Burying beetles (genus Nicrophorus), known for their biparental care, have been the focus of behavioural ecological studies for many years. N. vespilloides is distributed across most of the northern hemisphere, but recent genetic evidence from North America clusters Alaskan specimens outside the rest of the continent.
Using additional genetic data, researchers demonstrated two distinct groups, corresponding to those from Canada versus those from Alaska. In fact, the Alaskan samples clustered with Palearctic samples. Trapping individuals from both regions and setting up breeding trials, the researchers found a mating barrier preventing off-spring from reaching maturity, confirmed the genetic evidence.
The study concludes that N. vespilloides is in fact two species, and suggest readapting a previously used name, N. hebes, for the Nearctic (minus Alaska) group.