S.E.T. School: Fossils and prehistoric life!

Since we didn't spend much time on the fancier fossils, here's some examples:

This guy is one of the first creatures to figure out jaw structure and teeth. It doesn't have individual ones. Instead, it's grown a massive, massive jaw that has a jagged edge.

The quality of a fossil depends on many things. Look at this amazing fossil.

In addition to how incredibly fine the rock grains were, this fish must've been buried immediately after death while mostly undamaged. That's why the fine tissue was preserved.

This is a very important fossil. This fossil is of a marine reptile, which for a long time were believed to crawl up onto the beach to lay eggs despite the fact many of them had body types that didn't seem able to do it. But they were airbreathers, which means they couldn't lay their eggs in the water or the fetus within it would drown. Here, we see what appears to be one who died while giving birth, meaning they gave birth to live young instead.

Here's another fossil showing the great detail you can find in stone if it's just the right kind.

It's a sea spider from the Devonian era. Sea spiders, despite looking like spiders, have a whole bunch of weird traits and are clearly only loosely related, leaving scientists incredibly confused about what they were related to and if they evolved from more conventional spiders to add those weird traits or if they were really primitive and had the weird traits because proto-spiders all did, but the rest lost them. Read more on Wikipedia, they're great.

Some definite insect fossils:

Look at this! Wings evolved surprisingly early in history.

And here's a sea scorpion.

And below is the fossil that first made people realize dinosaurs could have feathers. It was discovered in Germany, in particularly good limestone.

Let's wallow in the oceans some more.

Or maybe we could not wallow! Maybe we could frantically try to swim away to try land and then run and never stop.

No? You insist on more? Why?

This guy is an example of how very hard it can be to reconstruct animals from fossils. Unlike a lot of those gorgeous fossils, we mostly have the teeth of this one, which were in this spiral shape. Currently, scientists believe instead of it having the teeth externally in a sort of razor-toothed tongue/tentacle, the spiral was internal and allowed it to have a similar constantly regrowing teeth thing going on as the modern shark. The smaller teeth would be in the center of the spiral, and as they grew, they would move upward until, at full size, they reached the animal's mouth, then were torn out by struggling prey or fell out on their own to be replaced by fresh teeth.

Did I mention the horrible fish with the giant jagged bone jaws is gigantic? It is dunkleosteus, osteus meaning bone because they are solid bone, and it is absolutely gigantic.

The only consolation I can offer is that with those huge teeth, it may have focused on larger prey than your tiny, helpless body. Or maybe not. We don't know.

This shark is extinct. While this may seem terrible, it almost certainly wouldn't have bothered you, because it was busy devouring whales. It might tear open your boat and cause it to sink, but it probably wouldn't eat you afterward! Something else would.

You may know this one as the Loch Ness monster. From what we currently know about this general type of animal, its long neck was not like a swan's bendy one but stiff, although we aren't sure how much. It also does not appear to have the muscles to raise the head above water like that.

There's very low visibility in water, so the current theory is that its long neck meant its prey couldn't see how massive it actually was in time. They'd only see the tiny head and think it was a small fish.

See this guy? He's the size of a schoolbus. Look at that friendly smile!

Remember the Permian extinction? This enormous thing shows up shortly AFTER that extinction (a mere eight million years!). Scientists are very interested. One possibility is that it's one of the animals that can function normally at a low size, including reproducing. A few of the tiny ones squeaked by on whatever tinier things they could eat, having babies who squeaked by in turn, then when conditions improved, they were ready and able to grow to their horrifying, horrifying size.

We don't even know their max size was schoolbus. It could be the even bigger ones didn't fossilize.

In conclusion, if anyone says, "Wanna go in my time travel machine?" the answer is obviously yes, but don't go in the water. Tell scientists that you've about to go to the past in a time machine and ask to borrow a robot camera to dump in the ocean instead.

On a less scary note, can you figure out what real fossils these guys were inspired by?