My favourite animal is the field vole. A tiny, fascinating creature. As a boy I kept a few as pets. You don’t see them often but they are one of our more common mammals. You can see sign of them easily, their tunnels through the grass have neat pile of green droppings and cut grass. The skeletons and skulls are often in owl pellets. Like other rodents their front teeth keep growing, like elephants their distinctive zig zag back teeth do too. They have a lemming like fluctuations in their numbers. They are also pretty cute looking.
Image Fer boei [CC BY-SA 3.0], via Wikimedia Commons