I hate poachers and I love animals, but this guy I hard not to love and he does make a good villain. Utterly cruel and psychotic, he loves killing and is greedy. In fact, he's so psychotic that he attempts to feed Cody to the crocodiles when he no longer has use for him.
The first is leptin, which is a hormone secreted by your fat cells that acts as an appetite suppressant. Leptin levels peak when you fill up on food. So, when you eat a lot, your appetite goes away. If you ever said, 'I am so full I couldn't eat another bite,' then in that moment, your body was flooded with leptin.
Obese people have plenty of leptin, one of the reasons they're fat is because of leptin RESISTANCE in the brain. Here's how it works. Since leptin is an appetite suppressant, your brain needs it as a signal that it's full.