False killer whales, interacting with bottlenose dolphins off the New Zealand coast

A few years ago, I wrote an essay against the idea that nature was always nasty (see: “Nature, Not Always “Red in Tooth and Claw”). I think the whole essay pivoted on one important quote from the primatologist Frans deWaal, who explained why it is misguided to focus solely on the colder, cruel side of evolution. He wrote:

“The error is to think that, since natural selection is a cruel, pitiless process of elimination, it can only have produced cruel and pitiless creatures. But nature’s pressure cooker does not work that way. It favors organisms that survive and reproduce, pure and simple. How they accomplish this is left open” (2009: 58).

From there I pointed out several of examples of cooperation and altruism in nature, mostly among primates, but also in other mammal species. I would like to add another one that I learned from the BBC’s Blue Planet II: the relationship between false killer whales  (Pseudorca crassidens) and bottlenose dolphins (genus Tursiops). As the inimitable David Attenborough narrates in the clip below, pods from the two species were seen meeting near the New Zealand coast, and the audience is led to expect hostilities or predation… “But then, something truly extraordinary happens.”

From the video clip and the website, we learn that the two species often travel together in groups of up to a thousand animals. They socialize, change their vocalizations when around each other, rest together, and even hunt together, sometimes for years and over long distances.

I learned about this example months ago, but I have an ulterior motive for bringing it up now. I’ve seen people write online about how conflicts between groups of humans (cultures, populations, races, religions) are inevitable, and that this is due to the laws of nature and competition.

This strikes me as such an oversimplification of nature and animal behavior. Yes, conflicts exist in humans and in other species, even in cetaceans. But here we have an example of long-term cooperation between not just different populations or species. Rather, taxonomically speaking, false killer whales and bottlenose dolphins aren’t even in the same subfamily of cetaceans, and their two lineages may have diverged as far back as 8 million years ago (Vilstrup et al 2011).

The point isn’t that we are just like cetaceans, or that we should model our behavior after them. The point is that we shouldn’t accept at face value that all interactions between groups, populations, species, etc. are inevitably hostile. Examples from nature suggest that things are more complicated than that, and that genetic proximity may not be as important as are shared common interests.

References

de Waal F. 2009. Primates and Philosophers: How Morality Evolved. Princeton Books. Link

Vilstrup JT, Ho SY, Foote AD, Morin PA, Kreb D, Krützen M, Parra GJ, Robertson KM, de Stephanis R, Verborgh P, Willerslev E. Mitogenomic phylogenetic analyses of the Delphinidae with an emphasis on the Globicephalinae. BMC evolutionary biology. 2011 Dec;11(1):65. Link