Scientists who sequenced the Indian wolf’s genome for the first time have said that the land mammals could be far more endangered than previously recognised.
The findings, published in the journal Molecular Ecology, reveal the Indian wolf to be one of the world’s most endangered and evolutionarily distinct gray wolf populations. The study indicates that Indian wolves could represent the most ancient surviving lineage of wolves.
Till now, the Indian and western Asian wolf populations have been considered as one population, however, the study’s finding that Indian wolves are distinct from western Asian wolves indicates their distribution is much smaller than previously thought.
The Indian wolf is restricted to lowland India and Pakistan, where its grassland habitat is threatened primarily by human encroachment and land conversion.
“Wolves are one of the last remaining large carnivores in Pakistan, and many of India’s large carnivores are endangered,” said lead author Lauren Hennelly, a doctoral student with the UC Davis School of Veterinary Medicine’s Mammalian Ecology Conservation Unit. “I hope that knowing they are so unique and found only there will inspire local people and scientists to learn more about conserving these wolves and grassland habitats.”
The authors sequenced genomes of four Indian and two Tibetan wolves and included 31 additional canid genomes to resolve their evolutionary and phylogenomic history. They found that Tibetan and Indian wolves are distinct from each other and from other wolf populations.
The study recommends that Indian and Tibetan wolf populations be recognized as evolutionarily significant units, an interim designation that would help prioritize their conservation while their taxonomic classification is reevaluated.
“This paper may be a game-changer for the species to persist in these landscapes,” said co-author Bilal Habib, a conservation biologist with the Wildlife Institute of India. “People may realize that the species with whom we have been sharing the landscape is the most distantly divergent wolf alive today.”
Gray wolves are one of the most widely distributed land mammals in the world, found in snow, forests, deserts and grasslands of the Northern Hemisphere.
Wolves may have survived the ice ages in isolated regions called refugia, potentially diverging into distinct evolutionary lineages.
Recent genomic studies confirmed that the Tibetan wolf is an ancient and distinct evolutionary lineage. However, until this study, what was known about the evolutionary history of Indian wolves was based on mitochondrial DNA evidence, which is inherited only from the mother. That evidence suggested that the Indian wolf diverged more recently than the Tibetan wolf.
In contrast, this study used the entire genome — the nuclear DNA containing nearly all of the genes reflecting the wolf’s evolutionary history. It showed that the Indian wolf was likely even more divergent than the Tibetan wolf.
Both Tibetan and Indian wolves stem from an ancient lineage that predates the rise of Holarctic wolves, found in North America and Eurasia. Sacks said this study indicates Indian wolves could represent the most ancient surviving lineage.
“I knew that if we sequenced the wolves and the results indicated a divergent lineage, answering that question could really help their conservation at a policy scale that could trickle down and bolster local efforts to help protect these wolves,” Hennelly said.