It’s the end of 2024, so you know what that means.

It means that it’s time for us to talk about all the biggest and coolest fossils that were announced this year. And of course, that means we have some absolute GIANTS to talk about … But don’t forget about the little guys!

Oh hey, it’s Kallie from Eons! I guess you just heard us talk about fossils and showed up? Pretty much, yeah.

Anyway, I hear you’re excited about the big jaw-dropping fossils, but it’s not just the giant fossils that tell us a lot about life on Earth. There’s a lot we can learn from the little fossils, too! OK Sure, the big ones just seem Cooler, to me Okay, how about you talk about your favorite fossil giants of the year, get it out of your system, and then I’ll tell everyone about something smaller that’s just as cool?

Works for me! That means I get to talk about the cooler fossils [intro] So, you might be familiar with the biggest fossil snake ever found, the Titanoboa, which existed around 60 million years ago in the neotropical forests of Colombia, in South America. But there is a chance that a new fossil snake may take that crown, at least if we’re going by tip-to-tail measurements, from a snake that existed about 47 million years ago.

This new snake, Vasuki indicus, was named for both the mythical Hindu snake around Lord Shiva’s neck, And for India, where it was found. It’s in a group of ancient snakes called madtsoiids. They’re kind of similar to today’s pythons and boas, based on the fossil vertebrae that were found.

And Vasuki probably used a similar feeding strategy to the modern relatives, ambushing and constricting their prey. They found a total of 27 vertebrae, which researchers used to estimate that Vasuki was somewhere between 10.9 and 15.2 meters long! I was upset when I thought that might be feet But it was meters We think that Titanoboa was somewhere between 13 and 14.3 meters long, so it’s possible that Vasuki blows them out of the water.

Titanoboa was probably still the heavyweight champion however, and that’s because of where they lived. Because Titanoboa lived in water, they had buoyancy to help support their weight. All 1.27 tons of it.

And even though they’re not quite as huge, modern day green anacondas use a similar strategy to help manage their massive weight. But Vasuki had slightly smaller vertebra dimensions than Titanoboa, so even if it was longer, it probably wasn’t as heavy. On top of that, this fossil was found in what was likely a back swamp, meaning it was an area that would flood periodically, but it wasn’t fully aquatic all the time.

This suggests that Vasuki probably spent a fair amount of time on land, like other Madtsoiidae and modern-day pythons. A discovery like this is not only cool because of the snake itself. These types of fossil finds can also tell us about the climate at that time.

Snakes don’t have the ability to maintain their own body temperature, and rely on the surrounding environment for their body heat. So the bigger that snake body, the hotter the air needs to be to sustain it. Which is why we think the average annual temperature during Vasuki’s time was a balmy 28 degrees Celsius.

So this enormous fossil find not only revealed a previously unknown snake of unusual size, but also a bit about what the climate was like too. This next monster takes us down under, to Australia. Because of course that’s where some of the giantest, weirdest fossils would be from.

Around 50,000 years ago, massive kangaroos, carnivorous lion-like marsupials, and other bizarre behemoths roamed the continent. But there was one avian giant whose fossils had been tantalizingly hard to track down. This mega bird was estimated at over 250 kilograms, and over 2 meters tall.

And the thing is, researchers have known about it for over a hundred years. As in, the first fossils of it were dug up in the late 1800s! The only skull they’d ever found was badly distorted, which meant there were a lot of things we couldn’t know about these massive birds.

Like, who they were related to. At the time, researchers thought it was related to emus and other flightless birds. Which makes sense But without more skull bones, it was hard to know for sure.

But in 2024, researchers announced that they’d found a fully complete skull, as well as several partial skulls. And these new bones showed that the mega-bird wasn’t an emu at all, and was in fact a distant relative of water fowl. Which inspired them to give it the greatest nickname there has ever been.

Giga-goose. They could even tell that it had a very strong goose-like bite. Ouch.

