A huge percentage of the population shows some level of fear towards snakes, spiders and other "creepy crawly" animals. Because these fears are so widespread throughout the world, and throughout history as shown through cultural literature and mythology, it was long believed that this fear was innate. It was widely accepted that we were born with a basic fear of these animals because they can represent a significant threat to an individual human, especially an infant. It has even been proven that we are able to recognize these animals quicker and more easily than other non-threatening animals. However, a 2015 study may challenge our previous beliefs that infants are born with a basic fear of snakes.
Through an interesting set of experiments, scientists studied how infants and toddlers react to objects that people deem as "scary". In one particular study, they showed babies (as young as 7 months old) two videos side by side; one video was a snake, and the other was a non-threatening animal, generally an elephant. At the same time, the researchers played voices that sounded either happy or fearful. Perhaps not surprisingly, when listening to the fearful voice, the babies spent more time looking at the snake video, however they did not show any signs of fear themselves, such as an increased heart rate.
“What we’re suggesting is that we have these biases to detect things like snakes and spiders really quickly, and to associate them with things that are yucky or bad, like a fearful voice.” -Vanessa LoBue of Rutgers University Source
http://www.mirror.co.uk/news/uk-news/reason-babies-arent-afraid-snakes-11280259
In another experiment, three-year-olds were shown a screen of nine photographs and told to pick out some of the things they saw. More often than not, they identified snakes more quickly than flowers and more quickly than other animals that look similar to snakes, such as caterpillars. Interestingly, children who were afraid of these animals spotted them just as quickly as those who weren't, proving that we may be more adept at spotting these animals, but that ability isn't necessarily attributed to a fear of them. What the researchers discovered was that children did learn to be afraid of these animals more quickly and more easily, however the fear itself it not innate from birth.
There are only two fears we currently believe to be truly innate: heights and loud noises. Fears of things like spiders, snakes and the dark are what we call natural fears. Natural fears are learned at a young age, generally influenced by our culture and environment. Children build on cues from their parents and other close ones what to be afraid of and what not to be afraid of.
"You get evidence from your parents and your environment that you need to be scared of these things." -Seth Norrholm, translational neuroscientist at Emory University Source
So are we evolutionarily biased against snakes? Sure, we've come to recognize their potential as a threat and have evolved to spot them more easily. However, that bias is not a true fear, it just means that we are more likely to spot them when confronted. True fear of them is learned through either experience or loved ones, and while it may come more naturally than other fears do, the fact remains that we are not born afraid of snakes!
Article Link: https://www.psychologicalscience.org
