New study sheds light on mammals' early evolution

This image provided by the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) under the Chinese Academy of Sciences shows the Jurassic mammal fossils discovered in north China's Inner Mongolia Autonomous Region. (IVPP/Handout via Xinhua)

A study led by Chinese scientists on Jurassic mammals has shed light on the early evolution of mammals, according to the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) under the Chinese Academy of Sciences.

There are two important morphological and functional changes in the evolution from reptiles to mammals, one is the transformation of teeth from simple to complex to improve feeding capacity, the other is the transformation of the mandibular skull joint into middle ear ossicular combination to improve auditory effectiveness.

An international research team led by the IVPP studied Jurassic mammal fossils from north China's Inner Mongolia Autonomous Region and southwest China's Yunnan Province, had revealed the earliest evolution of tooth, middle ear and jaw joint in mammals.

The study provides a complete chain of evidence for the evolution of the mammalian middle ear, a world puzzle, said Mao Fangyuan with the IVPP.

The results were recently published in two papers in the journal Nature.