November 28, 2013
Brazilian Tigrina Is Not One, But Two Separate Wild Cat Species
redOrbit Staff & Wire Reports - Your Universe Online
Researchers studying the evolutionary history of wild cats have made a shocking discovery – while scientists had long assumed there was a single species of the Brazilian tigrina, they have now confirmed there are actually two of them.
The remarkable study, which is published in Wednesday’s edition of the journal Current Biology, reports there are two separate populations of the housecat-sized Brazilian wild cats – one living in the northeastern part of the country, and one living in the south. Since there is no evidence of interbreeding between the two groups, the investigators declare they are two distinct species.
“We used several different types of molecular markers to investigate the evolutionary history of these species,” lead researcher Dr. Eduardo Eizirik, from the Pontifical Catholic University of Rio Grande do Sul in Porto Alegre, Brazil, told Jeremy Coles of BBC Nature. “These [molecular markers] evolve at different rates, which helps in the sense that they provide information on different time frames.”
According to National Geographic reporter Carrie Arnold, Dr. Eizirik and his colleagues were attempting to understand the evolutionary history of what they believed to be three species (the tigrina, the Pampas cat and Geoffroy’s cat) belonging to the genus Leopardus.
They collected and analyzed DNA samples from over 200 different cats, discovering evidence of interbreeding between the Pampas cat and the northeastern tigrina, and the Geoffroy’s cat and the southern tigrina, but not the two different tigrina populations, Arnold explained. The investigators have recommended allowing the northeastern tigrina to keep its current name of L. tigrinus, and referring to the southern species as L. guttulus.
“Our study highlights the need for urgent attention focused on the Brazilian northeastern tigrinas, which are virtually unknown with respect to most aspects of their biology,” Dr. Eizirik noted in a statement. Likewise, he told National Geographic “very little was – and still is – known about this species. There have been some initial studies on its diet, but still most of its basic biology remains poorly known, including density, habitat use, and population trends.”
The researchers assert the two different species are better suited to different environments, with the northeastern cats making their homes primarily in savannahs, dry shrub lands and forests; and the southern species living in denser and wetter Atlantic forests. Furthermore, the discovery that the tigrina is actually two different types of cats could have important implications when it comes to conservation efforts.
“Recognizing a distinct tigrina species in Brazil highlights the need for urgent assessment of its conservation status… and it may be found to be threatened,” Dr. Eizirik told Coles. “[These results] illustrate how much is still unknown about the natural world, even in groups that are supposed to be well-characterized, such as cats. In fact there are many basic aspects that we still don't know about wild cats, from their precise geographic distribution and their diets to even species-level delimitation, as in this case.”