And coming from a 500 pound goose, that's extra ouch. These giga-geese had specially adapted ears to keep water out too, like modern water fowl. Which means they were at least somewhat aquatic.

While it’s not exactly clear why they went extinct, I’m pretty happy they did, one hypothesis though is  that it was all about water. See, these giga-geese needed giga-puddles to splash around in. As their home range became more arid during the middle Miocene, the wetland habitats That they relied on basically all dried up.

Which may be for the best, since I’d imagine that a giga goose makes giga poops, and I wouldn’t wanna have to deal with that I also, am scared enough Of normal sized geese Our next giant fossil is also a dinosaur, but the not-avian kind. If you know even just a smidge about dinosaurs, you could probably recognize a Triceratops. And while Triceratops are pretty wild looking in their own right, some dinos in this same family, the Ceratopsians, took that signature frill and horn look and got really funky with it.

Like this new guy! It’s named Lokiceratops rangiformis after the horned-helmet wearing Norse god of mischief, Loki. And it’s an appropriate choice, given that this dinosaur has some of the largest frill horns of any species found in the Ceratopsian family to date!

This dino was roaming around about 78 million years ago, and have i mentioned, it was very big? Lokiceratops is estimated to have been at least 20 percent larger than its close cousins the Medusaceratops, who are lumped together in a large group of Ceratopsians called the Centrosaurines. And its head alone is just under two meters long, making our new friend Loki easily the largest centrosaurine ever found.

This discovery is extra neat given its location. And not just because it was found here in Montana, where I am right now. But of course, we love that too.

Shout out to all the Montana dino hunters There were already three known species of Centrosaurines from this region, and finding a fourth was a pretty big deal. See, it’s really rare to find so many closely-related species of dinosaurs all living in the same place at the same time. It means that this group of dinos all went through rapid evolutionary changes and species splitting.

Not only that, but since the main difference is in the horn and frill stylings, the researchers even suggested that the species splitting may have been driven by sexual selection. The idea is that those fancy horn variations would have been selected for by choosy mates, which speeds up the process of species diverging into wildly different forms. Regardless of what drove these Centrasaurines to diversify so much in such a small area, the discovery of Loki has really helped give us a better picture of the complexity of this ancient Montana ecosystem that used to be in our backyard, those 78-ish million years ago.

This scishow video is supported by the presidents of science, McClaren Stanleny and Charlie Stanley Once again these incredible patrons have chosen to make this video free for anyone and everyone to watch. So as long as you have internet access you can learn here on SciShow. And selfishly I am thrilled to have them as our benevolent presidents because they also help pay for us to do this.

So if this video is worth anything to you, let us know in the comments, or at Patreon.com/SciShow We have one more dinosaur to talk about today, and it’s not too surprising that you may not have heard of them. Because they’re pretty… underground. Not just that the fossils were found buried That is usually the case As in, these guys hung out underground.

In burrows. We’re talking about a new species called Fona herzogae, which was discovered in Utah. It dates to the middle of the Cretaceous period, 99 million years ago.

And these dinos appear to have spent at least some of their days snuggled up underground. They were about a meter and a half long, and had some interesting adaptations that hint at their burrow-building abilities. Things like their small but strong front limbs paired with beefy back legs, and a fused pelvis that  would have provided strength and stability when digging up a storm.

All of those are things that modern burrowers like jerboas and kangaroo rats, have too. These guys are among the only vertebrate fossils found in this particular geologic formation in Utah where their bones are found  not only fairly complete, but more or less laid out in the right spots, looking like a well put-together skeleton. But the skeleton fossils of other species found in this area tend to be spread out, and not so complete.

And this may not be a fluke, because if they did spend a lot of time underground, any of them that died in their burrows were already more or less buried, increasing the odds of fossilization. Since several of these dinos were found all together and really well preserved, it seems likely, even if we don’t have any direct evidence of the tunnels or burrows themselves. So it turns out that these dinosaurs’ habit of taking underground naps helped preserve them for future paleontologists to dig up, tens of millions of years later.

