If you love centuries-old unsolved  science mysteries, pull up a chair.

If you think the biggest thing ever  is the coolest thing ever, buckle up. And if you can’t get enough of kids  being the heroes we don’t deserve, then settle on in, because this video has it all.

Basically, it all starts  with some really mysterious, possibly-dinosaur bones that  stumped researchers for decades. And it turns out what we needed was  an 11 year old walking along the beach to find more of these bones  for researchers to figure out what the heck they’d been  looking at for all those years. The answer is huge news.

In every sense of the word. [♪ INTRO] Let’s get into the meat of the story. Or rather, the bones. Since the 19th century, paleontologists  had been finding these weird bones from the late Triassic Period  that didn’t quite fit in with the bones of other animals from back then.

So researchers literally  called them “mystery bones.” They’ve been trying to figure out  who these random bones belong to, with the frontrunner theories being  some sort of amphibian, dinosaur, or some other reptile like plesiosaurs  or ichthyosaurs or something. The bones seemed kind of dinosaur-like,  mainly because of how huge they were, since researchers didn’t know of any marine  creatures that were this honkin’ big. But the problem with that idea is that  we don’t know of any dinosaur species that lived in the water full-time, which makes it pretty unlikely that this is actually a dinosaur.

And aside from their size, there  was a lot about these bones that just didn’t look very dinosaur-y. Like, they were missing an outer layer of bone that you’d expect to see on dinosaurs. Sometimes we can't get all  the information we need from just the shape of the bones.

In those cases, we can turn to their  internal structure to see how they’re formed, which can give us even more insights  into what these animals might have been. And these bones had these collagen fibers that were distinct from  what’s usually found in dinos. They’re woven together into a unique matrix  that goes along the length of the bone.

Some animals’ bones have a kind of  organized, criss-crossy structure, and others have just parallel  grooves going up and down them. But this mystery bone was somewhere in the middle, with fibers that sorta criss-cross,  but not in a very organized way. Another weird thing about these  bones is their growth lines.

In dinosaurs, these lines won’t show  up until that animal is mostly mature, but these bones have growth lines  despite being from a fairly young animal. Now, the third mysterious quality of  these bones might be the most complicated. And the details of exactly how they’re  different could fill a dissertation, so I’m just going to say that these bones grow in a totally different way from other animals.

Basically, your bones grow new tissue  internally to replace older tissue even after they’ve reached full adult  size, which is called remodeling. And from the evidence these researchers found, this animal’s bones remodel in a way  unlike anything else they’ve ever seen, which they suggest has to do  with the bones’ wonky layers. Not only that, but the veins run in  a different pattern within the bones, which would mean that their  blood flow to their bones was different from most other  fossil animals we know of.

Which means there are a lot of reasons  to be confused about these bones. None of these traits match up with any dinosaurs that researchers have ever found. And researchers have found  a lot of stinkin’ dinosaurs.

And they’re also not characteristic  of the dominant land vertebrates of the early Triassic: our  ancestors, the synapsids. But they didn’t match up with any  known non-dinosaur reptiles either. The animals they most seemed to  match up with were a giant version of ichthyosaurs, which were aquatic reptiles  that were also around in the Triassic.

But even then, it wasn’t a 100% match. So maybe these bones belonged  to some new kind of ichthyosaurs that are unlike any we’ve seen before. But that’s the kind of claim  that you need more samples, and really good samples, to confirm.

Cue 11 year old Ruby Reynolds. Back in 2020, Ruby was walking  on the beach in Somerset, England with her father when they noticed a  fossil that someone had left on a rock. So the two of them searched the  nearby area for more and ended up finding an even bigger bone  that was from the same creature.

They had stumbled upon a 202  million year old fossilized bone that was from the same time  period as those mystery bones. But this unlikely paleontologist duo  didn’t stop at just finding one bone. They looked up what animal the  bone might have belonged to, and accurately identified it as a giant  ichthyosaur, like those mystery bones.

Because, get this: it had  all of those weird qualities that the other mystery bones had. When they got in contact with  researchers who had described giant ichthyosaur bones a few years earlier, they all went back to the beach  together and found even more bones that they concluded were  probably from the same animal. And that just goes to show you  that you don’t have to have a fancy degree to notice when  two bones look like each other.

Like, this discovery was HUGE for paleontologists. Not only do these bones give us  more insight into our mystery bones, but researchers were able to show that they represent a brand-new genus and species! So this 11 year old found  evidence for a new kind of animal!

Okay, so it’s a really old kind of animal. But it’s new to us! See, the most similar-looking bones  to these came from Canada and China, and were 13 million years older.

So it’s unlikely that they’re the same species. And technically, Ruby’s original  find was the second bone discovered with this look to it, from the same  time and location as the first one. But hers was much bigger and better preserved, because the earlier bone was broken in 5  places and didn’t fit together that nicely.

So it wasn’t until they had  Ruby’s bone that researchers were officially ready to  declare a new genus and species. They named it the Ichthyotitan  severnensis, which is Greek for “giant fish lizard found in the Severn Estuary.” And, I mean, if you get a  chance to name an animal, “giant fish lizard” is a great choice. Kudos on that one.

With the word “giant” in the name,  you’d probably expect a big animal. But this guy was really giant. Ruby’s bone was dated back to a time  when a lot of big guys were popping up, like non-avian dinosaurs and crocodilians.

And, at least in the oceans,  Ichthyotitan severnensis blew pretty much all of them out of the water. Well probably not literally, but you get the idea. Now, humans weren’t around  to see the big guy in person, but there were a few clues that researchers  used to get an idea of its size.

The bone that Ruby found was the hinge part of the jaw, called the surangular bone. It’s not even the part where the teeth go  and it’s already more than 2 meters long, which is way bigger than any other  ichthyosaur surangular bones. And if the surangular is over 2  meters, they could estimate that the rest of the body is probably  around 26 meters long, which would be a new largest  body size for an ichthyosaur, measuring almost as big as a blue whale.

But it might actually be bigger than that! The microstructure of the bone  suggests that the animal could have still been growing upon its  demise, so the fully grown reptile could have been over 30 meters long! And since the previous record-holder  for largest ichthyosaur was just 21 meters long, this new species is  now the largest we have ever found.

The researchers trying to estimate  this reptile’s size said that basically all of the ways that giant ichthyosaurs’  bones were different from other animals, like their mysterious cartilage,  growth patterns, bones, and veins, were the adaptations they’d needed to get so big. So all these researchers aren’t  saying that all of the mystery bones are from this new kind of reptile, but they have a lot in common and are probably distant cousins. At this point, there seems to be a consensus that the mystery bones belonged to ichthyosaurs.

So the next time you’re hanging out at the beach, maybe keep an eye out for any stray fossils. You might just solve a paleo-mystery. [♪ OUTRO]