Morphometric analysis of jaguar (panthera onca) and tiger (panthera tigris) skulls - species on the "red list" of the international union for conservation of nature (IUCN)

Abstract

In Romania, the two species covered by this study - the jaguar (Pantheraonca) and the tiger (Pantheratigris) are species found only in zoos or circuses. Romania, as an European Union border state, may be transited or used by collectors or by smugglers of exotic species, especially since the two species are subject to an extremely strict control. The tiger (Pantheratigris) according to the IUCN Red List is an endangered species and the jaguar (Pantheraonca) is nearly endangered. These species have a common ancestor - Proailuruslemanensis - but have evolved in different environments, Indian jungles and the Siberian taiga (the tiger), all North and South American habitats (the jaguar). In order to perform the morphometric analysis there were used skulls of three adults tigers (Pantheratigris) and from a jaguar male (Pantheraonca), skulls found under administration of the discipline’s museum. Description, identification and homologation were made according to N.A.V .2005. Following the studies and measurements carried out, it appears that there is a little difference in size of the skulls of the two species, especially as the jaguar, unlike the tiger, is climbing, and the whole body must be lighter and smaller. The described and used graphics and reference points allow performing complex measurements, both on anatomically prepared skulls and on radiological images. It is observed that the jaguar’s skull is slightly smaller than the tiger’s one. The measurements that make the differences between the two skulls are those of the jaw. There are also differences on the dorsal and ventral facets of the skull as on the lateral side. There were identified eight reference points on which it can be determined to which species the skull being analyzed belongs.