Ground Report

A new study has claimed that lack of a heat generating tissue may have fontributed to the extinction of dinosaurs. A team of researchers at New York Medical College cane to the conclusion after discovering why birds, unlike mammals, lack a tissue that is specialised to generate heat, the Science Daily reported. All mammals have two kinds of adipose tissue, white fat and brown fat. White fat is used for storing energy rich fuels, while brown fat generates heat. The ability to produce brown fat evolved in a common ancestor of birds and mammals, but the ability to generate heat was lost in the group that gave rise to birds and lizards after it separated from the mammalian lineage ( the researchers found the lizard genome  similarly lacks a UCP1 gene). ” This strongly implies that dinosaurs, which diverged from bards even later than lizards, also lacked brown fat,” according to the researchers.