When dinosaurs became extinct, some birds got fat and lost their ability to fly, concludes a new study that helps to explain the existence of modern hefty birds, like ostriches, rheas, kiwis, emus, and cassowaries.
Goodbye...
(Image courtesy of Michael A. Digiorgio)
Hello...
(Credit: heyjude)
The very basic process is that when an animal, or multiple species, die out, others can come in to fill the previously occupied ecological niche. (It makes me wonder what animal(s) would fill the ecosystem void left by humans, should we become extinct.)
Matthew Phillips, an evolutionary biologist at the Australian National University, and his colleagues analyzed DNA for flightless birds, along with other data, to determine how the birds evolved. The study, published in the latest issue of the journal Systematic Biology, found that the ancestors of these birds, palaeognaths, could all fly. These ancient birds then all independently lost this ability around 65 million years ago, just as dinosaurs were going extinct. A coincidence? No.
"Here we suggest a new hypothesis that flying palaeognaths accessed similar novel niche opportunities that became available on different landmasses with the K/T boundary extinction of dinosaurs and in the absence of previously overwhelming predation pressures, independently became flightless," wrote Phillips and his team.
Bizarre things like this can happen when former prey find themselves without predators. I'm reminded of our recent story about dwarf Transylvanian dinosaurs. In that case, large plant-eating dinosaurs wound up marooned on an island and shrunk over time since they had few predators, but also limited food sources.
When dinosaurs kicked the earthly bucket, however, some birds could eat more and move less, only not while being airborne.
Tags: Dinosaurs, Extinct Animals, Feathered Dinosaurs, Late Cretaceous Dinosaurs, Paleontology,
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