Most rodents can't resist the lure of fried coconut slivers slathered in peanut butter.But, as a group of mammalogists learned through trial and error, that bait will not tempt the shrew-rats of Luzon Island.
'We weren't catching any of them,' says Eric Rickart, vertebrate zoology curator at the Natural History Museum of Utah, of an expedition to Luzon, in the Philippines, to find shrew-rats in 1988. “We knew they were there, but we didn’t know how to trap them.'
That is, until, days before the expedition’s end, when Rickart and his colleagues accidentally trapped two Rhynchomys, also known as shrew- or tweezer-beaked hopping rats. The picky eaters turned up their long, thin rodent noses at the soft fruits, nuts, mushrooms, and insects that mammalogists offered them. But when a researcher gave an earthworm to a shrew-rat they’d accidentally captured, Rickart says, 'it just slurped it down, like a noodle.'
That gastronomical breakthrough “has been responsible for the discovery of a lot of new species,” on later expeditions to the Philippines, says Larry Heaney, a curator of mammals at the Field Museum in Chicago. Among them is the discovery of two new species of tweezer-beaked hopping rats, Rhynchomys labo and Rhynchomys mingan, which Rickart and Heaney described for the first time Thursday in the Journal of Mammalogy and named for the mountains they were found on, Mount Labo and Mount Mingan.