Why is the life of a Zimbabwean citizen more important than the life of a Zimbabwean lion?
The fact that that's a question that was even asked is shocking, and honestly disgusting. Yes, people are more important than animals. To imply otherwise is downright idiotic.
You have a fixed belief that any and every human life is more important than all animals or plants.
You may be referring to some concept of intelligent self-awareness, but you need to be more clear as to what it is to evaluate whether its a real difference between humans and lions; lots of animals have demonstrable self-awareness of various forms.
I agree that the human condition is more important, but I don't think your explanation of why holds up.
I'm not talking about higher-order intelligence, I'm talking about sentience -- the ability to experience.
It is rather simple now to find a program that would defeat the original formulation for a Turing test, but no one would describe them as having consciousness.
However, I believe it very possible that humans are doing much the same thing with a sort of sentience Turing test that we project onto animals. They _seem_ to have experience, because they react to stimuli. But the same is true of the computer.
We know that creatures with basically nothing in the way of a brain, take earthworms or severed octopus tentacles, will react to pain, hide from it.
We also know that pain has two parts -- a conscious experience, and an animal aversion. This is made clear by the existence of Pain asymbolia, where a person gets damage to the insular cortex (a lower part of the brain), and is no longer averse to pain, despite reporting that they still experience the pain just as they did before the injury.
I believe it quite likely that consciousness exists in the human brain alone, and is of very recent evolutionary vintage, evolving in conjunction with language. That when humans project sentience on their pets they are basically falling in love with a biological automaton, no different from a person falling in love with a chat-bot.
Unless we find a reason to believe that mere programming couldn't account for the behavior of animals (which seems increasingly unlikely, as our own rather rudimentary robots advance), it seems much more likely that evolution would have evolved the simple instinct system first -- only adding consciousness later on when it became an evolutionary necessity, as could have been the case for complex communication about qualia.
This speciest emphasis on human-like features as criterion for value shouldn't be dominant in the first place.
Ability to feel pain?
Scarcity? [In the sense that there are 7 billion people and only 5000 tigers, so we should focus on saving the tiger?]