so the megalodon is most definitely extinct? how do scientists know?
well, the thing about large predators is that they leave an impact on an ecosystem big enough that you can tell they’re there, even if you never observe one directly. in this case, we know they’re definitely extinct because of the behavior of whales! whales used to max out at about 50 ft long and were fast and agile, entirely because of predation by megalodon!
but about 2 million years ago, our whales began to rapidly increase in size until we ended up with real monsters like the blue whale. this pretty directly lines up with the extinction of megalodon, and the removal of the pressure they were putting on large whale populations.
basically, large whales can get away with being gigantic, slow tanks in the oceans today because there simply isn’t a predator big enough to take them on anymore. if megalodon still existed, we would be seeing its impact on whale populations! whales would be smaller, and a hell of a lot more skittish than they are.
everything in a given ecosystem is connected, and you can often get important information about the unknown parts by observing the behavior of other parts of the ecosystem.
All this, and the fact that if the ocean had sharks as big as Megalodon and had enough of them to sustain the species at all, we would have found at least one Megalodon tooth washed up on a beach somewhere that wasn’t fossilized. More likely, we would have found hundreds of such teeth every year for as long as we have existed. “We didn’t know giant squid existed!” is a common argument I see from cryptozoologists, but it’s also flat out false. We did know. We knew there were giant squid for centuries because we found remains of them for centuries. We simply hadn’t captured or filmed a live one!
Okay, so I am well aware that this isn’t at all how evolution or natural selection works, but I still want a horror film that begins with a pair of scientists with dramatic music playing in the background as they pour over piles of records, until one of them turns to the other and says “it’s the whales. They’re becoming smaller, and more skittish.”
The other scientist looks out the window, over the sea. “Mother of god,” she whispers.
Alternatively;
We begin to find giant shark teeth washing up on shore. People freak out. “Scientists find evidence megalodons never went extinct!”
Then the lead scientist calms everyone down so they can explain. “No. It’s worse than that. If they never went extinct, we would’ve found evidence like this before now. This means… ” Dramatically takes off glasses.
“They’ve just come back.”
“But they can’t just suddenly come back like that!”
“You’re right. Someone brought them back.”