Well, I dunno about animal altruism.

When we owned a farmlet near Dunedin (NZ), Demmy, our 16-year-old dog, had a massive stroke that paralysed her. The vet came around that evening and put her to sleep in one of our outbuildings. We put an old rug over her until the morning, when we were going to bury her. In the morning, a friend who was staying with us offered to give me a hand to move her (she was a heavy dog) down to the spot where she was to be buried. He went out to get some gear and came back in looking a bit odd. "Come and have a look at this," he said.

I went out and looked. The rug had been pushed back from Demmy's head, and a vey dead rabbit had been dropped next to her mouth by one Lizzy, one of our cats.

I can only conclude that Lizzy WAS being altruistic when she attempted to "donate" a dead rabbit to her evidently ill friend, the dog.

Can anybody come up with a different but plausible explanation?