Felids fighting for survival

Long before humans left Africa to conquer the rest of the world, the first felids started their bid for world domination from their native Asia. Genome research has shown that the last common ancestor of today's cat-like species lived in Asia some 10.8 million years ago, and that its descendants started to migrate to Africa and the Americas 9 million years ago (Annu. Rev. Genomics Hum. Genet. (2005) 6, 407–429). Subsequent expansions were complex and sometimes even involved the return of new species to the lands of their predecessors. For instance, the common ancestors of puma and cheetah migrated to North America in one of the earliest waves. Much later the puma moved to South America and then back to North America, while the cheetah returned to Asia, and moved from there into Africa where it is found today. Their relatively rapid movements look less surprising when one considers their lifestyle, which is based on large territories. Young animals are known to migrate long distances in search of a new territory. Thus, by the time humans started to expand out of Africa, cats had become dominating predators on five continents, winning the battle against the marsupial carnivores in South America. Those two-legged omnivores that started to spread out around the globe may have looked harmless to their contemporary felids, but, as hunters with ever-improving armoury, they became at first a competitor and in recent centuries a direct threat to the hitherto invincible big cats. For many decades, until the 1970s, some species, such as tigers in China, were considered as pests and hunted down systematically. Today, hunting is tightly controlled, but the disappearance of habitats and prey stocks poses severe problems to many of the surviving species of felidae, as a brief tour will show. Tigers without borders In 2010, the WWF used the traditional Chinese calendar's year of the tiger to attract additional attention to the plight of this iconic carnivore (Curr. Biol. (2010) 20, R495), of which less than 3,200 individuals are believed to survive in the wild (compared to some 100,000 a century ago). Until recently, China hosted four separate subspecies, but, for the South China tiger (Amoy tiger, Panthera tigris amoyensis), protection status granted in the late 1970s after extensive hunting appears to have arrived too late. In 2007, the authorities concluded that there is no evidence for the sustainable survival of this subspecies in the …