Just another case of something only becoming mainstream when they’re already dead. Those are just a few of the coolest giants discovered this year, but in the spirit of fairness, let’s let Kallie make a case for the little guys. Take it away, Kallie!

Thanks Hank. Let’s talk about this brand new, itty bitty creature that’s shaking up what we know about a whole  branch of the tree of life. What can a 520-million-year-old worm-like larva the size of a poppy seed tell us about the evolution of spiders, insects, and crabs?

Well, a lot more than you might think. These critters all belong to a group called ‘euarthropods,’ which also includes the extinct trilobites, horseshoe crabs, and centipedes, to name a few. This group may be the most numerous and diverse phylum of animals on the planet, living basically everywhere, from the ocean to freshwater to dry land, even taking to the air.

And they’ve been evolving and radiating since way back in the Cambrian Period, over half-a-billion years ago, which can make studying  their origins pretty tough. But this tiny new fossil from China, Youti yuanshi, gave paleontologists a look at the perfectly preserved, fossilized organs inside one of the earliest ancestors of this group. It’s basically a 3D window into the past – many other fossils from this time period are squished flat, making it hard to see their internal anatomy.

Researchers x-ray CT scanned the fossil and could see its digestive glands, circulatory system, and nervous system. Their interpretation of the back half of the first segment of its brain suggests that, even this early-on, this structure might be linked to the development of specialized sensory organs in arthropods… And that Youti’s anatomy as a whole clarifies the order of the evolutionary steps needed to go from a simple worm-like ancestor to the euarthropods that have taken over the world today, complex brains, specialized feeding appendages, and all. Turns out, good things come in small packages.

Okay, I see your point about the teeny fossils being pretty cool too. how about this for a little wonder? This 90 million year old  rove beetle from Botswana, while tiny, represents a huge fossil find. That’s because despite beetles ruling the modern world … and I’m serious, there are so many kinds of beetles it’s mindblowing … we don’t really have as much as we’d like to go on when it comes to understanding their ancient history.

And by not much to go on, I mean this is only the fifth rove beetle fossil from this particular subfamily ever found! Not just fifth species, fifth beetle. And what’s special about this particular individual is that it, wasn’t particularly special at all!

Or rather, it’s pretty similar to the other rove beetle fossils from England, China, and Russia from around this time. Plus, this is the first one found in the Southern Hemisphere, showing us that they were already very widespread in the early Cretaceous, and may have even appeared in the Jurassic. So through this fossil we’ve learned that despite their very early global distribution, they haven’t changed much in the tens of millions of years since.

Modern day rove beetles make up the largest family of beetles, with tens of thousands of species found all over the world. Given that there are so many of them, you’d imagine that they’re extremely versatile, living in a wide range of environments under varying conditions. The rove beetles are still around today too, and can be found in lots of different locations, from inside your compost to nestled inside birds’ nests!

Despite all the variation in lifestyle, all rove beetles tend to look very… rove beetle-y. So the body form they’ve got seems to be working just fine across all kinds of scenarios, all over the world. Finding this one all the way in Botswana demonstrates that ancient rove beetles were way more widespread in the Cretaceous period than previously thought, and looked pretty similar for a very long time.

And that’s a big deal, because it lends support to an evolutionary model called punctuated evolution. The core principle is that evolution doesn’t always happen as a gradient, or a slow series of gradual changes. Instead, there can be long periods of relatively little change punctuated by huge morphological leaps and bounds.

So species like these that figured out a system and stuck with it really support that idea that sometimes, changes happen slowly, and then all at once. And then never again for a hundred million years or so. These are just a few of  the many incredible fossils found this year.

It just goes to show that we can learn so much from fossils both large, and of course, very, very small. I completely agree. But I’m still not gonna shut up about the giga-goose. [ OUTRO ]