Discovery of how animals, similar to humans, have the desire to experience some kind of death ritual to help with the processing of the dead and the need to pay respects to the dead.
A lot of species have a "generalized response" to a death and it has been observed that creatures too, feel emotions such as sadness and grief.
Elephants, dolphins, chimpanzees, baboons, gorillas etc all gather information about the unresponsiveness of individuals around them, and then they tend to participate in some kind of death ritual.
Since it is still rare for humans to observe a natural death in the wild, we get to understand that this information that is being gathered, will continue to be added onto as time goes on.
However, it's an important reminder that not only it is rare for us humans to see a natural death (most deaths are from diseases or accidents) that we take the available evidence thats provided now, which suggest mourning does occur in the wild, and that we are not so unique in this sense.
Animals are mysterious and majestic, yet, if we allow ourselves to commune and observe them, then we can learn much more about life death, death rituals and grief.