Washington, March 21 : Evolutionary biologists at the Allan Wilson Centre for Molecular Ecology and Evolution say that they have recovered about 8000 years old DNA sequences from the bones of ancient tuatara, New Zealand's "living dinosaur".
Professor David Lambert, ancient DNA expert who led the research team, says that tuatara might have remained largely physically unchanged over very long periods of evolution, but they are evolving, at a DNA level, faster than any other animal yet examined.
"What we found is that the tuatara has the highest molecular evolutionary rate that anyone has measured," Professor Lambert wrote in his research paper, which will be published in the journal Trends in Genetics.
He says that the rate of evolution for Adelie penguins, whom he and his colleagues have studied in Antarctic for many years, is slightly slower than that of the tuatara.
Professor Lambert says that the rate of evolution for the tuatara is significantly faster than that for animals including the cave bear, lion, ox and horse.
The researcher, known to be a pioneer of molecular evolution, believes that the findings of his study may be beneficial in terms of conservation of the tuatara.
Professor Lambert and his colleagues are now planning to extend the work to look at the evolution of other animal species.
"We want to go on and measure the rate of molecular evolution for humans, as well as doing more work with moa and Antarctic fish to see if rates of DNA change are uncoupled in these species. There are human mummies in the Andes and some very good samples in Siberia where we have some collaborators, so we are hopeful we will be able to measure the rate of human evolution in these animals too," he says.
The tuatara, Sphendon punctatus, is the only surviving member of a distinct reptilian order Sphehodontia that lived alongside early dinosaurs, and separated from other reptiles 200 million years ago in the Upper Triassic period.