 Okay, okay, I think I can start So thanks everyone for joining here This is some really fun work that I did in During my fellowship in Germany, some of you guys might have seen a previous presentation I did on the horse hunting Crocodiles, this is another really remarkable fossil from the same site So we'll be hearing about it a different project But set in the same kind of time and place there So I'll be communicating with you until all the moves slides. Here we go So before we dive into the the fossil record though a little very brief setup on what the modern Record is so what we've got here are What's called living archosaurs so archosaurs are birds and crocodiles they're fairly close relatives and then also included in this group are the Dinosaurs as we're used to thinking of them. So t-rex is an archosaur Excuse me stegosaurus is an archosaur all of the dinosaurs as well as the flying reptiles the pterosaurs So Now both of those actually exhibits parental care meaning that they do some sort of level of caring for their young Particularly when they're still in the egg so parsimony is something that basically just means the Kind of simplest solution is the most likely one more or less and that is sort of a guiding principle as we think about evolution so the assumption then would be that Parental care would actually be something that would be shared In not only crocodiles and birds, but everything that came between them namely the dinosaurs Now there's been a couple of very very rare cases where fossil dinosaurs are actually preserved With some of that behavioral trait with the eggs in direct association. So in the middle there, we've got a Kind of dinosaur known as the over raptors. This is a technically not over raptor, but don't worry about it But it's preserved with eggs and this thought to have actually been Brooding those eggs. This is like direct evidence of parental care Or at least exceedingly likely a case of parental care But the idea of these things having one shared sort of evolution of parental care Is kind of thrown a bit into question Because when we look at the fossil record for Terrasaurus that's again the flying reptiles. So things like quote-unquote pterodactyls and Pteranodons and Kitslquatlis all that stuff There's some evidence with their style of eggs that actually would suggest that they did not exhibit parental care and because Terrasaurus are actually Kind of between crocodiles and birds in terms of the evolution of archosaurs It actually starts to call into question exactly when parental care did come into place Because it's possible that it's actually something that evolved independently in those two lines So if it's evolved independently, then you don't know exactly when in crocodile evolution that came in Now there is still another explanation in that Terrasaurus might have lost that ability But because those become basically equivalent you don't really have a way of teasing it out so In order to do that you kind of need to start you know looking for some of these extraordinary cases of fossilization in the crocodile fossil record as well and However that that really requires some some very rare kind of preservation. So you need to not only get Good enough remains that you can identify the adult but you have to be able to recognize You know either eggs or young And a lot of the the eggs are fairly soft kinds of things. So are the So are the young inside so the babies tend to have even less of the Fossil records because their bones are so tiny and so fragile and not well formed Just a quick pause because it's not showing up on my screen Are you guys seeing A picture of like an alligator on a nest? Are you seeing a picture of a evolutionary tree? And I guess I should be on the other conversation Okay, let's go to the next slide. Sorry. It's it's being a little so, okay Okay, this is this is fine. So I think we got the fossil eggs up right now, right? Um, cool. That's fine. Um, so when we look at the A fossil record of crocodile eggs, there actually are quite a few they they range from kind of the middle of the age of the dinosaurs ish to Actually well after the mass extinction And lots of sites in between from around the world really they seem to have a similar Shape and style and and pattern that you would see in modern crocodile eggs Um, however, there weren't any of these cases of like direct Association with the parent like we see in the dinosaurs now. This is again exceedingly rare So just because you know, they hadn't been found for a really long time doesn't mean that You know, it wasn't there. This is just a very very unusual circumstance. It needs very very special Kind of geological situation in order to preserve Um Now there actually is a record A historical record the oldest one that i'm aware of by far is a petroglyph That was found in libya dating back to about 9 000 years old Where humans had actually carved into the side of the rock a mother crocodile with a baby Um showing that this uh, this you know characteristic has been observed by people for Quite a very very long time Which is pretty extraordinary in its own right, but we want to get into the fossil record. We want to get into the old old stuff So it requires this really really rare kind of preservation Now luckily there are a few places where fossilization Is just exceptional just beyond what we normally get in most places in the world um And a lot of this has been gathered up at the geisel tall collection in holla germany, um, which is uh part of martin luther university tatery university Which is where i was fortunate enough to work for two years on a fellowship Um, the preservation there is just just incredible. Um, so what you're seeing in the bottom right is a fossil beetle that actually has um Kind of preservation of some of the the cells that kind of cause iridescence um As well as really just everything across ecosystem from Plants to um all the little animals frogs uh salamanders fish um the big crocodiles these taper like things All of which were in a setting of um more or less a set of subtropical islands, so picture kind of a Something kind of like the Mediterranean today, but with really really lush vegetation. So just You know really diverse very wet warm environment absolutely great for all kinds of things to thrive And the spot we're