OTAGO DAILY TIMES (New Zealand) 04 March 08 Tuatara evolving rapidly, DNA research reveals
Wellington (NZPA): New Zealand’s living dinosaur, the tuatara, moves slowly but is evolving at a faster rate than a dozen other animals representative of their species, according to recent research.
Evolutionary biologist Prof David Lambert and a team from the Allan Wilson Centre for Molecular Ecology and Evolution have recovered DNA sequences from the bones of ancient tuatara up to 8000 years old.
They found that although tuatara had remained largely physically unchanged over very long periods of evolution, they were 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,’’ Prof Lambert said.
The tuatara rate is significantly faster than for animals including the cave bear, lion, ox and horse.
‘‘Of course, we would have expected that the tuatara, which does everything slowly they grow slowly, reproduce slowly and have a very slow metabolism would have evolved slowly.’’
Prof Lambert said the finding would be helpful in terms of future study and conservation of the tuatara, and the team now hoped 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 too.’’
The tuatara, Sphenodon punctatus, is found only in New Zealand and is the only surviving member of a distinct reptilian order, sphenodontia (Greek for wedge tooth), that lived alongside early dinosaurs and separated from other reptiles 200 million years ago, in the Upper Triassic period
Tuatara evolving rapidly, DNA research reveals