The more I think of it (and I’ve been thinking of it a lot), the more I realise just how amazing that behavior is. Sperm Whales are not prone to forming bonds with other species. This might be relatively common for other whales, but not for Sperm Whales.
Now this particular dolphin might have been picked on and ostracised by other dolphins. Or its malformation simply might have not allowed it to keep up with them. It might have approached the Sperm Whales looking for new ‘travel buddies’, swimming with them, following their path, would have been way easier. So this is clearly convenient for the dolphin.
What’s surprising is that those whales accepted its presence. But there might be an explanation to that as well. There’s calves in that pod (look for the smaller awkward ones). When Sperm Whales swim in big pods they will take turns and while some dive to way deeper waters to hunt, an adult or two will usually stay by the surface with the calves to look after them, until the others come back.
That dolphin might have simply been seen as an extra babysitter, extra protection for their calves in waters full of predators.
So they basically went “Hey you are a little weird, but the kids like you, you can stay and babysit them. There’s Giant Squid leftovers in the fridge, feel free to help yourself”.
on bad days just remember that whales are actually the descendants of ancient horse breeds who thought life on land was shit so they just went back into the ocean and that is always an option you can look into
pre-emptive RIP to billie and daud cuz you know the outsider gonna fuck them up. there ain’t no way they’re gonna successfully waltz into the void and kill the immortal whale god. they’re probs gonna accidentally set delilah free again or some shit. just retire, goddamn.