Genome-wide Evidence Reveals that African and Eurasian Golden Jackals Are Distinct Species

Abstract

The golden jackal of Africa (Canis aureus) has long been considered a conspecific of jackals distributed throughout Eurasia, with the nearest source populations in the Middle East. However, two recent reports found that mitochondrial haplotypes of some African golden jackals aligned more closely to gray wolves (Canis lupus), which is surprising given the absence of gray wolves in Africa and the phenotypic divergence between the two species. Moreover, these results imply the existence of a previously unrecognized phylogenetically distinct species despite a long history of taxonomic work on African canids. To test the distinct-species hypothesis and understand the evolutionary history that would account for this puzzling result, we analyzed extensive genomic data including mitochondrial genome sequences, sequences from 20 autosomal loci (17 introns and 3 exon segments), microsatellite loci, X- and Y-linked zinc-finger protein gene (ZFX and ZFY) sequences, and whole-genome nuclear sequences in African and Eurasian golden jackals and gray wolves. Our results provide consistent and robust evidence that populations of golden jackals from Africa and Eurasia represent distinct monophyletic lineages separated for more than one million years, sufficient to merit formal recognition as different species: C. anthus (African golden wolf) and C. aureus (Eurasian golden jackal). Using morphologic data, we demonstrate a striking morphologic similarity between East African and Eurasian golden jackals, suggesting parallelism, which may have misled taxonomists and likely reflects uniquely intense interspecific competition in the East African carnivore guild. Our study shows how ecology can confound taxonomy if interspecific competition constrains size diversification.

Rediscovering a forgotten canid species

“…A single Canis aureus haplotype has been reported from Egypt (Fig. 4) [15]. This specimen is from the Sinai Peninsula, close to the border between Egypt and Israel.…”

“…Recent publications [13][14][15] have identified this animal as a separate species, more closely related to the Holarctic grey wolf than to the golden jackal. Gaubert et al [13] suggested the existence of both the golden jackal and African wolf in North and West Africa.…”

“…The presence of a wolf relative in North and West Africa was indicated in the early literature [9][10][11][12], but until recently [13][14][15] largely ignored in the modern literature. Here we demonstrate the presence of a species closely related to the Holarctic wolf in Africa and discuss its taxonomic status and morphology.…”

“…Morphological features characteristic of the African wolf are heavy build and wider head, as well as some traits of the pelage. Koepfli et al [15], using both mtDNA and autosomal loci, found evidence for African and Eurasian golden jackals as distinct species and found no evidence for the existence of both the golden jackal and the African wolf in Africa. They also estimated the divergence times and found an estimate of 1.9 Ma for the golden jackal and the African wolf and 1.3.…”

Genome of the Tasmanian tiger provides insights into the evolution and demography of an extinct marsupial carnivore

“…In total, 11,254 groups of orthologous genes were retained for comparative genomic analyses (Supplementary Table 9). We used published phylogenies of all included species to construct a fixed tree topology 104,105 used in all comparative genomic analyses ( Supplementary Fig. 8).…”