Humans translate into conscious thought and decisions the impulses that are common to most mammals: sex, food, parenting... We view these thoughts and decisions as being the products of our own volitional thought processes (and in some ways they actually are), but we often arrive at the same decisions an animal would make. Procreate with the most viable mate we can find, eat the tastiest food, do what we can to make sure our offspring make it to adulthood.
When we see animals making such "decisions" and taking actions like caring for their offspring, we say to ourselves, "aw, how cute, the mommy wants her baby to be strong and happy someday, just like what we want for our children." But it's not that the animal is similar to a human; it's that the human is actually still an animal.
"Dad, what do you think about all the time? You're always thinking all the time."
"Ohh, all kinds of things."
"Oh, about the rain, and about troubles that can happen, and about things in general."
"Oh, about what it's going to be like for you when you grow up."
"What's it going to be like?"
"I don't know. It's just what I think about."
Animals mindlessly eat and hunt and have sex and run away from predators and protect their young. The only reason why evolution made it so that we eat and hunt and have sex and run away from predators and protect our young is because our genome wants us to create another copy of it that will do the same. And that fact doesn't make our lives sad or any less meaningless; it is what creates the context for us to be happy and seek meaning in our existences.
The above quote is from Zen and the Art of Motorcycle Maintenance (Robert Pirsig), page 202 of the 1984 Bantam edition.