Poster presentation 12th International Mammalogical Congress

The nuchal ligaments in Carnivora: Speculative relations with sniff trail behavior (#767)

Satoshi Suzuki 1 , Hajime Taru 1 , Daisuke Koyabu 2 , Junpei Kimura 3
  1. Kanagawa Prefectural Museum of Natural History, Odawara, Kanagawa, Japan
  2. The University Museum, The University of Tokyo, Tokyo, Japan
  3. College of veterinary medicine, Seoul National University, Seoul, Korea

It is widely known that the nuchal ligaments are well developed in some species of perissodactyls and artiodactyls. This ligament connects the caudal edge of the skull and thoracic vertebra to support the head weight without interfering the ability to lower the neck during feeding. This ligament is also present in dogs. However, the existence of this ligament has not been well studied in other mammals. Cadavers of several carnivorans including dog, Japanese raccoon dog, red fox, raccoon, Japanese badger, masked palm civet, cat, lion, tiger and Asiatic black bear were dissected to confirm the presence/absence of the nuchal ligament. It was found in all canids dissected (dog, raccoon dog and fox) but not in any other carnivorans. This ligament connects the tip of the first thoracic spinous process and the caudal edge of the spinous process of axis with abundant elasticity.  In contrast to horse and cow, only the funicular part exists and laminar part was not found. The nuchal ligament was not only found in adults but also in fetal stages of felids. Among carnivorans, most canids are engaged in the so-called “sniff-trail behavior” when chasing prey.  We speculate that the nuchal ligament works as an elastic support that continuously supports the head; this is beneficial for sniffing the ground over a long period to follow an invisible prey.