Whales and
dolphins have rich 'human-like' cultures and societies
University of
Manchester
Whales and dolphins
(Cetaceans) live in tightly-knit social groups, have complex relationships,
talk to each other and even have regional dialects -- much like human
societies.
A major new study,
published in Nature Ecology & Evolution(Monday 16th
October), has linked the complexity of Cetacean culture and behaviour to the
size of their brains.
The research was a
collaboration between scientists at The University of Manchester, The
University of British Columbia, Canada, The London School of Economics and
Political Science (LSE) and Stanford University, United States.
The study is first of its kind to create a large dataset of cetacean brain size and social behaviours. The team compiled information on 90 different species of dolphins, whales, and porpoises.
It found overwhelming evidence that Cetaceans have sophisticated social and cooperative behaviour traits, similar to many found in human culture.
The study demonstrates that these societal and cultural characteristics are linked with brain size and brain expansion -- also known as encephalisation.
The long list of
behavioural similarities includes many traits shared with humans and other
primates such as:
- complex alliance relationships -- working together for mutual benefit
- social transfer of hunting techniques -- teaching how to hunt and using tools
- cooperative hunting
- complex vocalizations, including regional group dialects -- 'talking' to each other
- vocal mimicry and 'signature whistles' unique to individuals -- using 'name' recognition
- interspecific cooperation with humans and other species -- working with different species
- alloparenting -- looking after youngsters that aren't their own
- social play
Dr Susanne Shultz, an
evolutionary biologist in Manchester's School of Earth and Environmental
Sciences, said: "As humans, our ability to socially interact and cultivate
relationships has allowed us to colonise almost every ecosystem and environment
on the planet. We know whales and dolphins also have exceptionally large and
anatomically sophisticated brains and, therefore, have created a similar marine
based culture.
"That means the
apparent co-evolution of brains, social structure, and behavioural richness of
marine mammals provides a unique and striking parallel to the large brains and
hyper-sociality of humans and other primates on land. Unfortunately, they won't
ever mimic our great metropolises and technologies because they didn't evolve
opposable thumbs."
The team used the
dataset to test the social brain hypothesis (SBH) and cultural brain hypothesis
(CBH). The SBH and CBH are evolutionary theories originally developed to
explain large brains in primates and land mammals.
They argue that large
brains are an evolutionary response to complex and information-rich social
environments. However, this is the first time these hypotheses have been
applied to 'intelligent' marine mammals on such a large scale.
Dr Michael
Muthukrishna, Assistant Professor of Economic Psychology at LSE, added:
"This research isn't just about looking at the intelligence of whales and
dolphins, it also has important anthropological ramifications as well. In order
to move toward a more general theory of human behaviour, we need to understand
what makes humans so different from other animals. And to do this, we need a
control group. Compared to primates, cetaceans are a more "alien"
control group."
Dr Kieran Fox, a
neuroscientist at Stanford University, added: "Cetaceans have many complex
social behaviours that are similar to humans and other primates. They, however,
have different brain structures from us, leading some researchers to argue that
whales and dolphins could not achieve higher cognitive and social skills. I
think our research shows that this is clearly not the case. Instead, a new
question emerges: How can very diverse patterns of brain structure in very
different species nonetheless give rise to highly similar cognitive and social
behaviours?"