DNA from fossilised eggshells could help reconstruct lives of extinct birds
Scientists have collected DNA from the fossilised eggshells of birds that died hundreds and in some cases thousands of years ago.
The oldest eggshell to yield DNA came from an Australian emu that died around 19,000 years ago. It is the first time that scientists have succeeded in extracting ancient DNA from the fossilised eggshells of a bird.
Genetic material from the Madagascan elephant bird, the heaviest bird that ever lived, was also recovered, along with DNA from Australian owls, New Zealand ducks and flightless moas.
Elephant birds were native to Madagascar but had gone extinct by the 17th century. The ostrich-like creatures grew to around 3 metres tall and weighed up to half a tonne. Their eggs were bigger than footballs.
Eggshells from two other extinct species, the little bush moa and the heavy footed moa, both from New Zealand's north island, were estimated to be more than 3,000 years old. Attempts to collect DNA from a 50,000-year-old flightless Australian bird from the genus Genyornis failed because the DNA had degraded too much.
The ancient DNA has yet to be sequenced, but researchers will soon be looking to draw up genetic profiles of long-lost birds by extracting genetic material from eggshells held in museums and excavated at archaeological and fossil sites.
Previously, they had little hope of reading DNA from species that lived in warm climates because the genetic material breaks down so quickly.
By sequencing the genomes of ancient birds, scientists hope to build up a better picture of their physiology and how they dispersed and split into different species. It may even be possible to surmise their diets from genes encoding the enzymes for digesting particular types of food.