Last week I gave you a couple of skulls from the collections in the Dead Zoo to have a go at identifying:
It’s pretty obvious that they are rodents, based on those paired incisors. But there are a lot of rodent species out there…
These are small and, based on the size, we can immediately rule out all anything bigger than a Brown Rat. The anterior portion of zygomatic process, where it meets the maxilla (the front parts of the cheek bones) are broad and triangular, narrowing to very fine arches where it meets the temporal porocess (the rear part of the arch of the cheek bone). This is something I associate with voles.
The teeth are also distinctively ‘voley’ with their zig-zagging cusps.
There are still a lot of vole species out there, but if you’re familiar with identifying specimens from owl pellets in the UK you’ll probably recognise that the specimen on the left has a very distinctive second molar, with a small fifth cusp. This is a tell-tale indicator of the Short-tailed Field Vole Microtus agrestis (Linnaeus, 1761), while the more rounded cusps of the specimen on the right are more in keeping with a Bank Vole Myodes glareolus (Schreber, 1780).
So congratulations to Chris Jarvis in the comments, and to the Scarborough Museum and Galleries Collections Team on Twitter, who managed to leave sufficiently clear but cryptic clues to the identity of these skulls:
I hope you enjoyed these smol skulls and the pointers provided to separate them.