Birds that bury their eggs: How megapodes’ nesting behavior evolved

Australian Brush-turkey chick shortly after hatching and emerging
from incubation mound and showing well-developed flight feathers.
Photo: Burke Museum.

By Sharon Birks

Did you know that not all birds sit on their eggs to incubate them? Megapodes (family Megapodiidae)—a fascinating group of birds named for their large feet—cleverly harness environmental heat sources to incubate their eggs.

Depending on the species and location, megapodes may lay their eggs in burrows dug in sun-warmed beaches or geothermally active areas, or they may build large incubation mounds that function like compost piles and generate heat through decomposition.

Although most megapodes look like distant chicken relatives (they are), their unique incubation behavior has driven a suite of unusual adaptations, including:

• large feet to help them dig burrows or build mounds; 
• thin, porous egg shells to help eggs “breathe” underground; and
• the ability for chicks to dig themselves out from under several feet of soil after hatching and emerge ready to fly and fend for themselves.

How did this odd incubation behavior evolve?

Tracked at the molecular level: Wolverines return to the North Cascades



Logan was live-captured for the first time on January 24, 2013
near Easy Pass. (Photo by U.S. Forest Service).

Wolverines are one of the rarest and most elusive mammals in North America. After being hunted to extinction in Washington state in the 1930s, they’re finally starting to return to the northern Cascade Range.

Keith Aubry, research wildlife biologist with the U.S. Forest Service Pacific Northwest Research Station, has led a study to track wolverines found in Washington since 2006. Each winter, he and his team carefully live-capture wolverines, like “Logan,” the young male in the photograph to the right, to document their appearance, sex, age, and condition.