Call it "ovulation on demand"—a bizarre male bark jump-starts a female cheetah's reproductive system, adding a much-needed boost to breeding the rare big cats in captivity, experts say.With audio.

Scientists are studying bees' aggressive behavior and ocular and navigational skills in hopes of improving missile technology.

The little-known reptile from the Galapagos fills a crucial gap in the evolution of land iguanas, scientists say. But its future may not be as rosy.

Robots became more and more human-like in the past year, which saw the debuts of "emotional" robots, robot bartenders, robot swarms, and more.

In a remote corner of Finland near the Arctic Circle, an international team of elves helps Santa respond to hundreds of thousands of letters from children around the world.

Spectacular displays of Christmas lights draw thousands of spectators in Sydney, Australia.

Some of the inhabitants of the Sydney Zoo were as eager to unwrap their presents as their human counterparts.

A simple sandwich bag can bring new hope to the parents of premature babies.

New insights into the animals intimate encounters include species that cut holes into their partners for sex, squid that swap genders, and males that deploy flesh-burrowing sperm.

Miniature statues of President-elect Barack Obama and his wife, Michelle, have gone on sale in Naples for use in Christmas nativity scenes.

A zoo orangutan that learned to whistle could offer clues about the origins of human speech.

Bizarre prehistoric creatures--sea monsters, gargantuan rodents, a redheaded Neanderthal--are among the stars of the most read stories on dinosaurs and fossils by National Geographic News in 2008.

Researchers in Austria say they've found that dogs react negatively to perceived unfair treatment.

See National Geographic News's most popular individual photos of 2008, including pictures of a giant stingray, a "smiling" sky, a lizard-snake standoff, and more.

Recently found fossils reveal that an ancient amphibian swung its head and upper jaw upwards to eat in an action much like raising a toilet seat.