Kiwi bird genome sequenced
The kiwi, national symbol of New Zealand, gives insights into the evolution of nocturnal animals. Its unusual biological characteristics make the flightless kiwi a unique kind of bird. Kiwi have a number of features that make them interesting for study: They only have rudimentary wings, no tail and a very long beak with nostrils. They are mainly nocturnal with a low basal metabolic rate and the lowest body temperature among birds. To date there has been little genetic information available for this species that might help scientists to understand their unusual biology better.
An international team led by Torsten Schöneberg of the Institute of Biochemistry of the Medical Faculty at the University of Leipzig and Janet Kelso of the Max Planck Institute for Evolutionary Anthropology have now sequenced the genome of the brown kiwi (Apteryx mantelli). Their analyses show genetic changes that likely reflect adaptation to nocturnal life. Although mutations have inactivated some of the key genes involved in color vision, the number of odorant receptor genes is expanded suggesting that the kiwi sense of smell is highly developed. These changes happened about 35 million years ago which is after the kiwi’s arrival in New Zealand.
“Already French botanist and zoologist Jean Baptiste de Lamarck, who lived in the 18th century, hypothesized that evolution works in accordance with a ‘use it or lose it’ principle. It is therefore very likely that the kiwi lost its color vision since this was no longer needed for its new nocturnal lifestyle”, says first author Diana Le Duc, MD, at the University of Leipzig. “The kiwi’s sense of smell – which was required for foraging in the dark of the night – became more acute and the repertoire of odorant receptors increased adapting to a wider diversity of smells.”
DNA analyses of two kiwi individuals show, however, that according to first estimates there is little genetic variability in the population. This could further endanger the survival of this species and will have to be taken into account when planning future breeding programs. “The genome of the kiwi is an important resource for future comparative analyses with other extinct and living flightless birds”, says computational biologist Janet Kelso of the Max Planck Institute for Evolutionary Anthropology.
Original publication
Original publication
Le Duc D., Renaud G., Krishnan A., Sällman Almén M., Huynen L., Prohaska S.J., Ongyerth M., Bitarello B.D., Schiöth H.B., Hofreiter M., Stadler P.F., Prüfer K., Lambert D., Kelso J., Schöneberg T.; "Kiwi genome provides insights into evolution of a nocturnal lifestyle"; Genome Biology, 2015.
Organizations
Other news from the department science
Get the analytics and lab tech industry in your inbox
From now on, don't miss a thing: Our newsletter for analytics and lab technology brings you up to date every Tuesday. The latest industry news, product highlights and innovations - compact and easy to understand in your inbox. Researched by us so you don't have to.