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Ornithopods and Nodosaurids · Acedra
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Ornithopods and Nodosaurids
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2:05
These 2 nodosaurids are well equiped and fear only very few predators of the region.
2:16
Wandering, and benefiting from the still abundant water and nutrients, their life is still relatively confortable.
2:27
But this abundance is in reality fleeting.
2:32
Soon, the cyclical changes of the climate will make their life much harder
3:15
These small Ornithopods are called Orodromeus, meaning mountain runners. They’re about meter and a half in length, and live in groups.
3:26
This group is composed of a dozen of adults, comprising of both males and females.
3:36
This gregarious lifestyle increases their chances of spotting potential predators. 24 eyes is better than 2.
3:46
Currently they abide by the shores of this lake, but soon they will be forced to migrate to a crucial location, their nesting ground. The cause for such a radical move is that this place will severely suffer from the annual dry season, while the lands of their destination are more resistant to the droughts, thanks to the more resilient nature of the local vegetation. For now, they are benefiting from the shrubs and vegetation.
4:11
This place holds a rich flora composed of a variety of different plant types At this time of the year, it is semi arid, but it drastically changes throughout the seasons. Soon, most of the vegetation will disappear on the surface, but the roots will survive underground.
4:32
Due to the high mountains running along the western side of the continent, most of the rain clouds are blocked, but not all of them. This phenomenon is called rain shadowing.
5:51
Since their last appearance, the Herd of Orodromeus have found the nesting ground, and the group now counts new miniature members.
6:03
The common vegetation that the place offers of this time of the year happens to be scarcer. Fewer rains in the region are the likely cause. For that reason, the herd needs to move, hoping to find a more resourceful area.
6:40
Less rains in a dry environment also means less water,
6:52
but some animals are more resistant than others.
6:58
This Edmontonia for instance is several dozen times larger the any Orodromeus, allowing it to retain a greater volume of water within its body for longer The Edmontonia is not alone, as Carnivores also roam these parts. However, fighting this tank would likely result in a very probable death.
7:38
After several days of walking the Orodromeus have been spotted near a small pocket of water, The problem though is that they are not the only ones seeking to quench their thirst.
7:53
Giant hadrosaurs are the first on the scene. This species is called Hypacrosaurus
8:00
Their majestic body can reach up to 9 meters long Their main characteristic is the large rounded crest on the top of their head Formed from solid bone, it acts as a display structure. Much like other Hadrosaurs, they too live in herds.
8:26
The Orodromeus will have to wait.
8:32
Even so, the scarcity of water is likely to spark fierce competition between the larger herbivores, especially in such a time as this. The consequences of such would be life threatening to the herd of Orodromeus Any one of the animals at the watering hole could prove fatal if they near too close.
9:37
The cretaceous seas are filled with giant marine reptiles, situated at the very top of the food chain. But far away, on the coastline of Laramidia, lives a giant of another kind, a 12 meter long colossus, a crocodilian. However during these challenging times, few large herbivores are present near the coasts But like most crocodilians, its aptitude to adapt is remarkable For now, it will scour the seaway for whatever is unlucky enough to cross its path.
10:34
These are Stenonychosaurus, Troodontid Therapods.
10:41
They are characterised by their large eyes. But the key to their night vision is inside
10:49
Their retina counts a very high number of rods, the visual receptors responsible for night vision.
11:02
Those are the same that we have on our own eyes, but their concentration is no match.
11:09
However, more rods means fewers cones, giving the Stenonychosaurus a near monochromatic and not very detailed vision. But that is not an issue, they are nocturnal animals. Troodontids skull has an asymmetrical ear hole placement, much like modern owls, allowing them to accurately pin point small prey. The slightly forward facing nature of their eyes also allows them to perceive depth at a small degree.
11:42
The individuals we’ve found are living in a pair, and have comes across the corpse of an Orodromeus of which has succumbed to exhaustion.
12:37
Hunger is a serious concern for the predators during these rough times, and for Gorgosaurus this is no exception.
12:50
In fact, weeks have passed since its last meal, and it may not be long before it falls foul to starvation. Finding food now means the difference between life and death
13:02
Luckily, it has stumbled across the Hypacrosaurus herd
13:06
However, it isn’t at all in shape for hoping to catch one of them Yet it isn’t alone A female gorgosaurus is also patrolling the area in search of food. Such a proximity of these giants might usually result in a conflict of dramatic proportion, but a fighting isn’t a priority for the time being
13:55
surprisingly, during this harsh time, they will tolerate one other and ally to increase their chances of catching prey
14:20
They use their heightened numbers to more easily cause distress, drawing them into less flat terrain, where ambush is possible.
14:29
There is no real plan in action, neither a conscious strategy. These two carnivores are rather solely uniting their influence, allowing them to increase their chances of making a successful kill.
14:45
And it works.
14:54
The disorder created causes the animals to panic, as fear spreads like wildfire.
15:03
Their defensive structure broken, the predators now only need to single out their prey.
15:53
For the herd of Orodromeus, stress is at its maximum.
15:59
While we might never know the nature of their bond, it is certain that the group must continue its voyage, and will now be more cautious than ever.
16:59
The arid landscape has given way to one of lush and green
17:07
The seasonal rains have drastically transformed the region, creating an explosive rejuvination for the area's plant life. A welcome relief to our herd of Orodromeus, who are now able to hide more easily in the dense foliage.
17:31
The litter has also grown, with half of them having survived the perilous drought.
17:38
This turnover of the environnement pushes all the dinosaurs to adapt again.
17:44
As the predators never go to far from their potential prey, all the animals that we followed until now have moved to this place.
17:55
And so the ecosystem stays relatively stable all year round
18:02
However, there is an animal that comes to the mainland only seasonally.
18:10
The dinosaur eater is taking advantage of the presence of large herbivores, and has, like each year, entered the mainland riversystem, hoping to catch something. But this won’t be an easy task.
18:42
The inhabitants of Laramidia face annual challenges, wether climatic, competitive, or predatory.
18:49
Their ability to rapidly adapt is the reason of their very persistence.
18:56
But even these harsh changes are subject to change. Changes that will cause the end of species like the Orodromeus, and the rise of new ones, filling their niche in millenia to come.
19:11
The end of the cretaceous marks the emergence of Angiosperms, plants carrying flowers, leading to a profound change in the ecosystems, and the appearance of new unique symbiotic relations.
19:25
The western interior seaway will gradually disappear, with the formation and growth of permanent ice caps, and the reduction of the sea levels. Original subtitles made by Past Eons Don't forget to subscribe to stay tuned :) Thank you for watching <3
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