Friend or foe? A California two-spot octopus (Octopus bimaculoides) gives observers the eye at the Marine Biological Laboratory in Woods Hole, Mass.
Tom Kleindinst/Marine Biological Laboratory
The clicker became a popular tool for dog training in the 1980s. Today, it has also caught on with humans — helping people to become better dancers, fishermen, golfers, and now, surgeons.
An American black bear (they are often brown) is seen in Yosemite National Park. Rangers hope tracking the bears' locations will help prevent the animals from being hit by cars.
Yosemite National Park via AP
New research confirms that wild chimpanzee mothers play a key role in the "home schooling" of their offspring, including lessons on the use of specialized tools to fish for a meal in the termite hills of Nouabalé-Ndoki National Park.
Courtesy of Michael Nichols
For 15 years, biologists in single-person, ultralight aircraft would each lead an experimental flock of young whooping cranes from Wisconsin to a winter home in Florida. But not anymore.
The dark red color and looming posture of this Octopus tetricus likely signals menace to another octopus nearby, say scientists who studied 186 octopus interactions in 52 hours of underwater video.
David Scheel/Current Biology
Lily chases sheep for the first time in her shepherd-mix life, at Raspberry Ridge Sheep Farm in eastern Pennsylvania. Several times a year the farm invites dogs for "herding instinct tests."