So?
We kill animals all the time, usually with little or no remorse. What distinguishes us from other animals? We think. When a kid thinks, it becomes a valuable human. Until then, it's a lower animal.
We kill animals for food, the species will do what it can to survive. Some hunt for pleasure, although this is a small minority of the population. Like most animals hunt for food, not for mere sport.
Nearly all creatures, like humans, take care of their young, it is a natural process, almost a 'natural law'.
All animals think to some degree. Otherwise they would not be able to survive or adapt to their environment throughout the ages. The differece lies with a sentient animal. Aware of its existence, but able to also ponder its future, question everything around it, build, learn grow, expand, survive another way.
Saying that a human is a lower animal until it thinks is a very dangerous philosophy. Once you set that bar, it would slowly rise. Your idea of a 'valuable human' has similar structures and educational thoughts of the infamous doctors working for Hitler's Germany. Once we start to demean a person, we demean all of us.
