How do mammals and birds maintain their body temperature?

Researchers at Ben-Gurion University of the Negev have found the mutations that may explain the phenomenon

Researchers from Ben-Gurion University of the Negev determined, for the first time, what are the most likely genetic mutations to explain how mammals and birds became warm-blooded. The research findings were recently published In the journal Nature Ecology & Evolution.

The researchers looked for the functional mutations (changes with an effect in the genome) that reappeared independently during evolution and are therefore the best candidates to explain the independent evolution of traits in unrelated groups of species. This process is a well-known phenomenon in evolution called "convergent evolution" (like the development of wings in bats and birds), but it lacks a satisfactory molecular explanation.

The researchers identified for the first time the complete collection of such "convergent" mutations during the evolution of reptiles, birds and mammals (300 million years of evolution). They then took the research a step further, wondering if these mutations could explain a well-known event of convergent evolution. After they discovered that most convergent mutations appeared independently in birds and mammals, they asked themselves what trait arose independently in these two species, and immediately checked whether it was a trait of maintaining body temperature.

Indeed, genes involved in maintaining body temperature have acquired the same mutations (independently) among birds and mammals. This is the first time that a molecular explanation has been given for this evolutionary phenomenon.

Prof. Dan Meshmer from the Department of Life Sciences at the university, together with student Liron Levin, conducted the first analysis of 300 million years of evolution and discovered the molecular basis for the development of warm-blooded animals.

Prof. Meshmer is the head of the Center for Genomics and Evolutionary Medicine at Ben-Gurion University of the Negev.

The research was funded by research funds of the Israel Science Foundation, the Binational Science Foundation and a grant from the Department of Life Sciences of the United States Army.