This morning, as I was walking to the supermarket, I passed by a large slug on the sidewalk. I thought about how easily someone who was walking by and didn’t look down could’ve easily squashed and killed it. A few moments later, I absorbed the fact that it was slowly sliding towards the road, and there, it was even more likely to face a death by accident.
Then I realized something: being good at avoiding humans is almost certainly a critical survival trait for animals. I don’t know the data, but I’m almost certain for all non-human animals greater than insect-size such an animal has killed far fewer humans than humans have killed them. From the intentional (hunting) to the directly unintentional (accidental squashing) to the indirectly unintentional (local extrema of pollution), there are just many reasons it is a bad idea for other animals to want proximity to humans.
(It’s also arguable whether insects can be considered to be killing animals if what about them kills is a disease that they carry, especially if the pathogen for the disease is itself alive. (Going even smaller-scale to things smaller than animals, it’s an even tougher question to ask what among things that a human does to bacteria can constitute “killing”. It’s fairly clear that cleaning one’s hands with hand sanitizer is killing bacteria, but if one consumes a food for which it turns out certain sorts of bacteria in the intestine are intolerant to, and then they die off, does that constitute killing?))
Doubtless there exist genes that affect an animal’s tendency to get near humans. In that case, animals that come into human contact are more likely to be selected against. Thus, when one thinks about it, when humans get to see wild animals, the ones they are seeing will tend to be more evolutionarily unfit ones. We would probably, from observation, underestimate the capabilities of other species because the smart ones will tend to know to stay away from us.