ALT Top right: Photograph of two jaw bones with a one cent Euro coin for scale. The bones are a fragment of a mandible of Galanthis baskini from Las Casiones (small, darker specimen, above) and a complete mandible of the extant species Mustela nivalis (lesser weasel; lighter coloured specimen below). Image: Alberto Valenciano. Top left: blue rectangle is a cover image from the journal Palaeontology. Bottom: Illustration of body mass along the branches of the tip-dated Bayesian MCC tree, showing the ancestral body mass for each clade; illustrated specimens (not to scale): Lutra lutra, MNCN-3666; Vormela peregusna, IVPP-OV519; Zdanskyictis minimus, PMU-21788; Mustela putorius, MNCN-3846; Mustela nivalis, MNCN-14416; Mustela erminea, MNCN-14372; Neogale vison, MNCN-14417; Galanthis baskini, KS-9a; Martes americana, FMNH-51372.