The Curious Case of Dingoes

Abstract

Among all Australian mammals, or for that matter,mammals as a whole, the case for the dingoes has been acurious one. Having arrived in Australia only about4–5,000 years ago, the dingoes are not native to theAustralian fauna, which is dominated by marsupials thathave existed in isolation there for millions of years, and itdid not arrive with the first humans who reached Australiaabout 50,000 years ago (dogs may not have beendomesticated at that time). However, whatever the circum-stances that brought the dingoes to the Australian continent(either with the aid of seafaring Polynesians or by islandhopping), dingoes have become a top predator, and as aplacental mammal, their impact on the native marsupialfaunas is disproportionally large. There are also the unendingcontroversies over the status of the dingo as a pest to becontrolled or as a keystone hypercarnivore that plays a vitalrole in the ecology of the entire continent. Even the name“dingo” could not be traced to any Australian aboriginallanguages, and may be a construct of European colonialsettlers. Thus, aggregated in a single animal is an interestingmixture of unique historic circumstances, placental-marsupialinteractions, as well as the more volatile human prejudicesover its impact on livestock and wildlife.In a continent full of “naive” marsupials, the arrival of alarge placental predator, such as the Australian aboriginesduring the late Pleistocene, can have devastating effects onthe native megafaunas, as shown in recent studies in TightEntrance Cave of southwestern Australia (Prideaux et al.2010). Although few archaeological records exist todocument a similar impact of the dingoes before the arrivalof the Europeans, it is safe to assume that dingoes musthave played important roles in shaping modern marsupialcommunities. Whatever that impact might have been,dingoes are now well integrated in the Australian mammalcommunity and play a major role at the top of the foodchain.Readers of this journal naturally want to know, what isthe dingo? To whom is it related among extant canids? Is ita wolf or a domestic dog? If the former, how do wedistinguish dogs from dingoes? Unfortunately, Purcell’seffort to summarize current research is inaccurate, possiblybiased by the conservation point of view. Data related to thegenealogical relationships of dingoes were largely morpho-logical in traditional studies, but increasingly molecularevidence (mitochondrial and nuclear DNA) is taking over,because of the explosive growth of sequencing technologiesin recent years and because of its far larger dataset withgreater power in resolving phylogenies. This is especiallytrue where extant representatives (the various subspecies ofgray wolves and dog breeds) make up a dense sample of thephylogeny. The latest and most authoritative genome-wide,single nucleotide polymorphisms study (with 48,000 SNPs)suggests that dingoes, along with New Guinea singing dog,represent an ancient breed of dogs that fall in a small cladeincluding the Alaskan malamute, Siberian husky, ChineseShar Pei, Akita, and chow chow (vonHoldt et al. 2010).Curiously, Purcell (p. 30), commenting on vonHoldt et al.(2010), concluded that dingoes are “one of the closestliving relatives of the gray wolf … and most likely the lastform of primitive canid before the domestication of thedog.” Purcell’s statements in this regard are inconsistentwith vonHoldt et al.’s(2010) phylogeny.It is understandable that conservationists may prefer toregard the dingoes as a subspecies of the gray wolf (Canis