes modern humans,” said Philip Piper with The Australian National University (ANU).
Once upon a time—in the Eocene epoch—whales were quadrupeds. They walked on land. The cetaceans, the group including whales and dolphins, originated in south Asia more than 50 million years ago from a small, four-legged, hoofed ancestor. Now, researchers reporting the discovery of an ancient four-legged whale—found in 42.6-million-year-old marine sediments along the coast of Peru—have new insight into whales’ evolution and their dispersal to other parts of the world.
A third extinct “ghost species” beyond Neanderthals and Denisovans that interbred with anatomically modern humans has been unveiled by researchers from Spain and Estonia using artificial intelligence. This third extinct species is likely a hybrid or close relative of Neanderthals and Denisovans that crossbred with “Out of Africa” modern humans in Asia.
The beginning of the end started with violent shaking that raised giant waves in the waters of an inland sea in what is now North Dakota. Then, tiny glass beads began to fall like birdshot from the heavens. The rain of glass was so heavy it may have set fire to much of the vegetation on land. In the water, fish struggled to breathe as the beads clogged their gills, says paleontologist Robert DePalma about the killing field laid down soon after the asteroid impact that eventually led to the extinction of all ground-dwelling dinosaurs at the end of the Cretaceous Period, the so-called K-T boundary, that exterminated 75 percent of life on Earth.
The mass extinction brought about at the end of the 50-million-year-long Permian period, brought about the end the entire Paleozoic era, in progress since the dawn of animal life. The Paleozoic, with its ancient seas filled with trilobites, brachiopods, and strange reefs, was as starkly different from the age to come as the age of dinosaurs is from our world today.
