What larger mammals did Britain have and what did they do?

We are currently between Ice Ages, in the Holocene. In Britain, the previous geological time period, the Pleistocene (Ice Age), was interspersed with a series of warm (interglacial) periods in which warm-adapted mammals such as Hippopotamus Hippopotamus amphibius, Barbary Ape Macaca sylvana and Spotted Hyaena Crocuta crocuta migrated north through Europe.