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Researchers say they have found the world’s smallest snake on the Caribbean island of Barbados. Evolutionary biologist Blair Hedges says that the tiny reptile, which can comfortably curl up on a quarter and which is barely as wide as a spaghetti noodle, may also be at the evolutionary limit for the smallest size possible for snakes.

Most snakes produce clusters of eggs, but the newly discovered species lays only one egg, which hatches a youngster who is one-half the length of the adult. That would be like humans giving birth to a 60-pound (27kg) baby. Dr Hedges added that the snake’s size might limit the size of its clutch. “If a tiny snake were to have more than one offspring, each egg would have to share the same space occupied by the one egg and so the two hatchlings would be half the normal size.” The hatchlings might then be too small to find anything small enough to eat [BBC News].

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By examining the genetics of snake embryos, researchers have solved a long-standing evolutionary mystery regarding the evolution of fangs on venomous snakes. Researchers have been puzzled because the fangs, which are syringe-like teeth that draw poison from venom glands, have very different placement in different species. Most venomous snakes, including grass snakes, have fangs positioned in the rear of the mouth, while a few groups, including rattlesnakes, cobras and vipers, have fangs jutting down from their upper jaws in the front of the mouth [LiveScience].

Adding to the confusion, researchers had found that the front-fanged snakes aren’t closely related to each other, suggesting that the front-fang trait evolved at least two separate times. The assumption of multiple origins is problematic for evolutionary biologists who prefer to find that complex structures like fangs … don’t just come and go. If they did, fangs presumably would have popped up in other vertebrates [Science News].

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