specifically talking about is that red dot, um, which is not Looks to kind of close to the coast but the coast still would have been like, you know 1215 miles away something like that like Not that far away, but not close enough that you call it like a coastal environment still very much a jungle kind of environment um, and you just get everything and it's best incredible And that is where you can get something like this now This is actually a fossil that was collected in the 1930s. It's absolutely incredible and when I was uh, I got there You know being the the crocodile lever that I am I immediately started going through all the the crocodile material And when I saw this I was just absolutely floored I had never Never in my life seen anything like this or even heard of something like this even existing anywhere Um, I I've been to many museums all over the place have seen many many fossil crocodiles Some of which have been really really well preserved, but this absolutely floored me as Absolutely exceptional and extraordinary in every way. Um, so what we're looking at here And we'll go to the next one that's got a bit of a line drawing that it did um Is a sketch of that same thing here, but highlighted in yellow are fossilized eggs that were preserved in place immediately adjacent to An adult crocodilian now. This is Diplocyanodon. This is a It's closer to alligators really so it's in an extinct line That's actually kind of a bit a bit more close to alligators and caimans than it is to crocodiles We typically use the word crocodilian, especially when we spell it with an eye for technical reasons That this is actually something that was um We can Generally just kind of refer to these as uh, crocodiles, although if you want to get technical It's it's a lot closer an alligator, but I'll just for simplicity's sake. We'll we'll call it a croc for now um and When you look at the the eggs that were preserved with the mother they match up really well with other Uh fossil crocodilian eggs that were found at the same site So even though they weren't found in direct association with an adult like this one um the Shell and everything about the size texture everything actually matched up really well with Um, something that's referred to as an o-o species. We actually have different scientific names for fossilized eggs Um, but this matched up very very well with fossil crocodile eggs that have been recognized from that site Okay, um now in order to start kind of giving a little bit more confidence to these eggs belonging to Or you know this being a mother egg scenario There's actually really good data for existing relatives So it'd be the alligators and the caimans For the size of an egg that a mother would be expected to lay So we can actually look at that based on measurements of the eggs of the fossil now Those eggs are crushed a bit. Um, so it does Very slightly change The the overall length, but you're still getting very very close. So within that we got a little bit of a range Not very much of the fossil eggs. So if you take that You take measurements of the mother um, you can sort of predict what you would expect um for The size of the egg for the size of the mother and this is uh, usually In crocodilians and most reptiles really we talk in terms of what's called the snout vent length or svl um, this is basically an approximation of size To to give you what that really means from the tip of the snout to the cloaca Which is where all the business happens. It's basically the butt The reason why that's used is because tail length Because a lot of reptiles end up Losing bits of their tail is actually very common through usually inter species aggression and intra Where uh, for one reason or another they lose little bits of tail So we end up actually using this svl instead of total body length Instead which seems a bit odd. But anyway proxy for size, right? And the eggs really match up with the kind of size that you would expect based on the eggs You can also work that back the other way from the egg to the mother again, you get Or sorry from the mother to the eggs to the size of the mother What kind of eggs size eggs would you expect again? You get something that falls within the range of what we're seeing in the fossil there So in terms of size relationship between the two They're all pretty darn consistent. Um, so there's no surprises there Now this fossil came from a really widely exposed part of what was an open pit coal mine That was excavated out for a long long time. Um, obviously this happened in the 1930s But it continued up into the 1990s. Um, it actually after that was retired and actually flooded So you can no longer actually find any fossils at the site. It was a little too bad But they did pull out a lot of good stuff Um, and this is within one single stratigraphic horizon. So it's all effectively Um, at least geologically speaking occurred at one point Now this was meticulously documented and thankfully for that, um into, um, what was basically a small distributed, uh, publication Um, and in that included a site map, which was really really good for me Who obviously was not alive the 1930s to have seen any of this? Um, and they recorded everything everything I'm talking every little fish and not just like putting down where a fish was found within these meter grids But also putting the orientation of each of those. So if it was facing north south east west that kind of thing is Really really extraordinarily detailed and within that they did include this nice little sketch Of, um, the crocodile with the eggs there. So really really useful stuff Um, for any of those that might be familiar with german, you might have actually noticed Uh, the term lichenfeld at the top here. Um, it's it's difficult to, uh Properly translate it into english, but it it's basically Forbes field or dying field. It's it's field of of bodies more or less Which sounds pretty graphic. It kind of is I get the impression that in in german It's not quite as as graphic in english, but uh, there's really not a better translation really Um, because you've got a bunch of these things all together there Um, so it's still kind of it's neat. Um, and um, there's there's a possibility That these things effectively died In a very narrow window of time Um, in terms of what that environment would