Have you ever noticed how some baby animals, like newborn horse foals, are able to walk and even run a few hours after birth, while others, like baby robins (and baby humans) are helpless for so long? Animals that are born fully developed and able to take care of themselves are called precocial, while animals that are born weak and rely on their parents for everything are called altricial.
Being born ready to run (or even fly, in the case of some birds) within a few hours is helpful for animals that need to be able to escape from predators. For example, blue wildebeests are able to stand within six minutes of being born, and within a day are able to outrun hyenas. But for other animals, it pays off to grow more slowly and rely on parents for food and protection. There’s even a link between how animals’ brains develop depending on whether they’re precocial or altricial. Precocial animal babies’ brains are big, but they don’t grow that much more as the animal reaches adulthood. Altricial animals start out helpless, but their brains grow and develop so that by the time they’re adults, their brains are comparatively bigger than those of precocial animals.
Photo via Pixabay