Loons are on the mend in Maine, filling more of the state's lakes and ponds with their haunting calls, although conservationists say the birds aren't out of the woods yet. Maine is home to a few thousand of the distinctive black-and-white waterbirds — the East Coast’s largest loon population — and conservationists said efforts to protect them from threats helped grow the population. An annual count of common loons found more adults and chicks this year than last, Maine Audubon said this week.

Today’s wolves and dogs share a common ancestor. But a deeper look at their genes reveals that interbreeding since dogs were domesticated 20,000 years ago hasn’t been as rare as scientists assumed.

The closer to Earth a satellite flies, the clearer a picture it can take of the surface. But low-flying satellites also have to deal with atmospheric drag.