Seen over at Mike the Mad Biologist. This 15 second video depicts an altruistic tortoise:
Hope this video plays OK, since I have absolutely no knowledge of Twitter, the source. But I know you'll enjoy it if you watch.
The connection to Ultrarunning? In various races I have personally participated in helping a runner in distress, and myself have been the recipient of such help. I suspect that this experience is actually the norm for Ultrarunners--we'll always stop and help somebody who needs it, even if it throws us off our planned race.
It's just what you do.