Is the extant southern short‐tailed opossum a pigmy sabretooth predator?

Abstract

AbstractHypertrophied canines evolved several times among mammalian carnivores. Several palaeobiological hypotheses related to sabretooth evolution and killing behaviours have been suggested based on biomechanical and functional considerations. However, the lack of well‐studied extant analogues makes it difficult to test these hypotheses. Here we propose the South American short‐tailed opossum Monodelphis dimidiata as a living analogue of extinct sabretooth predators. Our morphological analysis shows that M. dimidiata not only has relatively the largest canines among extant marsupial carnivores, but they are also within the range of those of sabretooth predators. It also has cranial adaptations for a wide gape typical of sabretooth carnivores. The small body size of this species allows further biological studies that can provide useful information to understand the evolution, behaviour and physiology of extinct sabretooth carnivores.