This specimen - a new species of Allosaurus according to our palaeontologists - was excavated in 2014 in central Wyoming. It’s 155 million years old (Jurassic), 8.7 metre long and 70% complete.
We’ve made a three-part series (+ bonus episode) on this incredible specimen: who is he or she? Why do our paleontologists think it is a new allosaur species? How old was Arkhane when it died? How fast did it grow compared to other dinosaurs? And what about its late-night snack: the nanosaurus?
Jurassic top predator Arkhane is the special guest at the Museum of Natural Sciences in Brussels. Nanosaurus probably was its late-night snack. Fossils of this small herbivorous dinosaur are rare, especially skulls. Watch how we reconstructed a squashed Nanosaurus skull!
This <TINY> scene from Jurassic Park stayed with me for a long time. In 1993 I was 9 years old. I knew about most “mainstream” dinosaurs, but things like “Metriacanthosaurus” were at a different, completely esoteric level of palaeontology. Its name sounded like a Mephistophelean demon. Internet was non-existent, and books were hard to reach. So I spent weeks, months, dreaming what sort of arcane, Delphic beast “Metriacanthosaurus” could have been - and dreamt that perhaps in five, ten years, Spielberg would film a JP sequel in which it would actually APPEAR.
Time: 201.3 million years ago, in the Rhaetian age of the Late Triassic of the Mesozoic of the Phanerozoic
Analogy: Did you ever play on a team in High School? Even like an academic one? I was on my school’s Science Olympiad team (always won a medal in fossils, thank you very much. I also was in charge of organizing bio events, no big deal). Anyway do you remember when, like, the upperclassmen graduated, and suddenly you had a lot of responsibility and you were an important member of whatever club or team you were on? Like, they disappeared, and you got to take their place and be the big guys? Yeah that’s this, but for dinosaurs.
Causes: Where did we leave off? Oh right nearly everything died. My favorite! Well life eventually did recover after the Permian Extinction - obviously, as we’re all here today. Archosauromorphs were really taking over the scene, and there we many different kinds everywhere - dinosaurs were a relative minority compared to all the other different types of reptiles, and pterosaurs were extremelyrare as well. Nothosaurs, Pachypleurosaurs, Placodonts, and the first Plesiosaurs evolved; there were Thalattosaurs, and Ichthyosaurs were verysuccessful in the Triassic. There were many amphibians, Rhynchosaurs, Phytosaurs, Aetosaurs, Rauisuchians, the first Crocodylians, Prolacertiformes, the earliest turtles, and the cynodonts all evolved and diversified, with cynodonts getting closer to being mammals. In fact, looking at the assemblage of the Triassic, one could hardly guess that it would be dinosaurs that would become the dominant megafauna of the Mesozoic period - various Pseudosuchians (crocodile-line Archosaurs) seemed to be taking that role.
So what happened then? After all, this is pretty quick after the last death machine - only about fifty million years. Well, the causes of this extinction are actually… not very clear. Once again people have tried to pin it on an asteroid - which would make somesense, since it was the large non-dinosaurian archosaurs that were hit the hardest - but no such crater has been found, and all possible candidates have been ruled out. There was some climate change and sea level fluctuations, but they weren’t sudden enough to explain the extinctions in the ocean - this was a very sudden pulse of death, more so than what you would expect from just gradual environmental fluctuations.
Theremayhave been some massive volcanic eruptions again - yay! more lava! - which seems to be the best bet. The flood basalts of the Central Atlantic Magmatic Province would have released carbon dioxide, sulfur dioxide, and aerosols, causing - once again - pretty terrible global warming and cooling. There seems to be evidence for a major CO2 greenhouse crisis in ocean extinction deposits, and evidence that both the marine and terrestrial extinctions happened at once, which may indicate that a sudden influx of carbon dioxide and accompanying warming caused the extinction. However, there’s a chance that the eruption of the CAMP was too old to have caused the extinction.
If it was the volcanic activity, perhaps exacerbated by already occurring climate change, then the increase in global temperatures would have had another terrible effect on life on the planet - which had just recovered, and thus would be fairly vulnerable.
Extinction Rate: This was not as bad of an extinction pulse as the last one, so if it was volcanic activity, it was the kind notin the worst possible place ever. Hooray! 23% of all families, 48% of all genera, and 70 to 75% of all species went extinct.
Effects: This was actually more acutely felt in the terrestrial environments than in the marine ones, though they were also affected. A large portion of the non-dinosaurian Archosauromorph groups went extinct, which emptied ecological niches on the land extensively. In the ocean, there seemed to just be less diversification - a decrease in speciation events rather than an extinction of already existing taxa. Phytosaurs and Aetosaurs were completely wiped out, as well as others.
If we can call any time periods much of anything, then, the Triassic was truly the age of reptiles, with a wide variety of forms and diversity across different major clades. One could argue, then that this age ended after the Triassic extinction - though many reptiles remained very common, it was really more specifically the Age of Dinosaurs after this point. Dinosaurs evolved to fill the vacant niches and finally started growing to the sizes to which we are accustomed with them - sauropods started evolving (at last, from stinking prosauropods), large theropods began to grow more and more common, and Ornithischians also finally had a chance to diverge.
