The humble rodent “thumb” may not seem like an obvious window into evolution, but its keratinized tip – the unguis (hoof, claw, or nail) – turns out to reveal striking insights into rodent history and ...

Researchers (left to right) Gordon Shepherd, Anderson Feijó, Lauren Johnson, and Rafaela Missagia, working in the Field Museum’s mammal collections. Picture a squirrel eating an acorn. It’s holding ...

Humans and many rodents share one feature in common that may come as a shock: thumbnails. Most people would think that rodents only have sharp claws, but the majority of these mammals actually have ...