I actually wonder how animals like sea turtles or fish know what to eat...They are not raised or taught by their parents, so is it just trial and error? What stops them from eating poisonous stuff ?
I can offer a example of bird. seem like the toxic butterfly just let birds feel terrible, so they actually learning from trying different butterflies.
warning colors work well. birds don't want to eat distasteful butterfly again. so even just looks like distasteful, butterfly still can enhance fitness.
at least this is a good deal all butterfly have same color...
Your epigenome (the sum of the external changes made to your DNA) affects your DNA with time, and some of these changes are even carried over to your offspring.
Behaviours can absolutely be learned and hardwired, given 1000s of years
As someone mentioned above, a deer is not born with random weights on its NN