Gerald Mayr—AP By Associated Press 8:04 AM EST (NEW YORK) — Fossils from New Zealand have …
The biggest penguin today, the emperor in Antarctica, stands less than 4 feet (1.2 meters) tall.
Mayr and others describe the giant creature in a
paper released Tuesday by the journal Nature Communications. They named
it Kumimanu biceae, which refers to Maori words for a large mythological
monster and a bird, and the mother of one of the study’s authors. The
fossils are 56 million to 60 million years old.
That’s nearly as old as the very earliest known
penguin fossils, which were much smaller, said Daniel Ksepka, curator at
the Bruce Museum of Greenwich, Connecticut. He has studied New Zealand
fossil penguins but didn’t participate in the new study.
The new discovery shows penguins “got big very
rapidly” after the mass extinction of 66 million years ago that’s best
known for killing off the dinosaurs, he wrote in an email.
That event played a big role in penguin history.
Beforehand, a non-flying seabird would be threatened by big marine
reptile predators, which also would compete with the birds for food. But
once the extinction wiped out those reptiles, the ability to fly was
not so crucial, opening the door for penguins to appear.
Birds often evolve toward larger sizes after they
lose the ability to fly, Mayr said. In fact, the new paper concludes
that big size appeared more than once within the penguin family tree.
What happened to the giants?
Mayr said researchers believe they died out when
large marine mammals like toothed whales and seals showed up and
provided competition for safe breeding places and food. The newcomers
may also have hunted the big penguins, he said.
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