have looked like, um, it would have actually been something pretty similar to This picture here, which is where you actually typically would expect to find something like an alligator Making a nest which we actually got with the arrow pointing there Um, so lots and lots of water lots and lots of vegetation That vegetation is key because that's what's actually building up most of the deposit there again This is uh, what's called a brown coal or a lignite deposit Which is effectively just kind of decaying plant matter that built up over a very long over a period of time here um, so the fossils are actually coming Really within the lignite itself, which is actually pretty rare in terms of geology Normally these come in layers in between the coal layers. These are actually within the coal itself Now in terms of the kinds of, um, creatures that are found there, animals in particular, um, they are Almost exclusively aquatic So we're seeing these things that are spending a lot of time in the water So things like fish crayfish clams are making up, um, the majority of what we're finding there With just a few things that you would call sort of amphibious things that spend time on land and water And then even fewer things that have, um, That are dominantly terrestrial so things like the horses Um, so kind of sets the the environmental stage there a little bit um now in terms of What we actually in terms of other crocodiles, right? Um, since this is so well mapped out We can actually measure out how far the nearest crocodile was and it was 12 meters away So this is a significant distance. It's not You know, particularly nearby so the um idea that maybe kind of these crocodile eggs were here and coincidentally An adult floated by or something like that is extraordinarily unlikely Um, so that you know, there's not like, you know, crocodiles all over the place You don't necessarily even know which one goes to which this seems like very good evidence that this is a direct association between the eggs and the adults here And we're able to to tease that out because of such good records that they made now in terms of looking at how mature the adult is um, we actually see there's a tool that we use in fossil crocodiles Based on how modern crocodiles grow is that the vertebral column the spinal column which is made of a vertebrae There's one part called a centrum that fuses on to the neural arch which is Kind of together what uh brackets the spinal cord itself And those two pieces fuse as the individual gets older and that basically starts at the tail and goes to the neck So what we're seeing is fully fused tail vertebrae and back vertebrae But the neck vertebrae are actually not fully fused Now that you might think that that might actually indicate that it's immature and it does mean that it's not a particularly old individual But when we compare What we got here is a diagram of how those bones fuse from basically hatching to Kind of old old age Hatching on the left old old age on the right And what you'll notice is there's a point where sexual maturity has reached long before The bones of the neck actually fuse in fact a lot of even old individuals still don't have fused neck vertebrae So this is showing that you know, okay We're we're still within the the realm of where we would expect these things to have reached sexual maturity Obviously if it's laying eggs, it has to have reached sexual maturity by definition And what we're also noticing here in orange is where this the body sizes of this diplocynodon I should note diplocynodon does not Does not reach the the large body size of the alligators can so this is clearly reaching a sexual maturity at Definitely much smaller size than we would typically see it in alligator but given that the maximum size of these Diplocynodon the fossil one is about One meter meter and a half something like that then, you know, that's not too surprising really But it's great that we can actually like address issues of sexual maturity in this fossil, which is just just exceptional um So we've got this really really rare case of of preservation here. Sorry my my screen is just like not loading So all I'm seeing is a blurry version. I'm going off of memory here, but I'm pretty sure we can move on to the next one um Oh, right. So the the really important thing though to keep in mind as we start to try and figure out what happened here um, how this fossil came to be and what it can tell us Is how it actually was collected and this is the most important piece that you need to know Um, because you might see that really great fossil. It's got the the skull up Lying there in beautiful detail the eggs lying out next to it but The way these things were collected back in the 1930s. They were finding the coal workers were finding these great fossil skeletons there They're like, oh my gosh, we've got to preserve this stuff. This is really really really important But because it's so crumbly and fragmentary if you were to pick these things up It would just disintegrate into dust you would have nothing at all Um, and they really wanted to preserve these things In place as much as possible because you're getting like all the little finger bones next to each other You want to preserve that association because that has a lot of importance for how you then Take the next steps for the scientific research So what they came up with in the 1930s, um, was to Basically melt paraffin wax so they would actually manage to get a pot out there melts up this wax in the field in the pit And they would pour this melted wax directly onto the fossil bones Then that would of course, um harden as it dried out and cooled off Um, and you would basically have Whatever it was embedded in wax and that, um may seem like yeah Maybe not the best way to do it. Um, it actually it kind of worked. Um, and the fact that these things are actually Still still in the same wax that they were put in in the 1930s and that wax is still there It's still together hasn't like cracked into pieces Is actually testament to you know, their foresight and ability to come up with a workable solution in the 1930s um, so However, that means that they found this thing they built like a little wall around it pour the wax since the wax wouldn't Just go all over the place Then they would cover that with plaster And