When I was younger, I loved catching lightning bugs (you might call them “fireflies,” but the common term ’round these parts is “lightning bugs”). Pretty much every kid does, if they live in an area where they emerge around dusk. They’re magical.
I was a fairly inquisitive kid, and one thing I knew about when I was around 8 or so was the relationship between a creature’s survival and the various ways that creature competed for that survival with the other creatures in its ecosystem. I knew that all living creatures had to have some evolutionary advantage in order to survive – it had to be fast, or strong, or poisonous, or armored, or camouflaged, or whatever.
So one day I asked my dad: “How are lightning bugs still around? They don’t sting or bite, they’re so slow that a human kid can catch them easily, and they actually advertise where they are. They seem like they’d be the easiest meal for any predator, ever. What keeps them alive?”
And my dad laughed. He said, “Go eat one.”
Apparently, the goo in their butts that makes them flash tastes absolutely horrible if you eat it. Our dog had eaten one when it was a puppy, and my dad had watched for the next 45 minutes as the dog hacked up the taste, chewed dirt, and even licked the sidewalk in an attempt to get the cloying, abominable taste out of its mouth.
So that was the lesson – some things are poisonous, or armored, or camouflaged, or speedy, or whatever as a way of defending what they have. So if you see a creature that has none of those things, then chances are good that the creature doesn’t have anything anyone wants.
That’s true in the world of humans, too. If you’ve ever looked at a deal on some product or service and thought “wow, that deal is so amazing, I can’t believe there’s even any in stock” – remember the lightning bugs.