JEHOLBAATAR KIELANAE

About:

• The study, published in the journal Nature, looked at fossils of the extinct rodent-like mammal — Jeholbaatar kielanae — at Jehol Biota of China, and noted that these animals had a middle ear that is distinct from those of its relatives.
  
  
• The fossil clues provide solid evidence of the morphology and formation of the inner ear bones, which are fully detached from the lower jaw. The new fossil reveals a transitional stage in the evolution of the surangular — a “reptilian” jawbone.
  
  
• In these extinct mammals, the evolution of the middle ear may have probably been triggered by functional constraints on the bones and muscles involved in feeding.
  
  
• This advance may lead to better understanding of the evolution of hearing.