flip it over And bring that back to the lab and they would work down the rock there in the lab where they could do that nice and carefully without Um, kind of jostling anything or moving anything any further And then they basically leave it in the wax that it was in So that means when you actually see the final product as it would have been It actually means the other way was up when they found it So this of course has very very big significance for, um, how you then interpret that, right? Now they did prepare through the wax much later To get to the the bottom side of the skull here because they wanted to see some details that help You figure out exactly which species of Diplocyanodon it was Um, they didn't continue through because they wanted to kind of still keep everything together If you take away the wax and you don't really have anything that that bonds that together anymore, right? Um, so this is more or less kind of how this would have been When it was actually found in the field so it would have been in this sort of belly up position Now one other thing that's really really, um One thing that's come up is, um The fact that it's actually curved around its trunk is actually really really really weird So the fact that it's got its head curved around to the side of its body with its tail wrapped around it as well Is not normal at all. So when you look at some skeletons, you might have be familiar with especially from like the Jurassic Park movies Where the neck is actually curved back around onto the Backwards onto the back, um, which is epistotonic kind of this perimortem preservation style so that basically is, um Something that's actually exclusive to things that have long necks So we see that in certain kinds of dinosaurs. We see that in certain kinds of birds um, and a few other kinds of things that have these long necks where basically through some natural processes that neck can actually, um come back around now this actually often comes up in cases where these things are being preserved in water because Actually has to do with buoyancy of the body versus buoyancy of the head So because there's some differences there that actually causes the neck to sort of float for a bit and then slowly as kind of Kind of gases make their way out of the body very slowly and dissolve into the water That back and head will settle and can settle in this kind of what looks like a contorted position But this is really exclusive to this kind of sort of as we would say Kind of dorsal ventures basically meaning that it would go towards the back not towards the side of the body um So that really doesn't explain what we're seeing in this fossil crocodilian now There actually is evidence that was actually done by the same guy that was mapping out this Leichenfeld this coarse field in germany did a bunch of studies in actually texas same german dude And included in that some alligator carcasses that were basically put in a situation where It was kind of fenced off So you didn't have to worry about coyotes coming in and dragging things off But they'd be more or less left to just rot as nature would And if you give an alligator an opportunity to just sit there and decay Um it more or less stays in the same position you get a little bit of disarticulation happening But if you have this just sitting out on land you get more or less the same position it was in when it died Where the bones are really um and the skin kind of more or less Holds those in place to certain extent um So we don't expect any real curvature happening in any direction if you allow this thing to just dry out on land And maybe you have little bugs and stuff eat away at it Now if we're talking in water that is a bit of a different circumstance there In water, um after a few days you do get um what's called a bloat phase Where these things will actually invert so they'll go belly up Um and this was done. Uh, they did a couple of cases. Um where they're basically put um recently deceased crocodiles these were naturally deceased um And uh put them into effectively fish tanks and The different uh things to them to just kind of see what would happen there And it takes about four and a half days for that to um basically But it caused the inversion and then it would kind of slowly drift down to uh the bottom of the You know, whatever body of water that it's in Um so in three different scenarios, we're looking at uh outlines of skeletons from this study And all the way to the left is where um these things were put in there right side up and they were buried So just piled dirt on top of them. So this is a rapid burial scenario And in that scenario, actually there's no inversion happens. Everything stays under the dirt and basically stays exactly as it was in life So there's no change happening there whatsoever in the middle scenario, they um Allowed the belly up phase to happen and then buried it and in that case you do get a good bit of uh, you get some Disarticulation, right? So you got some of the limbs aren't quite where they were in life Everything is still pretty much in place and importantly that spinal column is still pretty darn straight If you do nothing if you just throw that crocodile in there, it goes belly up It just falls back down just don't even bury it at all just let it sit there You get the case all the way on the right there where things are definitely more jumbled up, right? So you don't not getting this nice beautiful laid out skeleton, but there's still some decent association there, right? You're still seeing a spinal column. That's still pretty darn straight there Um and uh, you're you know, you're still getting some kind of association there even if it's not Everything as as you would have expected as it was in life um Now there's one other component here that um should be kind of considered and that is Flow, so we know that there's a good bit of water around there Was there a current? That would be influencing kind of the the orientation of this crocodile Um now because they took such meticulous notes there you can actually start to you can actually address this question directly So what I did is I took the one meter grid there. They're about um a couple hundred Skeletons, they're mostly fish fish are actually great though because they're basically a compass needle, right? So using that