New World porcupines originated in South America and dispersed into North America between 4 and 3 million years ago. Prehensile-tailed porcupines today live in tropical forests of Central and South America. In contrast, North American porcupines (Erethizon dorsatum) are thought to be adapted to higher-latitude temperate forests, with a larger body, shorter tail, and diet that includes bark. In a paper published this week in the journal Current Biology, paleontologists described functionally important features of the skeleton of the extinct porcupine Erethizon poyeri, the oldest nearly complete porcupine skeleton documented from North America, found in the Early Pleistocene of Florida.
Porcupines are a type of rodent, and their ancestors likely originated in Africa more than 30 million years ago.
Their descendants have since wandered into Asia and parts of Europe by land, but their journey to South America is a particularly defining event in the history of mammals.
They crossed the Atlantic Ocean — likely by rafting — when Africa and South America were much closer together than they are today.
They were the first rodents to ever set foot on the continent, where they evolved into well-known groups like guinea pigs, chinchillas, capybaras and porcupines.
Some took on giant proportions. There were lumbering, rat-like animals up to five feet long, equipped with a tiny brain that weighed less than a plum. Extinct relatives of the capybara grew to the size of cows.
Porcupines remained relatively small and evolved adaptations for life in the treetops of South America’s lush rainforests.
Today, they travel through the canopy with the aid of long fingers capped with blunt, sickle-shaped claws perfectly angled for gripping branches.
Many also have long, prehensile tails capable of bearing their weight, which they use while climbing and reaching for fruit.
Despite their excellent track record of getting around, South America was a dead end for many millions of…
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