Yes, You Have a Homeostat
In which I make a strong prediction, of which I am perfectly confident, which is not true
Imagine that you're a wild animal.
And imagine that you're always hungry.
Sometimes food is scarce, sometimes food is plentiful.
Doesn't matter, you're always hungry, and you always eat whatever's nearest.
And as a result, you put on huge amounts of fat.
That's why you're eating, right? Storing up fuel for a rainy day.
And now you're carrying a huge amount of fat, so you don't move as fast as you did when you were thin.
What happens next?
(Seriously, think about it....)
(No no, you can do this, don't look until you've come up with your own answer)
You get eaten.
You've not only made yourself easy prey, you've made yourself valuable prey! You're full of fat! Yum!
What about apex predators? The few animals that don't have predators themselves.
They may not have predators to run from, but they have enemies, to run from or to fight. Usually other animals of their own species. Male animals fight all the time.
You lose those fights, maybe you die, maybe you just don't get the girls.
Either's a fail. You don't have descendants, and so you might as well have died.
Back to the drawing board, God.
Animal 2.0, he's never hungry. Doesn't even have a way to store energy. No fat on him.
Fast and deadly. Always runs away faster than the others, always wins the fights.
Sometimes food is scarce, sometimes food is plentiful.
Animal 2.0 goes short of food and dies. The fat animals can handle a few days, a few months of scarcity.
There's a *right* amount of stored fat. Different for different animals, different for males and females, maybe different season to season.
But at any given time, there's a right amount.
Animal 3.0, it has a homeostat.
Any given time of year, it's got a percentage of fat it wants to be carrying.
Not fat enough? Get hungry, eat whatever's near.
Too fat? Not hungry, ignore food, leave it to rot. You got better things to do than eat!
This design has some slight hope of making copies of itself, and so that's the design we see.
Animals need a way to keep their energy reserves at optimal levels.
If energy reserves are low, you’re vulnerable to shocks. A brief period where you can’t find food could kill you.
If energy reserves are high, you’re carrying too much weight. It’s crippling. You might not be vulnerable to starvation, but you can’t fight, you can’t run.
You can’t run from predators. You’ve eaten so much food that you’ve become food. Lots of food. Lots of slow, defenceless food.
You can’t fight your competitors. Animals fight a lot. Die a lot. An obese animal is soon to be dead.
Designing an animal which always takes on more fuel when it can is madness.
If you’re an animal with excess food available to you, you don’t put on fat. You find some other way to use it, or you leave it to rot.
That’s how you were designed to work.
We're African animals.
We don't hibernate, we don't store up fat for the winter. Where we grew up there is no winter.
The right amount of body fat for a man is 10% (more fighty)
The right amount of body fat for a woman is 20% (more resistant to scarcity, babies to feed)
Your homeostat will keep you there. No effort required. You got less fat than that, you get hungry.
You got more, you aren't interested. Leave half a pizza on the counter, maybe put it in the fridge.
That's how it works. That's how it's always worked.
Doesn't matter what you eat, doesn't matter what you do all day.
You stay the right weight all your life. You never need to give it a moments thought.