Came across this post by Marc Beckoff, PhD where he discusses a video of an adult dog ritually burying a dead puppy. He doesn’t apply any motivation to the action… we don’t know whether the dog even knew the puppy. The interesting thing is the action itself.
Read here: “A Dog Funeral: Adult Dog Ritually Buries a Dead Puppy”.
Goes to show that there is still so much to be learned about animals and the “why’s” of things.