Paleontology

Blogs about paleontology

A diagram indicating the hominins that have left genetic traces in the DNA of modern humans.

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An article published in the journal “Science” reports the discovery of genes belonging to two previously unknown hominin species in the DNA of modern humans. A team of researchers led by the University of California, Berkeley used a new algorithm called TRACE (TRacking Archaic Contributions via ARG Estimation), which they developed to reconstruct genetic relationships among hundreds of living human genomes. This allowed them to recognize two archaic genetic components from hominins that interbred with Homo sapiens in Africa over 50,000 years ago, and another from an interbreeding that occurred approximately 1.8 million years ago. The super-archaic genes of the second group don’t derive from a different interbreeding with modern humans, but from an interbreeding with the Denisovans.

Illustration by artist Peter Trusler depicting the interaction between an ichthyosaur, a pterosaur, and a pliosaur. (Image courtesy Peter Trusler)

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An article published in the journal “Gondwana Research” reports the discovery of an ichthyosaur fossil in present-day Australia that preserved the contents of its stomach, which includes the remains of a pterosaur. The ichthyosaur itself shows remarkable signs of having been bitten by a pliosaur, which literally broke its bones. A team of researchers led by Dr. Matt White of the University of New England studied these fossils and reconstructed this snapshot of the ecosystem in which these animals lived during the Cretaceous Period. The result reveals a portion of the food chain that existed in that area approximately 100 million years ago.

A photo and a drawing of the holotype of Zhengheornis buyu.

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An article published in the journal “Science Advances” reports the identification of a bird that lived approximately 150 million years ago, during the Jurassic period, and shows a step in the evolution from the tail type typical of dinosaurs to that of birds, equipped with a so-called pygostyle. A team of researchers led by Wang Min of the Chinese Academy of Sciences, who named it Zhengheornis buyu, studied a fossil discovered in 2024 that has a tail with 15 vertebrae, while early bird relatives had tails with over 30 vertebrae.

Holotype of Tylosaurus rex, at the Perot Museum of Nature and Science, Texas (Photo Gary Todd)

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An article published in the “Bulletin of the American Museum of Natural History” reports the identification of a new species of mosasaur, named Tylosaurus rex because its characteristics indicate it was a massive and fierce predator. A team of researchers reexamined Tylosaurus fossils previously attributed to other species of this taxonomic genus of mosasaurs, concluding that some specimens had anatomical characteristics different enough to warrant assignment to a new species.

The skull, ulna, and femur of a chimpanzee (A), Sahelanthropus tchadensis (B), and Homo sapiens (C)

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An article published in the journal “Science Advances” reports the results of a study concluding that Sahelanthropus tchadensis was capable of walking on two legs approximately 7 million years ago. A team of researchers examined available fossils of this early hominin, using analyses that included 3D modeling, concluding that its species had many ape-like characteristics with some adaptations for bipedalism.