A complete Mixodectes pungens skeleton reveals it was a leaf-eating, tree-dwelling mammal closely related to primates and colugos, refining its evolutionary position after over a century of mystery. For...

New fossil evidence suggests echidnas evolved from a water-dwelling ancestor, not a land-based one. The bone structure closely resembles that of semi-aquatic animals like the platypus. A tiny fossilized...

The sprawling-upright transition across mammal evolution, showing changes in posture and limb bone shape. Credit: Magdalen Mercado, from Brocklehurst RJ, et al., 2025, PLOS Biology, CC-BY 4.0 Early mammal...

Researchers have precisely dated key fossil sites in Central Anatolia, Türkiye, to 7-10 million years ago using a new Argon-Argon method, shedding light on mammalian and primate evolution in this critical...

Small fossils show mammals moved to the ground before the dinosaurs vanished. New plants changed habitats, giving better food and shelter.

Fossil Rewrites Cretaceous Mammal Evolution Story

A groundbreaking study published in Frontiers in Mammal Science reveals that a 236-million-year-old cynodont fossil, Chiniquodon theotonicus, provides the first fossil evidence that some mammal ancestors gave birth to live young rather than laying eggs. This discovery pushes the timeline of live birth evolution back by up to 95 million years. Researchers analyzed bone microstructure and neonatal growth lines in the fossil, comparing it to modern placental mammals. The findings suggest that traits like lactation and brain size, previously thought to be unique to mammals, may have evolved in cynodonts. The study challenges the long-held belief that cynodonts, the predecessors of modern mammals, laid eggs, offering new insights into the evolutionary transition from egg-laying to live birth. The research highlights how embryonic tissues in fossils can reveal reproductive strategies, potentially reshaping understanding of mammalian origins. Future studies aim to find more evidence of live birth in other cynodont species, further clarifying the genetic and evolutionary basis of mammalian reproduction.

Understanding how mammals remember extinction may help humanity navigate the next environmental crossroads

Millions of years before the asteroid impact that ended the reign of the dinosaurs, mammals were already beginning to shift from tree-dwelling to ground-based lifestyles. A groundbreaking study uncovered...

During the age of dinosaurs, early mammals probably lacked the stripes and spots of their modern relatives, having uniformly dark, drab coats.