Even though they aren't genetically diverse as a population, narwhals are doing well, New Scientist reports, adding that this suggests that genetic diversity might not be as important as thought.
Researchers from the Natural History Museum of Denmark assembled the genome of a narwhal from West Greenland and estimated autosomal heterozygosity across its genome. As they report this week in iScience, the researchers found narwhals to have very low genetic diversity when compared to other mammals, even when compared to other Arctic marine mammals like the beluga and bowhead whales and walruses. They further report that narwhals' low genetic diversity does not appear to be due to a recent bottleneck or inbreeding, but has been low for an extended period of time.
Narwhals' gradual decline in a population size might have enabled them to preserve the genetic diversity they needed and avoid the ill effects of a sudden population crash, New Scientist adds.
However, the researchers note that this doesn't mean narwhals won't be affected by climate change. "Our study can't comment on whether narwhals will be able to adapt, or if they have the plasticity to be resilient in these rapid changes," Eline Lorenzen from the Natural History Museum says in a statement.