Very fast
2005/03/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria
In New Zealand are the bones of a giant eagle. They are bones about two thousand years ago, of a recently disappeared species, the eagle of Haast. Given the size of the bones, the eagle was a bird of about 14 kilos, much larger than the largest eagle of today.
Such a large bird is thought to be the evolution of another large bird. But in the analysis of mitochondrial DNA nothing similar has been found. In fact, from a genetic point of view, the eagles closest to the Haast eagle are very small. Moreover, this giant New Zealand eagle was the evolution of another ten times smaller, descended from an ancestor a million years ago.
Such a change in size in evolution is not usual. Few examples are known: The iguanas of the Galapagos Islands, for example. But no other examples are known in birds.