In fact, the rapid pulse of diversification of dinosaurs after the end-Triassic extinction lead to a large morphological diversity of dinosaurs, and at some point between the middle and late Jurassic epochs, the earliest members of Avialae evolved - the group that would eventually lead to birds.
Mammals also evolved in the Early Jurassic, probably due to pressures following this extinction event. They remained small predators, living in regions where there was still many places to hide, though they did diversify somewhat, and more so than previous paleontologists believed.
So, though a relatively minor extinction, it once again directly lead to the world we know and love today - mammals became a thing, dinosaurs grew into what we really know and love about them (widely diverse and weird, because birds are weird you guys,) and other reptiles began to dominate the sea and air (hellooooo pterosaurs, pterosaurs everywhere). In fact, dinosaurs were so versatile and widely morphologically diverse following the Triassic extinction, thanks to all those sweet, sweet available niches, that they were very well adapted to their world.
Little paddle belonging to a juvenile Ichthyosaur. The small skeleton was found near Lyme Regis, a historic town on Britain’s Jurassic Coast where pioneer of palaeontology, Mary Anning, once lived. This skeleton is near complete and more photos will be coming soon once it’s fully prepared. . Follow @neojurassica to see more #prehistoric wonders! . www.neojurasssica.com Dinosaur Specialists Genuine Fossils ⚙️ Display Customisation Free UK Delivery ✈️ International Delivery . #ichthyosaur #ichthyosaurus #marinereptile #dinosaur #dinosaurs #dinosaurbones #dinosaurskeleton #skeleton #extinct #evolution #fossils #fossil #fossilhunting #fossilfriday #prehistory #naturalhistory #nature #history #archeology #palaeontology #paleontology #paleobiology #science #stem #jurassic #jurassicpark #jurassicworld #jurassiccoast #neojurassica https://www.instagram.com/p/CPImKTCNSvw/?utm_medium=tumblr
Two Femurs One is from our plesiosaur from Lyme Regis, one is from our Pliosaur (@mike_the_pliosaur). Can you guess which is which? . Follow @neojurassica to see more #prehistoric wonders! . www.neojurassica.com Dinosaur Specialists Genuine Fossils ⚙️ Display Customisation Free UK Delivery ✈️ International Delivery . #MikeThePliosaur #pliosaur #plesiosaur #plesiosaurus #plesiosaurs #fossils #fossil #fossilhunting #fossilfriday #paleontology #palaeontology #geology #science #bones #dinosaurbones #dinosaurs #dino #extinct #evolution #nature #naturalhistory #jurassic #jurassicpark #jurassicworld #neojurassica #walkingwithdinosaurs #archaeology #tropical #prehistoricanimals https://www.instagram.com/p/CPGQdZLN7jc/?utm_medium=tumblr
Most fossils aren’t perfect, but each tells a story. This #ammonite has its own story; from being born, to growing its shell, to surviving in the Jurassic seas, to eventual death. The preservation of the shell shows it wasn’t eaten, so this Ammonite may have lived a relatively peaceful life in the ocean. . Follow @neojurassica to see more #prehistoric wonders! . www.neojurassica.con Dinosaur Specialists Genuine Fossils ⚙️ Display Customisation Free UK Delivery ✈️ International Felivery . #ammonites #fossils #fossil #extinct #shell #seashell #nature #natural #naturalhistory #history #archaeology #palaeontology #paleontology #geology #science #discovery #adventure #rare #mysterious #artifact #jurassic #jurassicworld #neojurassica #paleoart #naturalart #prehistoricanimals #fossilhunting #whimsical https://www.instagram.com/p/CPEOtnBpGrN/?utm_medium=tumblr
Here we have two branchiosaurs that are over a quarter of a billion years old alongside some dinosaur bones from the Cretaceous era. This photo was taken a while back by an associate of ours for photography practice. . Follow @neojurassica to see more #prehistoric wonders! . www.neojurassica.com Dinosaur Specialists Genuine Fossils ⚙️ Display Customisation Free UK Delivery ✈️ International Delivery . #branchiosaurus #dinosaur #dinosaurs #dinosaurbones #extinct #extinction #art #paleoart #naturephotography #fossilphotography #nature #naturalhistory #history #archaeology #geology #paleontology #palaeontology #science #museum #naturalhistorymuseum #dinosaurmuseum #jurassic #jurassicpark #jurassicworld #neojurassica #past #future #fossils #prehistoricanimals https://www.instagram.com/p/CO-LWGMt7JG/?igshid=6dsu00fosq16
One of the rarest and strangest plants in the world, Welwitschia mirabilis is often referred to as an “underground tree” and can live up to 2,000 years in the arid Namib desert. It’s comprised of two leaves, a stem base and a tap root. The leaves become frayed but never stop growing and never shed, giving the plant it’s Medusa-like appearance. It uses them to collect moisture from sea fog. The long tap root can extend 6ft underground to collect water.
The only member of the Welwitschia genus, it’s thought to be a relic from the Jurassic Period, when the Earth was covered with ferns and gymnosperms, and thus a “living fossil”.
