Of course it is learned, and fear is triggered by anything unfamiliar, that causes a high reconstruction error. Because it means you don't understand it, and it could be dangerous. We are just not used to encoding anything so deep below the eye level, and it freaks us out.

Do you really think every single ant is learning all that on its own? And if ants can store that in their DNA, why don't you think other animals can? DNA works just fine as generic information storage, there are obviously a ton of behaviors and information encoded there from hundreds of millions of years of survival of the fittest.