in the other kind of skeletons that were there I was able to get compass directions based on the notes here of How these things were oriented and from that you can actually quantify those compass directions into what's called a Rose diagram, which is this thing on the right here Basically what this is is taking things in I'm pretty sure is five degree bins of that compass direction and had there been a consistent flow You would expect to see um Really really strong orientation. So you should see really in one direction But uh failing that in in two directions very very strongly with really nothing showing up in any other direction If there is a consistent flow um Basically, if you run the stats on this it doesn't add up to anything you would call statistically significant There is a weak correlation kind of going more or less north south there. Um, just a little bit off Um, but it's it's not even statistically valid. So it doesn't seem like there's a strong current That would have been influencing this so it's it's really not accounting for the orientation of the the crocodile either Next all right So what did happen? Um as you probably start to pick up here. I've spent a lot of time thinking about this The short answer is like you're never really gonna know there But from having gone into all this stuff here and and try to come up with The most likely scenario to me and I will admit there are absolutely other ways you can interpret this But from spending the huge amount of time that I have on this This is the scenario that I've come up with that kind of jives the best for me looking at what I've been able to learn from this One thing to keep in mind that I actually haven't brought up here is that egg clutches are usually much larger than the five eggs that were preserved with this Uh, Diplocyanodon normally they're you know 20 or even more eggs, right? So Your scenario sort of needs to also include why there aren't more eggs, right? So I should also point out there was one leg that was actually detached from the body. It was actually Just a little bit a ways over kind of by the other eggs there So the scenario I came up with um keeping in mind that Alligators and caimans make their nests in mounds of vegetation, right? So the mother Made this amount of vegetation you add all the eggs in there and they typically just kind of sit there curled around it Protecting it Until the eggs are ready to hatch and they'll kind of go off to catch some food, but then they come back They're you they're never very far away from the nest, right? So it's very normal for these things to be curled around their mound of eggs there, right? So in this scenario she dies more or less in place on the mount and Is basically allowed to desiccate there The egg nest is either rated by other animals. So a bunch of the eggs get taken Or they basically fall out from the nest and otherwise disassociated from the rest of them, right? During that desiccation we do see some of these limbs tend to kind of Come away from the body or aren't as clearly attached at some point Simply following following gravity the body flips Just falling off the mound itself as it maybe dries out and is no longer able to support it That allows for the inversion the leg that already detached during desiccation is left there You've got the egg still in their place and over time Plants come in start growing up all throughout that and start dying and building that mats water Probably gets involved at some point as well allowing for these kinds of things to Basically build up and get preserved in place and sorry. I'm trying to like catch It's it's hard to to watch the the chat here, but I did see somebody say could the eggs have hatched actually No, because typically you would see a very clear exit point for the eggs And we're not seeing that And we're also not seeing really any remains within everything is is pretty compressed within a single plane um and the the most likely explanation for that is that the Eggs also died pretty early into their developments that they didn't actually even get to the point where they're they're making solid bones yet Um, so that they they wouldn't really have much of a chance for fossilizing. I will again admit there are other explanations out there Um now in terms of what actually caused the death, um There are a bunch of reasons that could be out there. You can never really rule out disease Most diseases don't leave any signs whatsoever in the bone Um, but crocodilians tend to be pretty hearty um, and there was actually uh an interesting case that happened that that might give us some idea of not only why the the mother crocodile died, but Excuse me. Why um, why there's this corpse field or this field of death? Um Uh is here and that might have to do with temperature So when we look at uh things like the plants have actually in other past studies have given us Really good climate data um in the form of Among other things the coldest month mean temperature. So what that means is What was the average temperature of the coldest month of the year? represented at geisel tom we actually figured out out based on the plant fossil record um And from that we can actually look at similar environments today That have similar coldest month mean temperatures and one of them Is the florida everglades now the florida everglades is in very far south florida Where it's really really really nice and warm. You're pretty much year round even in the coldest month And um in that environment you get both alligators and crocodiles as well as a bunch of fish and stuff and a lot of those things are um kind of used to Uh warm temperatures right so things like the crocodiles really don't show up any further north than that They're not used to cold month mean temperatures any colder than the florida everglades there and In 2010 there is um a cold snap meaning that temperatures got weirdly low Like way lower than they normally do for the coldest month mean temperature And it caused the death of a lot of crocodiles It also caused the death of a lot of the more tropical fish and it was really the only more cold tolerant animals to actually survive through this cold snap there um Notably also this study was another study was done in south carolina where um Cayman were kept outside. It's not a great scenario, but it's