Image Credit: Thomas Haaland, CC BY-SA 2.0
Previously on this site I’ve summarised an article I wrote linking some concepts from behavioral ecology with evolutionary biology. Now I’m back to say a bit more about what behavioral ecology actually is. Being introduced to the field of behavioral ecology was what sparked me to actually consider a career in science. It’s a fascinating and beautiful field, and I hope I can show you why!
(Inspired by “An introduction to behavioural ecology” – Davies et al. 2012.)
Watching and wondering
It’s a sunny spring day. Imagine you’re watching a bird out in the grass. You’re in a park, or just looking out your kitchen window. At first you might just be glad to see that you know what species it is – say a starling. But you start watching more closely. You realize it’s looking for food. Maybe it finds a larva, and holds it in its beak, continues looking. After a minute, or two, or ten, you’ve amassed a whole host of questions. Is it taking every bug it finds, or only choosing those of a particular type or size? Why is it foraging exactly here? Why is it alone and not in a flock? (If you were watching sparrows it would have been vice versa.) You saw the starling find several prey items. It disappeared for a while, and returned with an empty beak. It probably has hungry chicks back in the nest. Why did it decide to leave exactly now, and not earlier or later?
Now imagine you had a good view of the nest. What is the other parent doing? Are we sure that the two adults the two parents? How and why do they cooperate? How many chicks do they have – and what determines how many chicks they had? The chicks are all scrambling and begging noisily for food – why would they do this, surely it could attract predators?
If you could follow the same starlings over the whole season, or even until next year, you might wonder how many of the chicks survived until fledging, how exhausted the parents are after raising so many chicks and how this might affect their own energy and survival. And what about decisions like mate choice? Do the same parents stay together next year or do they find new partners? When do they do this? Do they sing – if so when, where and why? And when do they lay next year’s clutch? Do they also try to mate with birds other than their social partner?
Why nature works the way it works
Behavioral ecology seeks to answer these kind of questions. Behavioral ecologists have spent days, months or even years watching animals and wondering, and these questions would not have arisen if we hadn’t. It’s a set of questions that other biologists taxonomists, geneticists, population ecologists simply don’t consider. The questions do not need to lead anywhere; they are just about understanding why nature works the way it works. And quite often, they reveal amazing and important insights.
It was quite a revelation the first time someone discovered that they could use a mathematical model to explain what an animal was doing, and use it to predict what other animals would do in other situations. The model was about prey choice, and showed that in order to maximize energy intake over time, you should avoid spending time on smaller prey, and only eat prey above a certain size. They fit the model by observing handling time and measuring caloric content of different prey items, and found that a whole range of wild animals actually do what the model’s predicts. Though it may seem minor, this revelation in the late 1970’s was actually a breakthrough that prompted people to do similar research, applying formal models to a huge variety of animal behaviors. Thus was the field of behavioral ecology born.
Now obviously the animals aren’t performing complex mathematical calculations to determine which prey to eat or not, but the model’s success shows that they’d understood how ecology and evolution works to shape behaviors: animals behave optimally in a given situation, because those who did so in the past passed on more of their genes to future generations than those who behaved suboptimally.
Why does it matter?
Learning more details of animals’ foraging habits can help research in both population dynamics, community dynamics and species interactions, often with important consequences for conservation of endangered species. Mate choice and other reproductive decisions at the behavioral level of the individual has implications for evolutionary research at the species level, affecting reproductive isolation, speciation and phylogeny. Behavioral ecology has the potential to answer some of the biggest unanswered questions in biology. For example, nature is full of amazing examples of seemingly selfless acts of kindness, cooperation, even to the point of altruism (self-sacrifice). Behavioral ecologists have long used game theory to model such behaviors, and test the models by seeing whether they predict how animals behave in social interactions, depending on things like dominance status, group size, relatedness, hunger, experience or age. Explaining how such phenomena can evolve, and when they do and don’t, might even help us understand more about our own species, and how we can avoid our impending self-destruction…
But the real beauty of behavioral ecology is how it’s inspired from a true connection with the animals. For countless hours, researchers have sat and observed animal behaviors day in and day out. I’ve spent two summers on field work in the mountains of northern Sweden capturing, tagging and observing Arctic fox cubs on their dens, while counting birds, trapping rodents and analyzing vegetation in their territories to learn more about the needs of these critically endangered carnivores. Hard work but immensely rewarding, the most profound moments come after you’ve spent a few days at the same den, watching the same family continuously. At night, under the midnight sun, all alone in the mountains with the Arctic foxes, you see an adult run back to the den across the glacier with a ptarmigan in its mouth. You know why they run where they do, how they catch the prey, which of the playful cubs is going to get the first bite.
After all, how can we protect animals if we don’t understand them?