Many people appear to believe that humans are somehow separate from animals. It seems important for some to believe that. Clearly, though, we are all products of evolution. Understanding what connects other mammals and vertebrates to us is an important thing that distinguishes some people from other people.
With mammals, particularly, we share almost everything. We have similar skeletons, reproductive systems and even brains. And yet, many of us believe that we are hugely different from other mammals. We need to believe that, it seems. We see other primates, even, and do not observe what makes us part of the same group of mammals.
In many ways, religion has played a large role in our continued belief that we are "superior" to our fellow mammals, in particular, and to other lifeforms in general. For some, denying even evolution is a way to maintain that belief. It requires serious avoidance of observation and thoughtful contemplation to hold such a belief, I think.
It's a shame, since there is much to learn from close observation of our related species. That's why I posted this OP. It is good for us to ask such questions after observation of events like I described, or even as we pet our dog or cat. The answers can be revelatory.
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