something that happened And a bunch of cayman died because they were not adapted to weirdly cold temperatures um and It's it's at least possible that this is what led to the death of of mother of eggs of um even The other animals that were around at the time So it's it's just kind of more or less a possibility really looking at Kinds of scenarios out there of again fully admit that there are other ways that might explain this um now This is actually this is a painting in the geisel tall museum that was done Uh number of years ago us actually on directly onto the wall here of this Lichenfeld or this corpse field of this kind of death and destruction here This is a possible scenario again not the only explanation out there But a possible case for why these things were all gathered in death together here um, there's one Other explanation though for how this mother might have died It actually has nothing to do with temperature and that is something called dystocia Now this is not a well known thing. Um, but it's basically egg binding This is where um during the process of egg laying an egg more or less gets stuck in the canal of the mother and um, no other eggs can get out Um, and this is usually in the process of sometimes like she'll lay some but then something will get stuck Um, and it's really bad. It's really bad. Now. This is Much much more common in snakes lizards and turtles Um, and it's actually exceptionally rare in crocodiles. I could actually only find one One record of this happening in crocodiles. It doesn't mean that hasn't happened other times in the past Even in, you know, human history, but it's only been actually documented one time that I could find um And it leads to death of the mother every time unless it's you know, there's human intervention It typically takes a few weeks. It's not a quick death by any means and in that scenario if You know, we do have an egg that's preserved somewhere near the the quote-unquote Vent or where the egg would have been laid of the mother if that's the case That still actually means that she was staying with those eggs that she had laid and did not leave and died with them right there So even if that's the case of you know, she died from dystocia and not from cold That's still showing your parental behavior there that she stuck with them until her very end. Um, which is still You know, not only incredible in that sense, but if this is in fact dystocia This is actually so far as I know the um one and only case in the fossil record where that's been shown For any arkasaur for that includes um birds dinosaurs all that other stuff I could not find a case of dystocia Shown in the fossil record for any of these other animals So this would actually be the first case of that into the fossil record for any arkasaur Crazy again because there's other scenarios. It's not you know, it's not a slam dunk that that it was dystocia Although it's got some some some things going for it. Um, one last uh thing that kind of came up during the review process Was this idea of post mortem quote-unquote birth This comes up a lot for ichthyosaurs, which is what's shown here It's basically if you don't know what they are, they're like a reptilian dolphin. They're really weird animals. Anyway, um, a bunch of these have been preserved where A baby is basically Preserved in what seems like the act of birth, right? So, you know birth went Parashaped and both the mother and the baby died together there um Some people had argued that maybe gases building up in the body of the mother Would have actually pushed the baby out. So actually it was just a pregnant mother that died And not one that was in the act of giving birth and that the gases pushed the baby out. This is actually refuted pretty definitively Because the gases that are the results of putrefaction in a subaquatic environment Are are soluble. They basically just go directly into the water So you wouldn't really be getting that gas build up. You wouldn't be getting the pressure There are there's still the possibility of currents explaining why these things would become Why the the baby would kind of come out of it As well as gravitational collapse. So like, uh, you know, the the weight of you know, part of the body of the mother Might have been enough to push it out. That doesn't seem very likely Instead seems like it's more like the the original interpretation that this was basically a failed birth process that Ended very tragically for the both of them So, uh, some takeaways here. Um, this does extend My opinion pretty definitively Evidence of parental care back 45 million years into the fossil crocodilian record So that shows that there is at least that much antiquity to parental behavior in crocodilians It's still not refuting that this isn't something that goes way back to the beginning But it's actually adding to that and supporting that um We can also, um, potentially have the first case of dystocia or we might have some explanation for why everything died there And uh, it shows a definite case for sexual maturity So a really good indicator in a fossil species there, which is very very rare to be able to do that As well as a direct association for this. Oh species the species of fossil egg with the Um species of crocodilian that's laid it which is all super super remarkable and incredible um All right, so a few thank yous. Uh, I did have a co-author here. Meinolf helman dr. Meinolf helman Uh, who unfortunately did pass away a couple years ago, but he helped out a lot He was a curator at the gazel tol collection Um, and my uh fellowship was funded by the kulturstift undismundes Um, which is the federal cultural foundation of germany So that was all super I had one more slide of just some Fits some stuff. Maybe that was it. Maybe that was it. Hey guys, thank you very much to everybody here for staying with me and We've got some time here. So I will Take some questions. Yes. That is the end of it. There are no whistles. Okay, great So thank you very much very much. Um, and I oh boy this chat box is full So, uh, particularly if you got some burning questions, go ahead and put them in the chat now Even if you already asked them Uh, because I have not seen them and that's a lot to scroll through in a short amount of time Um, I should also add um as I as I'm pretty sure shantel put