00:00it was a quite a long scene of dreadnoughtus uh here they are um a fight scene there was a
00:06fight
00:07scene uh in this um territorial battle between males and i i think this was actually kind of
00:14based on our science because um what we found with the two dreadnoughtus individuals
00:20is that the the much larger one the 65 ton one was osteologically that means its bones was
00:27osteologically quite young you might even think of it as a as a teenager who was growing rapidly at
00:32the time of its death whereas the one that we found that was one third smaller uh osteologically was
00:40much much older and so where do you find this in animals today where you find older smaller
00:45individuals and younger bigger individuals that's in species where you have um sexual dimorphism where
00:51the two sexes are of different sizes and usually that happens where you have male dominated sexual
00:58sexual selection which means that uh two alpha males are going to compete with each other to
01:04control a territory or a group of females there's also female dominated sexual selection that's where
01:09you see the males showing off with all kinds of colors and doing fancy tricks and buying corvettes
01:14and things like that um and so with dreadnoughtus we have just a hint you know that we have sexual
01:23dimorphism and then kind of a hint based on a hint that maybe it was male dominated sexual selection
01:29and that's what you are seeing here and then um these air sacs we got to talk about these air
01:35sacs yeah let's talk about the air sacs what do you think about that well the air sacs are kind
01:38of hard
01:39to miss um i have to tell you that there is zero evidence that dreadnoughtus had air sacs uh these
01:46are pneumatic gular pouches like a grouse would have today is it impossible no it's not impossible
01:55but we don't have any evidence that they do have that now i was told by the consultant on the
02:01show
02:01that um they wanted to find a way to illustrate the fact that extinct animals must have had amazing
02:10soft tissue structures that will never be preserved in the fossil record which is certainly true if we
02:15only knew elephants from their skeletons i probably wouldn't really know what an elephant looked like
02:21so this is an example of a hypothetical feature that maybe we're missing completely in the fossil record
02:29that could have existed did they specifically have this probably not is it impossible that they had
02:36this no it's also not but we don't have any evidence of it what we do have though is we
02:41have their cervical
02:42vertebrae vertical vertebrae and um the cervical vertebrae are very pneumatic meaning that they have
02:49a system of air tubes and air bladders um that invade the bone over the lifetime of the animal so
02:57the the
02:57bone becomes more honeycombed with air over time making it very light but still retaining most of
03:03the strength because if you have a 40 foot long neck right a 40 foot long lever you don't want
03:08to put a
03:08lot of weight at the end of that lever so they have these very lightly built pneumatic necks which i
03:14guess
03:14gave them the idea okay there's there's air in the neck there's a lot of air in the neck why
03:19not something
03:20like a like male grouses in the breeding season that have these pneumatic gular pouches that pop out like that
03:27i'm thinking of a story of droid nanas i know it's always interesting to draw inspiration from
03:35modern creatures there he goes i guess we'll have to hold out for any more fossil or soft tissue
03:42preservation yeah you know there's certain things that we're just never going to know and we kind of
03:46have to live with that disappointment um but there are a lot of soft tissue features that extinct
03:52creatures have that we're just never going to find um we can make inferences about them sometimes we
03:58can do that from um molecular work with modern creatures we can look at the dna from from groups
04:04of related creatures and and kind of figure out where that trait must have started occasionally you get
04:12soft tissue structures preserved if you have very uh clay deposits that can preserve that kind of
04:20resolution but that's very rare and i don't see that scenario happening for big things like
04:24sauropods that happens for little things like birds um and then you know there's always the promise of
04:30molecular paleontology where you know we routinely cover now recover um blood vessels and blood cells and
04:37proteins from dinosaurs and other extinct creatures um a few dna bases have been recovered is it possible
04:44we'll have a genome of a dinosaur and a lion avian dinosaur in the future you know it's it's a
04:50pretty
04:51high mountain to climb but i can't say that it's impossible
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