Do some birds know when other birds of their same species (con-specifics) have died? Do some giraffes mourn their fallen young by performing a ceremony? Do elephants recognize the dead and display some form of “respectful” behavior? These are just some of the questions biologists are trying to answer when it comes to a specific type of animal behavior.
There were several interesting events in Yellowstone National Park this past spring and summer. During a summer enrichment trip to Yellowstone in June 2014, participants spotted a bison carcass in the Lamar Valley. What was taking place around the carcass was fascinating. For about a day, bison gathered around the carcass and formed a barrier. During this bison “funeral”, wolves and coyotes tried to penetrate the barrier to feed without any success. There was a point when the bison must have felt the risks were too high and began to walk away. While this type of behavior may not be rare with bison, it is still not very well understood.
This same scenario played out in Yellowstone earlier in January 2014, but with an interesting twist. Bison seemed to be displaying this “respect for the dead” behavior as they surrounded the carcass of a cow elk. Read about these events here and here.
Even though specific research may be lacking, there are other stories that provide evidence that animals may, in fact, mourn the dead, especially con-specifics. Western scrub jays have been observed summoning others to screech over the body of a dead jay (see here). Teresa Inglesias, one of the lead authors, states that they simply do not know enough to state that this behavior implies that there is an emotional component. However, the researchers cannot rule it out.
Details of an incident with a giraffe were published in the African Journal of Ecology in 2012. Biologists observed a mother giraffe refusing to leave the body of her dead calf. At the time, this was the third recorded incident of this behavior. In 2010, a mother giraffe was observed standing alongside her dead calf over a span of four days. Does this show that animals have a mental model of death?
African elephants have been shown to exhibit a strong preference for ivory and elephant skulls over other objects. This may suggest that elephants would be highly likely to visit the bones of relatives who die within their home range.
Finally, mother chimpanzees have been observed carrying around their dead young for weeks. This rare behavior may show that chimps understand the concept of death and have ways to cope with it.
What is the evolutionary basis for this “mourning” behavior? Are animals aware of the concept of death? Is there an emotional or ritual component to this behavior? If this is strictly a con-specific behavior, how does one explain the bison surrounding the dead elk? Did they “know” each other when the elk was alive?
With each of these questions, researchers must be careful about not attributing human behaviors to these animals. However, these are noteworthy behaviors. Comparative research is needed to show whether any other species show similar responses. Also, more research is needed to try to figure out if these responses have any relationship to specific cognitive or social behaviors.