in the the chat box There is a fireside chat. Uh, that'll be doing on monday at 9 a.m. Pacific 11 a.m. My time um, so If you don't get a chance to talk about your stuff and you have a chance to come in We can certainly chat some more about this stuff then But we do have some a few minutes now. So if you got Um, some questions that you want to get in there go ahead and drop them into the chat box and I will take them And thank you again. Yeah, and shantel just put the fireside chat in again. Thank you Uh, okay. How old is the fossil? It is about 45 million years old. So that puts it in the Eocene, um, which is uh, not right after the age of the dinosaur is actually the one after that So it's you know, it's a decent time afterwards, but it's still Kind of a not anywhere near the kind of world that we have today It was actually much hotter back at the time, which is part of why you get such really cool Um, reptiles in a place like europe where you know, you can't support any Crocodilian species in germany today at all. It's just much too cold Is the shape of the fossil due to its decay process or an indication of how it died um Both really um, so it's uh I mean, there's a few kind of ways to look at it, but in terms of the curvature You really can't explain it just on decay alone. There has to be another thing there and what seems to be Paces is kind of how it was when it died In in my opinion based on on all that I learned from this Was a factor in in how it came to be preserved in the position that was in there's just really No natural decay process that would explain that curvature Uh, let's see. So the croc is a bit maternal here. That's that's what it seems to be really um How does this creature differ from modern animals smaller matures more quickly any other characteristics? So there's actually a lot of Diplocynodon that have been found at this site. So this exact species And they seem to really max out at about like three feet three feet and a little bit In length or about one meter Um, so they're not a big species. They're smaller certainly than modern alligators. Um, and they might have reached maturity at kind of younger or older ages, but um One thing we can say is that at least in terms of size. They're definitely doing it at smaller body size. So this adult Is you know was um just a little bit under sort of the maximum Body size that we're seeing for the species. So this is still Kind of hitting sexual maturity before kind of the the biggest that it could have been expected to get to um So the croc exhibit maternal care isn't that rare for a cold-blooded organism. It's actually not rare Actually all all modern crocodiles and alligators all the different species At the very very least Do nest attendants so they lay their eggs and they stay with them and do not leave and will defend that fiercely from Predators and anything else that might come into them. Um And that's pretty much across the board Um, you also I mean you not only see that in birds, which are of course warm-blooded, but you actually see that in um, certain species of snakes As well as certain species of lizards that will actually At the very least kind of watch over the eggs Famously though, uh turtles do not do this. They are actually terrible parents. They don't really do anything at all They lay a ton of eggs and then they just piece out. That's it um So in the case of like sea turtles, they just you know Dig a hole bury them and then that's it. Good luck to you. Um, but it's actually common in a lot of other kinds of reptiles Yeah, so some fish will actually do parental care as well. That's kind of hit or miss as well They're definitely fish that don't do any parental care whatsoever There's some that will even you know actively eat their own children So it's it's pretty broad spectrum in terms of fish Uh, let's see. Oh, baby crocodile sort of chirp when they hatch. Um, it is I think the most adorable sound that exists on earth is Especially baby alligators that do this little what's called pipping noise Um, when they're you know coming out of their eggs, um, or even kind of when they're still young They're just trying to get the attention of an adult. Um, this is just a call out. I mean like hey, hey, hey um, and um Mothers in particular will respond directly to that noise and come And we'll fend off. So like, you know, if a predator is coming around They'll scare that off in response to that noise And what's interesting is It doesn't even necessarily have to be their own kits other adults will sometimes respond to that noise and fend off predators Um, so it's there's a little bit of kind of communal parenting that can happen within crocodilians Uh See is there a correlation between number of offspring and parental care? um If you're looking across all kinds of things that have kids typically parental care They exhibit more parental care the fewer children that they have usually So in the case of like if you take like humans, we typically just have one kid at a time and we have You know, we take care of our kids for years and years and years Um, so there's a lot more investment in that one species and when you look at certain kinds of birds that have Um, just like one egg or just a couple eggs They tend to really stick with their kids and really invest a lot of time and energy in that next generation Whereas they have larger um clutches than they do progressive typically do progressively less Care for them Something like a chicken doesn't do nearly the level of care that something like an eagle tends to but there's exceptions to all of that um so crocodilians do have a lot of of Kids or they have a large clutch anyway And they tend to stick around for like a year or a couple years sort of thing They will go on to have other clutches in that Meantime and they'll have progressively less kind of concern for their kids as they get older um So there's there's sort of kind of a spectrum to that and of course there's some exceptions But generally generally if you have fewer kids you invest more time and energy in in their health and well-being This is part of why sea turtles have so many eggs because they don't do anything at all um Yeah crocs are aquatics Um Let's okay Uh, so jay miami says last time I worked in a coal mine. We use dynamite rather than paraffin Uh, that's a very very