SCIENCE

What Color Was That Moa?

July 7, 2009

Moas have been extinct for hundreds of years. The entire family—ten species of flightless birds, some as tall as 12 feet—was wiped out shortly after humans occupied New Zealand around 1280. Now a team of scientists in Australia and New Zealand has painstakingly analyzed 2,500-year-old feather fragments to isolate DNA and reconstruct the appearance of the moas' feathers. What did these enormous, mysterious, lost birds look like? The answer is... they were brown. Three species were, anyway. The fourth one, identified by genetic analysis, was... brown with some white speckles.

This is more exciting than it sounds. Until now, people had recovered DNA from only the base, or calamus, of feathers, where they attach to a bird's body. The new study demonstrates that it's possible to analyze DNA from other fragments of feathers, which is useful because the calamus often breaks off.

For an extinct family, moas and their natural history have gotten a lot of attention lately. They were once the dominant herbivores on New Zealand islands. A recent analysis of their coprolites, or fossilized feces, showed that they ate a lot of low-lying herbs, which was a bit of a surprise for such tall creatures. The plants probably co-evolved with moas, and once the moas went extinct, those plants became much less common. The authors of the new study suggest that the moas' dull colors may have helped them hide from Haast's eagles. (Like moas and 41 percent of New Zealand's birds, the eagles also went extinct in the past few hundred years.) Moas probably weren't subject to the kind of sexual selection that leads to long tails in barn swallows, bright red epaulets on red-winged blackbirds, or spectacular trains (don't call them "tails" or zoologists will snap at you) on peacocks.

Once humans got to New Zealand, moas were pretty much doomed. Like the dodo on Mauritius and the great auk on islands in the North Atlantic, they were big, meaty, flightless and poorly defended. (Big, meaty and flightless aren't such a problem if, like the cassowary, you also have razor-sharp talons and an irritable disposition.)