There's a screenshot I've seen a few times over the years, of part of a Tumblr or reddit thread. I've spent the past half hour looking for it, with no joy, so I probably have some details wrong.
The first part, someone comments about someone who got injured and broke the part of his brain that controlled yawning so he just kept yawning for years. And then someone comes in and says something like, "Wait, what - you're telling me that the default is YAWNING = YES and we have a specific mechanism that says 'No, don't yawn this moment' and it does that constantly?!" And ... then there's a third part where they talk about sharks or something? Like I said, I can't find it right now :(
Sharks are about 450-400 million years old. They were around 200 million years before the dinosaurs, and have outlasted them by 65 million years. They're older than the North Star, the rings of Saturn, the Atlantic Ocean, and trees.
And it took 60 million years for the trees to start rotting when they died, because the bacteria to break them down didn't exist. Those trees died, fell over, became peat, and then eventually coal. The trees that were dead and buried trapped carbon dioxide that had been in the atmosphere. 90% of the coal we burn today comes from the period when trees didn't rot, and we're re-releasing all that CO2 back into the atmosphere, from where it's been safely sequestered for 250 million years.