When you think of animals that lay eggs, birds are probably the first to come to mind. But nature is far more diverse than that. Egg-laying is one of the oldest and most widespread ways of ...

Even within the world of egg-laying animals, there is an incredible variety of reproductive strategies. Some species mate before the female lays her eggs, ensuring they are fertilized internally, ...

Eggs helped animals conquer land—but most mammals stopped laying them. Why is that? Why do most animals lay eggs, while humans and most mammals give birth to live young? In this episode of Big Ideas ...

Birds may be the most famous egg-layers, but they’re far from the only ones! Across the animal kingdom, reptiles, amphibians, fish, and even a few rare mammals rely on this ancient method of ...