Penguin DNA Evolving Faster Than Thought

sakura times
By Carla Valenzuela

Investigations have showed that the evolution of penguins happens in double time, according to new genetic calculations.
A team of researches collected mitochondrial DNA from Adelie penguins currently living in Antarctica and from bones of penguins that had lived in the same place as long as 44,000 years ago. The analysis revealed that penguins are evolving on a molecular scale two times faster than standard calculations.
Using an ancient DNA allowed the researchers to see all the changes in the mitochondrial genome, a process that is invisible when one compares DNA between two modern species. Each difference in the DNA between two species is calculated as a single change, when in fact multiple changes might have happened. The researchers were able to see all of these changes by comparing the modern birds to several generations of their ancestors.The whole mitochondrial genome has more changes per unit time than previous methods had predicted. The researchers found protein coding genes change more slowly than the hypervatiable region and genes that encode transfer RNAs and ribosomal RNAs change even more slowly than protein coding regions. This data indicate that scientist should calculate evolutionary rates on the basis of the entire mitochondrial genome and not just from a small part