Mindlessly copying everything your parents did may seem like a silly thing to do. But from an evolutionary standpoint, not thinking might be the best possible strategy for survival.
This is the counterintuitive idea put forward by researchers at the UK's Universities of Exeter and Bristol. Animals have two choices when it comes to survival - either they can just copy what their parents did, or they can try to adapt new strategies to deal with the information around them. Exeter's Dr. Sasha Dall explains, putting this finding in distinctly human terms:
"From an individual perspective, sometimes sticking to what your parents did may seem a ridiculously stupid thing to do, especially when they can be out of touch with current events. However, it's a different story when you look at it from the perspective of your genes. What we actually found is, in certain circumstances, it can be a more effective method of ensuring long-term survival of your genes than more nuanced strategies. So, surprisingly, this kind of mindless strategy can actually be more effective than the more sophisticated alternative of adjusting to changes you detect in your environment."
It's all because of the interaction between an organism's genes and its environment. Those animals that are in the right environment for their particular genotype will tend to survive and reproduce, passing on their successful genes and, implicitly, a winning strategy for long-term survival. So then, animals can be pretty much assured of continued reproductive success if they just did whatever their parents did, and over multiple generations the unsuccessful organisms will be bred out completely. Eventually, the entire population is made up almost exclusively of animals who are perfectly suited for their environment.
That part isn't all that surprising, as it's one of the basic mechanisms of natural selection. But Bristol's Professor John McNamara takes it a step further by saying the animals who are smart enough to respond to subtle changes in their environment and modify their survival strategies might actually be at a disadvantage:
"The sheer fact you are alive is a big clue, because your parents must have got it right. If you follow their lead, you should get it right too. Using a mathematical model, we've shown this is more successful than the alternative approach of adjusting behaviour to current conditions when the environment changes a bit, but not too much, between generations, and where there is a choice of both good and bad places to be. When you try to adapt to your environment, you can make mistakes which could prove costly or even fatal. Also, this approach may require a lot of time and effort — which again could limit the success it brings on an evolutionary basis."
We can see this phenomenon all the time in nature. Turtles, for instance, swim past lots of perfectly good beaches just so they can reproduce on the particular beach they were born on. This may seem inefficient, even stupid, but it's just a very basic way of hedging their bets and ensuring survival, as Dr. Dall explains:
"This may not seem very smart, but those turtles are actually sticking to the safest bet there could be — the spot where they know their parents successfully gave birth to them. We're not saying that this works for every species or all of the time, but it does shed a bit of light on this interesting area of animal behaviour and evolutionary biology."
Via Ecology Letters.