Scars on the jaw of a 120 million year old marine reptile suggest that life might not have been easy in the ancient polar oceans. The healed bite wounds were probably made by a member of the same species. Such injuries give important clues about the social behaviour of extinct sea creatures from the time of dinosaurs. The find is described in a forthcoming issue of Acta Palaeontologica Polonica.

Scientists have discovered a new component of mitochondria that plays a key part in their function. The discovery, which is presented in the journal Cell Metabolism, is of potential significance to our understanding of both inherited and age-related diseases.

New findings from University of Utah School of Medicine researchers show that the retrovirus called XMRV is not present in the blood of patients who have chronic fatigue syndrome (CFS). These findings contradict a widely reported 2009 Science study that linked CFS to XMRV.

Over 100 million years ago, the understory of late Mesozoic forests was dominated by a diverse group of plants of the class Equisetopsida. Today, only one genus from this group, Equisetum (also known as horsetail or scouring rush), exists—and it is a prime candidate for being the oldest extant genus of land plant.