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 ...

Animals reproduce in a variety of fascinating ways. Some species, including humans and many other mammals, give birth to live ...

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 ...

European cuckoos lay very different eggs depending on the host species. Genetic analyses have revealed how this adaptation is inherited without leading to speciation. Bright blue, white, greenish, ...

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

Female lineages of European cuckoos lay eggs with colorful shells and intricate patterns specialized to deceive more than 100 avian hosts into fostering their chicks. Parasitic cuckoo eggshells show ...