Genome Analysis Show how The Tibetan Ground Tit Survives the Harsh Environment

The ground tit (Parus humilis), lives in the Tibetan plateau, a harsh place for a little bird. Yet, the bird has perfectly adapted to life on the world's highest plateau. A new study shows how the genetic make-up of the bird is helps it deal with environment.

Previously it was believed that the Tibetan ground tit is a corvid (belonging to crow family) but only recently, researchers found that the bird is the world's largest tit. The present study confirms this fact. Researchers found that the ancestor of the ground tit split from other tits somewhere between 7.7 and 9.9 million years ago. The study also shows how this bird can live in low oxygen conditions.

"We have long known that these birds are well adapted to living with low oxygen levels, typical of high elevation, but until now we have had only a limited understanding of the genetic background of these adaptations," Dr Sankar Subramanian, from Griffith University's Environmental Futures Centre, who took part in the study, said in a news release.

The bird is different from other birds that live on trees; one it stays on ground, foraging and digging tunnels to build nests and second, it looks different from other birds with longer legs and larger body size.

One major survival strategy of the bird is that it can select genes that are associated with hypoxia response and skeletal development, just like other animals found in high altitudes of Tibet and Andes, Dr Subramanian said. Also, the bird has higher expression of fat burning genes that help it withstand the cold environment.

Tibetan ground tits rarely appear at altitudes below 3,000 meters above sea level and never in places where there are many trees. The bird also rarely flies, preferring to hop or jump to get around.

The bird also has a reduced response to bacteria and viruses probably because there are very few bacteria that live up there. Another weakness is the reduced ability of smell in these birds, which again is probably due to arid atmosphere of the region.

The bird is current deemed as Least Threatened by the International Union for Conservation of Nature (IUCN) Red List.

The study, "Ground tit genome reveals avian adaptation to living at high altitudes in the Tibetan plateau" in the journal Nature Communications.