Why did our ancestors ditch the shell and start growing babies inside their bodies instead? In this episode of Big Ideas, ...

Q. When we studied high school biology, our teacher said more than 99 percent of animals lay eggs and only a few give live birth. That percentage seems too high. Humans, dogs, cats and cows are ...

Snakes, like most reptiles in the world, are oviparous. This means that rather than producing live young ones, the way mammals do, snakes produce an immature single cell — an egg. Most snakes follow ...

Add Yahoo as a preferred source to see more of our stories on Google. Animals reproduce in a variety of fascinating ways. Some species, including humans and many other mammals, give birth to live ...

Survival in high-altitude regions requires mastering live birth rather than traditional egg laying. The cloaca serves as a single exit point, causing unique complications during birth membrane ...