Are fish afraid of snakes?

That is why the fear of spiders and snakes is normal

Is the fear of spiders and snakes innate? This is what scientists from the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig and the Swedish Uppsala University wanted to know - and have carried out an informative experiment.

Learned or innate?

The scientists divide this into two camps: Some believe that this fear has been learned - for example, copied from parents. Others think the fear of spiders and snakes is innate.

The researchers have now been able to substantiate this second thesis with an experiment - with six-month-old babies. The reason they chose subjects so young: Babies haven't seen that much.

The likelihood that a six-month-old baby picked up spider fear from someone else is very small.

Stress reaction in spider photos

The researchers showed the babies photos of spiders and snakes, but also of flowers and fish. All pictures were the same size, had the same color and were illuminated in the same way.

The scientists wanted to find out whether the babies react differently to the images. Indeed, they were afraid of the spider and snake photos.

The researchers were able to demonstrate a direct physiological fear reaction in the babies: They had enlarged pupils when they saw the images of spiders and snakes.

This suggests that a region in the brain was particularly active where norepinephrine is produced. And that causes stress. With the supposedly harmless flowers or fish, the babies did not have this reaction.

Afraid of spiders, but not afraid of bears

It is known from previous studies that babies do not associate images of rhinos, bears or other supposedly dangerous animals with fear.

The Leipzig researchers believe that the special fear of spiders or snakes is related to the fact that potentially dangerous reptiles and arachnids have coexisted with humans and their ancestors for 40 to 60 million years.

And thus significantly longer than with the mammals that are still dangerous to us today, which have not been around for so long. The reactions to spiders and reptiles such as snakes could therefore anchor themselves in the brain over a very long evolutionary period.