Why do so many baby animals have spots?

The animal kingdom is dotted with species that give birth to spotted young, from deer and cheetahs to birds and fish. Even species that we don’t typically associate with spots, such as lions, wear the pattern as babies, only to lose it later in life.

But what purpose do these spots serve, and why do only some species seem to have them?

While no systematic study has traced the evolutionary origin of spotted baby animals, Kiyoko Gotanda, an evolutionary biologist at Brock University in Ontario, said it is likely so prevalent because it functions as excellent camouflage. Because spots are useful in keeping babies hidden from predators, they’ve evolved multiple times in a phenomenon known as convergent evolution, in which several lineages evolve similar features without sharing a common ancestor.

“Clearly, there’s strong selection for protection of babies,” Gotanda said. “If preventing them from being seen through spotting is one of the mechanisms, it’s intuitive that it would have evolved in multiple taxa.”