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Ancient DNA Helps Solve the Legend of Giant Eagles
nomrniceguy writes "Gigantic eagles swooping from the skies to rescue Frodo and Sam in the Lord of the Rings may not be just the stuff of legends and fairytales, according to research published in the journal PloS Biology. McMaster University anthropologist Michael Bunce has shed new light on the evolution of the extinct Haast's eagle, the giant bird that once ruled the skies over New Zealand. Weighing between 20 and 30 pounds, the enormous Haast's Eagle dominated its environment. It was 30 to 40 per cent heavier than the largest living bird of prey around today, the Harpy Eagle of Central and South America."
The study didn't prove that large eagles existed. The remains they had did that. All they did was demonstrate that the large eagles were related to much smaller ones, and speciation probably only occurred a million years ago. Comparative genomics is a useful science, but it's not at the point of telling us what an eagle's adult wingspan is yet.
"So its rapid increase in size appears to be a case of island gigantisism."
I suspect this might be the result of natural selection, bringing about equilibrium with the most abundant (and outsized) prey.
"I wonder if the number of flightless species in the area were caused by the presence of this predator in the air?"
A fascinating question, that. Another case of natural selection at work? OTOH, among modern species, not many raptors take prey from the air, although it can/does happen. Most prey is taken from the ground, among larger raptors, at least. So, I guess it would depend on the Haast's eagle's hunting method, which itself likely evolved with its prey.
I love this kind of stuff. It's like a game, a puzzle in retrospect.
Ignorance is curable, stupid is forever.
No, the news is an eagle arrived in New Zealand and increased in weight by 10 to 15 times over [a million years], which is very fast in evolutionary terms. Such rapid size change is unprecedented in birds and animals.