Hedges thinks the Barbados snake may be at or near the minimum possible size for snakes, though he cannot say for sure that no smaller species exists -- several other snake species are nearly as small. While it is possible that a smaller species exists, finding such an animal is unlikely. "Snakes may be prevented by natural selection from becoming too small because, below a certain size, there may be nothing for their young to eat," said Hedges, adding that the Barbados snake, like others to which it is related, likely feeds primarily on the larvae of ants and termites.
In contrast to larger species -- some of which can lay up to 100 eggs in a single clutch -- the smallest snakes, and the smallest of other types of animals, usually lay only one egg or give birth to one offspring. Furthermore, the smallest animals have young that are proportionately enormous relative to the adults. For example, the hatchlings of the smallest snakes are one-half the length of an adult, whereas the hatchlings of the largest snakes are only one-tenth the length of an adult. The Barbados snake is no exception to this pattern. It produces a single slender egg that occupies a significant portion of the mother's body.
"If a tiny snake were to have two offspring, each egg could occupy only half the space that is devoted to reproduction within its body. But then each of the two hatchlings would be half the normal size, perhaps too small to function as a snake or in the environment," said Hedges. "The fact that tiny snakes produce only one massive egg -- relative to the size of the mother -- suggests
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