Tuataras might take a century before having sex but scientists have declared New Zealand's living dinosaur to be the world's fastest evolving animal.
Although tuatara have remained largely physically unchanged during very long periods of evolution, the researchers found the animals are evolving at a DNA level faster than any other animal.
The discovery, reported in the international journal Trends in Genetics, was made by scientists at Massey University's Allan Wilson Center for Molecular Ecology and Evolution in Auckland.
They have taken DNA sequences from the bones of ancient tuatara up to 8,000 years old.
They reported the tuatara has the highest molecular evolutionary measured, changing than any other animal, including bears, lions, ox and horses.
Research found the tuatara is evolving at an average rate of 1.56 substitutions per nucleotide per million years.
This measurement puts it above the previous fast-evolving record holder, the Adelie penguin.
The paper was authored by Massey's Professor David Lambert and researchers Jennifer Hay, Sankar Subramanian, Craig Millar and Elmira Mohandesan.
They have measured the evolution rates of various species, and plan to extend their work to humans, sampling DNA from human mummies from the Andes and Siberia.
Earlier this month a tuatara at the Southland Museum and Art Gallery won international headlines by having his first sex at the age of 111.
- Fairfax Media