different kind of procedure there That coal is carboniferous right in like apalachia But could we be using losing valuable tetrapod fossils most of what we get were plants? Um, I actually I shudder to think of how many fossils are lost through the mining process um It I I guarantee Wonderful amazing beautiful fossils have been lost all the time throughout the you know centuries and centuries of mining Just because of the nature of the mining process, especially when you start getting into explosives I guarantee many many Wondrous things have been blasted to smithereens over time um, but I try and stay on the folk on the positive side of that because um Really these mines um very rarely have any actual like legal obligation to preserve anything whatsoever um So the fact that they often do in these cases and usually just out of you know good faith You know a mine worker sees something that looks extraordinary and will will usually go out of their way to Preserve that as best they can sometimes, you know, there's just there's no stopping it like I talked to a guy who who operated uh Hurry on the virginia, north carolina border where you could get these footprints And he he said one time he had this big chopper and he saw the thing coming down the line Going to the chopper where he's going to get smashed to smithereens He saw these great footprints and he tried to shut he shut the machine off immediately But there's a lag time between when you shut it off and when it actually stops and it was too late He did the best he could but it chopped the thing into tiny little pieces and was completely obliterated That's a case where like, you know, the guy was really trying even though he had no obligation to stop it um, and and still, you know, you can't Can't prevent all tragedies from happening. So I I guarantee it's happened many many times even In, you know, with the the best of intentions out there But it's really only because of the mines existing in the first place that we have a lot of these things So if we weren't doing the mining, we wouldn't know these things existed. So, you know, it's there's pluses and minuses all around Uh, let's see mammals and birds crocodiles are from different reptilian lineages. That is true Um, so mammals came from what we refer to as mammal like reptiles So really reptiles came first and then mammals are branch off of that And that Split actually happened even before the age of the dinosaurs. Um, so by the age of the dinosaurs We have our mammal line. We have our um, our reptile line, including the reptiles We still have alive today and birds and dinosaurs all that good stuff Um goes way way way back, um to uh before even 250 million years ago And how scary it was out there for that very first mammal Yeah, uh, the first mammals were not big at all and there are definitely much larger predators out there The reptiles uh got to be Much bigger much faster much sooner than the mammals did Oh the mammal like reptiles are fascinating So the coolest thing that I like to bring up is uh, dimetrodon, which is that big sailback reptile Is actually a mammal like reptile. So it's not a mammal. Um, but it's on the mammal line So that actually means that it is more closely related to us as as human mammals Than it is to dinosaurs. So even though it shows up in the dinosaur toy kit all the time And often incorrectly gets called a dinosaur. It's actually closer to us than it is to dinosaurs. Really cool. I think that's amazing Endotherms do have certain advantages over ectotherms. I'd say uh being able to colonize cold places is the biggest one Um, you do see, you know, some like reptiles will make it up into some colder areas But in terms of like hitting diversity and large body size and really kind of commanding the ecosystem Mammals do cold environments way better than quote-unquote cold-blooded animals But in really greenhouse environments, it's not as clear-cut in a lot of cases in the past Uh reptiles actually do better than mammals in warm environments Uh, let's see Dude Dysinodonts are another mammal like reptile. They are super cool. Uh, some of them had these like really Um pronounced tusks too, which is really cool. The um one of the ways to describe Dysinodonts that The Smithsonian did recently was to call them tubby tusked and tough, which I like because they are all three of those things Uh, let's see maps like the german 1930s grid could be so packed with data By digital representation one could have pop-ups for each item from putting a cursor over the fossil icon That's absolutely true We could kind of turn that into a sort of gis exploration there because we have the fossils we have the map data Um, so you could actually reconstruct that and it's again I will sing the praises of the meticulousness of that team back in the 1930s To record all that data because you know a lot of this stuff wouldn't be known unless they had done that so Um major kudos to the thoroughness of 1930s scientists Some reptiles like verandas have limited ability to control body temperature. Um, yeah, so, uh, verandas which are your monitor lizards um live in Pretty much exclusively hot places So they're in places where um the temperature swings Very rarely get outside of kind of their normal comfort zone though. Um, they do live in both Wet and dry places that can handle some some variability in terms of how Wet the environment is but temperature a little less so But I think that's one of the reasons why you don't tend to see verandas in in cooler climates Whereas you do see things like hurdles and certain kinds of snakes can get into these cooler climates all right um, so we are kind of at time here And I am gonna have to log off here in a little bit But I'll just remind you guys again one more time if you want to Come in for the fireside chat on monday at 9 a.m. Pacific I'll be logged in for an hour then and that is just for chatting about whatever So happy to talk about any of this stuff anything else you might want to talk about in general I'm happy to talk about whatever Um, and that will be here at science circle. Um, so just log in come back here I'll be here and um, if you want to continue the conversation then And I will say thank you all again for listening and attending here today. Hope you liked it And have a great rest of your weekend. Thanks