“…Such adaptations have been described in a comparative framework since the early 20th century ( Shimer, 1903 ). Osteological and muscular characters linked with fossoriality in extant mammals have been the focus of many morphoanatomical studies in the last few decades, for example, on monotremes ( Gambaryan et al, 2015 ), marsupials ( Warburton et al, 2013 ), xenarthrans ( Vizcaíno, Fariña & Mazzetta, 1999 ; Vizcaíno & Milne, 2002 ; Olson et al, 2016 ), rodents ( Gasc et al, 1985 ; Thorington, Darrow & Betts, 1997 ; Elissamburu & Vizcaíno, 2004 ; Lagaria & Youlatos, 2006 ; Samuels & Van Valkenburgh, 2008 ; Elissamburu & De Santis, 2011 ), true moles ( Rose et al, 2013 ), golden moles ( Gasc et al, 1986 ), and mustelids ( Ercoli et al, 2013 , 2015 ; Moore et al, 2013 ; Rose et al, 2014 ). Many of these studies have focused on the forelimb of scratch-diggers, that is, animals that dig by alternately flexing and extending their limbs to cut and loosen the soil with their claws ( Hildebrand, 1974 ), and have identified several anatomical markers linked with fossoriality in the limb bones of scratch-digging mammals (e.g., enlarged medial epicondyle in the humerus, elongated olecranon process in the ulna), which have been used to define quantitative measurements to assess degrees of fossoriality among these groups (see reviews in Hildebrand, 1985 ; Reichman & Smith, 1990 ).…”