Dolphins indulge in elite societies and cliques just like humans do, scientists find

Saturday, August 04, 2012 by: Jonathan Benson, staff writer
Tags: dolphins, elite societies, intelligence

(NaturalNews) One of the smartest mammals on the planet apart from human beings, dolphins have long fascinated scientists because of their incredible intellectual abilities, which include things like their amazing aptness at solving problems, planning ahead, and even experiencing emotions. And a new study published in the journal Nature Communications adds further insight into the complexity of dolphins, having found that, just like humans, dolphins tend to form elite social groups, and prefer the company of other dolphins who share the same skills as them.

For 22 years, Janet Mann and her colleagues from Georgetown University studied the behavioral habits of bottlenose dolphins living in Australia's Shark Bay to learn more about how they interact socially. The team observed in particular 36 dolphins that had learned how to use sea sponges on their noses to protect them from injury while foraging, as well as 69 other dolphins living in the same area that had not learned the technique.

At the onset of the study, the research team observed that the unique sponging technique had originally been discovered by a single dolphin, later named "Sponging Eve," who researchers observed to have scraped her nose on some rough sand while searching for food. Sponging Eve figured out a way to break off part of a sea sponge, they discovered, which she then attached to her nose to protect it.

Based on previous knowledge and study of animal behavior, the team assumed that this valuable hunting tool would eventually spread throughout the entire dolphin community living in Shark Bay, and even beyond. Most animals, after all, tend not to belong to any specific culture or subculture among their own species, per se, which means their skills and survival techniques are indiscriminately passed down to others living in the same area.

Dolphins appear to be just as cliquish as humans

But as the years passed on in the study, only a few of the dolphins picked up the sponging skill, while the rest appeared to have been excluded from this useful knowledge. And upon investigation, the researchers noted that Sponging Eve had essentially reserved her knowledge of the technique for her close friends and offspring, while the rest of the dolphins outside her social group remained unaware of it.

"Spongers were more cliquish, had more sponger associates and stronger bonds with each other than with non-spongers," said the authors about the dolphins who learned the sponging technique compared to the others. "Like humans who preferentially associate with others who share their subculture, tool-using dolphins prefer others like themselves, strongly suggesting that sponge tool-use is a cultural behavior."

Prior to uncovering this fascinating subculture among dolphins, most animal researchers assumed that all animals, including dolphins, passed on traits for practical reasons, without any regard for social situations outside, perhaps, their own family unit. But it appears as though dolphins are once again a cut above most other animals in terms of mental proficiency, as the traits of "inclusive inheritability" and culture can no longer be attributed exclusively to humans.

"Homophily (the tendency to associate with others who are similar to one's self) based on tool-using status was evident in every analysis," added the researchers about the dolphins. "[A]lthough kinship, sex and location also contributed to social preference."

Sources for this article include:

http://www.telegraph.co.uk

http://news.yahoo.com

http://news.sciencemag.org