The fast-breeding rat could one day evolve to be the size of a cow, according to scientists, who suggest extinctions higher up the animal size chain could leave empty evolutionary slots for the rat to bulk up and fit itself into.
The giganto-rat claim comes from quotes given by University of Leicester geologist Dr Jan Zalasiewicz, who says the expansion of the rat is simply a matter of time and space. "Given enough time, rats could probably grow to be at least as large as the capybara, the world’s largest rodent, that lives today, that can reach 80 kilos," imagines the doctor, adding: "If the ecospace was sufficiently empty, then they could get larger still."
Which sounds like a good reason to do all we can to stop elephants going extinct. And there is form for cow-rats on Earth, as three million years ago the Josephoartegasia monesi existed, which was a rodent the size of a large bull that weighed around a tonne. You wouldn't want that living in your walls. [Daily Mail]
Image credit: Rats from Shutterstock