What is rescue behaviour?
Author: Rachel Cooper
Artist: Laila Kandil
Editor: Emily Vialls
A common occurrence in humans, but extremely rare in animals, rescue behaviour is shown when an individual is in distress, and physical harm will come to them if they don’t escape the situation. Another individual acts to help, putting themselves in a dangerous position even if no immediate benefit will come to the rescuer. This behaviour in non-human animals has so far only been demonstrated in a small handful of species, so the full extent is vastly unknown. It is nonetheless a significant discovery which leads us to question, why? Isn’t deliberately risking their lives to save others going to hinder their own survival rate? Or is it possible that an evolutionary development of empathy could increase the species’ chances of survival as a whole?
There are a handful of cases of species presenting this behaviour, across different animal groups. One example was shown by the removal of sticky ‘bird catcher tree’ seeds by a group of Seychelles warblers. These species can become caught in seed clusters of Pisona trees (also known as bird catcher trees); the seeds attach to their feathers, weighing them down and preventing flight which may cause mortality. In some cases, Seychelles warblers were observed removing the seeds from other individuals in the group, even if it meant they risked entangling themselves. Another observation involves an adult female wild boar rescuing two younger boars from a wooden cage trap. It captured the adult boar removing logs that sealed the cage door, allowing the juveniles to escape. The trapped boars had shown clear signs of distress such as charging at the cage walls, and the adult female put herself at risk by spending a significant amount of time at the site of the trap during the rescue. In a study of elephant behaviour, a case was recorded of an adult elephant removing a tranquiliser dart out of another adult male.
Empathy as an evolutionary trait
The question hereby presents itself whether or not these incidents of rescue behaviour were driven by empathy. This ability to recognise and respond to emotions that other individuals express is a behaviour which has been integral for human evolution. Our species has dominated the planet, with the main attribute of population success being our highly complex brain development. We evolved empathy to facilitate cooperation, improving the survival of individuals, and by extension the population as a whole. It is hypothesised that selective pressures aided this evolution. early human ancestors had to develop strong teamwork to survive in their small numbers. They had to compete for resources, find shelter and avoid numerous predators. Without many physical adaptations, we benefited from helping each other, resulting in the development of empathy.
So could this same idea apply to animals? In the theory of natural selection, species evolve and pass on traits that aid their ability to survive and reproduce. Traits that aren’t useful wouldn’t be passed on as successfully, and considering rescue behaviour puts individuals in dangerous situations, this is surely unbeneficial to them. Despite this, there is a case to be made for strength in numbers. Maintaining the survival of a group could benefit reproductive success due to a larger gene pool. In the case of the warblers, all four cases of rescue behaviour were recorded between members of the opposite sex, indicating there is some truth to this theory. Recent research suggests that animals are capable of displaying empathy, particularly dogs, and we now often use them in therapy because of this. Despite little to no evidence to confirm that the rescuers understood the victim’s emotional distress aside from the obvious physical distress, it has been seen in the case of the wild boar. The rescuer female presented an arched back and raised mane in the photos, a sign of stress response. This could imply she recognised the emotional state and was able to empathise with it, motivating her rescue behaviour.
Discovering that animals display rescue behaviour, perhaps stemming from a development of empathy, gives us an idea of their evolutionary potential to ensure collective survival. We shouldn’t underestimate the capabilities of animals, and since they are put under more and more stress by human actions, there is heightened pressure to adapt to changing environments. We may see further displays of rescue behaviour, along with new survival strategies, as their brains evolve and develop to catch up.