A new published study in the journal Proceedings of the Royal Society B suggests that having a larger brain does not always translate to better survivability for animals as what was initially thought.
Scientists have identified several factors that contributed to the death of certain species during the sixth mass extinction event. These are fractured habitats, pollution, over-hunting and climate change.
New research conducted by wildlife biologist Eric Abelson of the U.S. Forestry Service, however, found that the relative size of animals' brains could potentially play a larger factor in their demise.
While a cause-and-effect regarding the finding is yet to be determined, it could help animal conservationists come up with more effective strategies to identify animals that are more at-risk of extinction compared to others.
The Evolutionary Advantage Of Having More Brain Matter
The findings of the new study contradict the earlier belief of scientists that species with more brain matter maintain an evolutionary advantage over other creatures. Having a larger brain is thought to correlate with a cognitive edge, such as being able to survive in a new environment.
Abelson, who carried out the study while serving as a doctoral researcher at Stanford University, pointed at the ability of animals to thrive in colder climates despite not being able to grow dense fur. They would use their problem-solving skills to overcome the situation, either by constructing a warmer habitat or spending more time in the sun.
These creatures, however, would then have to eat more or use up fewer calories doing other tasks so that they can devote their energy to growing and supporting neural tissues.
This tradeoff could cause these larger-brained animals to suffer from other life-threatening factors such as a scarcity of resources. This is because the size of their brains could also make them less likely to adapt to certain situations such as living in polluted waters for aquatic animals.
Abelson measured the relative brain size of hundreds of living mammals and then compared the results to those found in the International Union for Conservation of Nature's lineup of endangered species.
He discovered that the mammals that had larger brain sizes were more susceptible to threats of extinction. Creatures that had smaller bodies, yet relatively bigger brains appeared to be more endangered than any other species on the list.
Abelson said that his findings are just a preliminary to understanding the impact of relative brain size to the vulnerability of certain mammals to extinction. He said that additional studies are needed to explore this potential relationship even further.
Photo: Rod Waddington | Flickr
