Golden jackals of Africa and
Eurasia are actually two distantly related species—and one is a new
species of wolf, a new study shows.
Africa's golden jackal (pictured, an animal in Tanzania's Ngorongoro Conservation Area) is actually a type of wolf.
by Carrie Arnold
Jackals, the tricksters of traditional folklore, have fooled us yet again.
The golden jackal, which lives in East Africa and Eurasia, is
actually two distantly related species—and one of them is a new species
of wolf, a new study says.
Dubbed the African golden wolf, it's the first new species of canid—a group that includes wolves, coyotes, and jackals—discovered in 150 years. Africa is also home to two other wolf species, the gray wolf and Ethiopian wolf.
Though golden jackals look mostly the same—the Eurasian animals are
slightly smaller than the African ones, with a narrower skull and
slightly weaker teeth—in-depth analysis of their DNA revealed two
species that have evolved separately for millennia.
"I was very surprised," said study leader Klaus-Peter Koepfli, a biologist with the Smithsonian Conservation Biology Institute in Front Royal, Virginia.
Koepfli proposes renaming the African golden jackal the African golden wolf (Canis anthus), while retaining the original species name for the Eurasian golden jackal (C. aureus).
Sniffing Out Species
Scientists have wondered if golden jackals were more than one species for years.
In 2012, biologist Philippe Gaubert, of the University of Montpellier in France, published
a paper showing that African golden jackals appeared to be a subspecies
of gray wolf that's separate from the Eurasian jackal.
Gaubert used snippets of jackal mitochondrial DNA, which is passed on by mothers, for his analysis.
Koepfli found these results interesting, and wanted to verify them
using more samples from a broader geographic area and more data from
across both the jackal and gray wolf genomes.
In doing so, he expected to replicate Gaubert's earlier work—but that's not what happened.
By examining 38 different genetic markers of 128 canid
specimens—including golden jackals from Kenya, North Africa, and
Eurasia; African gray wolves; and domestic dogs—Koepfli confirmed that
African and Eurasian golden jackals are two separate species. Yet he
also discovered that the African golden jackal is not a gray wolf
subspecies.
Instead, he discovered the African golden jackal is a new wolf
species of its own, and that this species and the Eurasian golden jackal
are distant cousins, having last shared an ancestor about a million
years ago. The research appeared July 30 in the journal Current Biology.
"Airtight Case"
Gaubert stands by his original work, saying that although he finds
the new study to be high-quality work, he isn't yet convinced that the
African golden wolf is a new species. For instance, he says scientists
have yet to tease apart some conflicting results in the DNA analyses.
"There's still a lot of work to be done," he said.
Greger Larson, a bioarchaeologist at the University of Oxford in the U.K., is convinced by the new research.
"They have phenomenal data and they do a nice series of analyses. It's a super airtight case," Larson said.
So why do the African golden wolf and the Eurasian jackal look the same if they're distantly related?
Study leader Koepfli says that the same evolutionary pressures likely
influenced the animals' evolution. For instance, the canids' harsh desert habitats could have led to their small, lean bodies and light coats, which don't absorb as much sunlight.
"We're finding that the genetic information can tell us a very different story about animals," Koepfli said.
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