Co-author Andrew King of Swansea University added that the sneezes act as a type of quorum, where the sneezes have to reach a certain threshold before the pack changes its activity.
“Quorum-like responses occur in lots of different species,” King said. “For example, ants or bees use quorums when moving to new nest sites. In the case of bees, which dance to direct one another to new sites, once the number of bees at a site reaches a quorum, the bees begin an additional recruitment strategy to dancing, known as piping.”
Meerkats also use quorums to “vote” by emitting moving calls before heading off to a new foraging patch. Prior research has also determined that white-faced capuchin monkeys emit trills and, if the vocalizations reach a certain threshold, the monkeys will collectively depart.
Even bacteria, King said, “use quorums to coordinate gene expression according to the density of their local population,” so the process does not necessarily require substantial, if any, brain power.
For African wild dogs, the sneezing acts like democratic voting, such that each individual in a pack may participate and have a vote count. As for human voting, however, the system does not always seem fair.
The researchers noticed if the dominant male and female within each African wild dog pack sneezed, fewer additional sneezes were needed before the group left the resting site.
“However,” Walker said, “if the dominant pair were not engaged, more sneezes were needed — approximately 10 — before the pack would move off.”
The researchers are not yet certain if the sneezes of dominant and subdominant dogs are acoustically different. How dominance is established in a pack also remains unclear, but age appears to be a factor, with younger dogs tending to be more dominant, Jordan said.