Environment 1 April 2021 By
Culture was once thought to be restricted to humans. But we are discovering more and more examples in animals. In a paper reviewing evidence from several earlier studies that is published in Science this week, zoologist Andrew Whiten at the University of St Andrews, UK, writes that there has been “an explosion of discoveries” showing that animal culture is far more widespread and diverse than we imagined. New Scientist quizzed him about the work.
Michael Le Page: Many readers will know that apes and whales have culture, such as tool use in chimpanzees, but you say that even insects have it.
Andrew Whiten: That is the big surprise. The evidence was really just published in the last few years. So some of us are still reeling from that and thinking, “Well, wow, culture is everywhere.” It’s the reach of animal culture across an increasing range of species that’s one of the main points of my paper.
Can you give an example of insect culture?
There’s good evidence for what’s called mate choice copying in fruit flies. So if female fruit flies watch a male who’s been dusted green by experimenters mate with a female, later on, if given a choice, those females will prefer green-dusted males. The virgin females are learning, “If all the girls like this kind of chap, he must be a good one to go for.” The reason that you can talk about cultural transmission is that if other females watch those females mating, they inherit that same bias, and so on. It is like an incipient tradition.
In bumblebees there are examples of particular foraging techniques that again pass from bumblebee to bumblebee to bumblebee.
What exactly do researchers mean by animal culture?
It is basically behaviour that is passed from one individual to another, spreads across a group and becomes a group characteristic. It may be passed down many generations.
And fish can have culture, too?
Yes, fish have been shown both in the wild on coral reefs and in the lab to learn things like foraging routes socially. A fish will swim with a shoal a particular route, it will learn that route and then if it’s tested by itself, that’s the route it will follow.
Your paper says culture might also be much more extensive in great apes than we thought.
Yes, that’s still controversial. Great apes do this behaviour Caroline Schuppli [an evolutionary biologist at the University of Zurich in Switzerland] has dubbed “peering”, where a juvenile is staring at someone using a tool in a particular way, or whatever. In the next hour or so, it will start trying to do the thing that it had been watching. Schuppli has enumerated something close to 200 contexts in which peering occurs in orangutans. Using this measure of peering suggests that culture is even more all-pervading than we expected. Much of what apes learn in their first few years they may learn from others. We might, indeed, be so far missing much of culture.
Alongside the loss of biodiversity, are we losing a lot of animal culture before we even know that it exists?
Yes. A chimpanzee research group has shown that habitat degradation leads to degradation in the behaviour repertoires of chimpanzees, which we now think of as largely culturally determined. One has to imagine, given the state of the world, that this kind of effect may become more and more common. However, as we increase our understanding, we may be in a position to reintroduce cultures that have been lost.
How do we reintroduce animal cultures?
Some birds reared in captivity have lost the migratory pathway. To get them migrating again, they can be imprinted on microlight aircraft. It’s been done with cranes, geese and swans. Another situation is where animals are being reintroduced into the wild. When golden lion tamarins were first released, they had enormous mortality. They did not know what predators to avoid, and so on. So now conservationists are trying to give animals back some culture before they’re released into the wild.
The United Nations Environment Programme has sponsored workshops recently, developing a number of principles for how what we’ve learned about animal culture can be built into conservation politics, policies and conservation practices.
Not all human culture is good. Can animal cultures also be bad?
In principle, yes. If a culture gets too strong and the environment changes, it is no longer adaptive. The Achilles’ heel of culture, which we see in the human case, can be that individuals end up blindly following the cultural norm when it’s no longer relevant. But compared with genetically based evolution, cultural evolution can be very nimble and fast, as long as some individuals do innovate.
What do you say to people who aren’t convinced animals have culture?
Of course, culture in non-human animals shows vast differences from human culture. That’s obviously true. But what is shared is social learning and the way this can lead on to traditions. That does seem to be widespread. And it has implications for evolutionary biology, which really has to accommodate this second form of inheritance, which can in turn lead to a second form of evolution – cultural evolution.
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