Episode 500: Raptor Renaissance! – I Know Dino: The Large Dinosaur Podcast


Episode 500: Raptor Renaissance!. This historical past of dromaeosaurs (higher referred to as raptors). Plus an A to Z information of the most typical dinosaur phrases and inside of jokes from our first 500 episodes.

A few of our highest raptor resources (and a few info):

  • Dromaeosaurs have many fowl like options of their shoulders, wrists, and feathers supply
  • Each with fashionable raptors (birds of prey) and dromaeosaurs the foot is the fatal weapon supply
  • Utahraptor used to be came upon across the time the film Jurassic Park got here out, extra lately a brand new massive block of Utahraptors used to be discovered supply
  • Paleontologist Bob Bakker tells a compelling tale of a Utahraptor thru her eyes in his novel Raptor Purple supply
  • Paleontologist John Ostrom named Deinonychus in 1969 (which additionally has ties to Jurassic Park) supply
  • “The primary definitive dromaeosaur with a somewhat whole skeleton ever present in the USA” is nicknamed “Julietraptor” supply
  • A listing of all of the dromaeosaurids AKA “raptors” (as of 2012) supply

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The dinosaur of the day: Deinonychus

  • Dromaeosaurid theropod that lived within the Early Cretaceous in what’s now the U.S. (Montana, Utah, Wyoming, Oklahoma)
  • Discovered within the Cloverly Formation and Antlers Formation
  • Enamel that can belong to Deinonychus have additionally been present in Maryland (Potomac Formation)
  • Seemed very similar to Velociraptor, however a little larger
  • Estimated to develop as much as 3.4 m (11 feet) lengthy
  • Estimated to weigh as much as 100 kg (220 lb) in keeping with the femur and humerus (thigh bone and higher arm bone)
  • Walked on two legs
  • Had a triangular, huge cranium and slim snout
  • Had huge arms with 3 claws
  • More than likely coated in feathers, in keeping with it taking a look like a fowl and being carefully associated with different raptors (the place feathers had been discovered, similar to Microraptor and Velociraptor—quill knobs discovered at the arm of Velociraptor)
  • No direct proof of getting feathers, but
  • Had huge sickle-clawed 2nd toe (for reducing or slashing, no longer designed for greedy or digging)
  • 2nd toe used to be “tailored solely for predation”
  • Different ft round it helped with status and shifting
  • Sort and most effective species is Deinonychus antirrhopus
  • Genus title approach “horrible claw”
  • Genus title refers back to the huge, sickle-shaped claws on its 2nd ft
  • Species title antirrhopus approach “counter steadiness” and refers back to the stiff tail that can have helped it
  • On the other hand, one specimen of Velociraptor discovered later had a tail that curved and will have been in a position to bend to the edges
  • Fossils first present in 1931 close to Billings, Montana
  • Barnum Brown used to be main a group
  • Most commonly considering Tenontosaurus on the time however discussed the Deinonychus fossils have been “encased in lime tough to organize”
  • Informally named it “Daptosaurus agilis” and began to paintings on it, however didn’t end it
  • In the summertime of 1964, John Ostrom led an expedition with Yale’s Peabody Museum of Herbal Historical past close to Bridger, Montana (Cloverly Formation)
  • Over two summers discovered greater than 1,000 bones, from no less than 3 folks
  • Laborious to understand which bones belonged to which person, so laborious to understand precisely how many people
  • Sort specimen (holotype) of Deinonychus used to be only a left foot and partial proper foot (too laborious to understand which bones belonged to that individual person)
  • Sort specimen had a strongly curved sickle claw
  • Different specimens weren’t as strongly curved
  • Might be from person variation
  • Additionally discovered vertebrae, just about whole arms, portions of the cranium, foot bones, portions of the shoulder, portions of the tail, and extra
  • Later, Ostrom and Grant Meyer analyzed the fossils, in addition to the “Daptosaurus” and located all of them belonging to the similar species
  • “Daptosaurus” used to be most effective partially ready, however no longer studied
  • Ostrom mentioned “it’s only by accident” they’re incorporated within the find out about
  • Partially as a result of Dr. Edwin H. Colbert
  • Named all of them Deinonychus antirrhopus in 1969
  • In 1969, Ostrom, when he named Deinonychus, wrote: “A number of the vital discoveries made used to be that of the impressive little carnivorous dinosaur described right here—an animal so peculiar in its variations that it surely shall be a subject matter of serious pastime and debate for a few years amongst scholars of natural evolution”
  • “On the very second of discovery, it used to be glaring from the few fragments uncovered at the floor that we had stumbled throughout one thing very peculiar and fairly not like any up to now reported dinosaur”
  • Ostrom revealed a pair monographs on Deinonychus
  • Extra fossils present in 1974 to lend a hand fill in one of the most gaps (together with within the hip and pubis house)
  • Had extra of a fowl hip (backwards dealing with)
  • Ostrom’s description of Deinonychus result in the Dinosaur Renaissance (Nineteen Sixties to Eighties-ish the place scientists began seeing dinosaurs as extra lively and agile once more, as a substitute of sluggish, lumbering reptiles)
  • In 1969, Ostrom wrote that Deinonychus used to be evidence that dinosaurs have been lively (all in keeping with the foot)
  • “Individually, the foot of Deinonychus is most likely essentially the most revealing little bit of anatomical proof bearing on dinosaurian behavior and features to be came upon in lots of many years. Grandiose statements of this type are, in fact, simply rejected, however the useful implications of the pes of Deinonychus don’t seem to be so simply discarded—particularly in view of the opposite outstanding variations of this animal. Deinonychus will have to had been anything else however “reptilian” in its conduct, responses and way of living. It will have to had been a fleet-footed, extremely predaceous, extraordinarily agile and really lively animal, delicate to many stimuli and fast in its responses. Those in flip point out an peculiar degree of job for a reptile and recommend an surprisingly prime metabolic price. The proof for those lie mainly, however no longer solely, within the pes.”
  • Ostrom additionally wrote:
  • “It will have to be fairly evident that this instrument may no longer be used until the animal stood on one leg. Additionally it is evident that the usage of this construction necessitated important agility and maybe even violent job whilst status on that one limb.”
  • Deinonychus used to be an lively meat eater
  • Ostrom in 1969 mentioned it used to be a “flesh-eater and virtually no doubt a predator”
  • Sharp tooth, lengthy palms with claws at the arms, stiff tails, and sickle-like claws on the second one ft all would have helped
  • A find out about previous this yr, in 2024 by way of Tse, Miller, and Pittman discovered Deinonychus had a narrower cranium, had rather prime chew pressure/rather robust chew in comparison to different raptors
  • Had a tall, brief cranium
  • Sluggish, robust bites
  • However, prime pressure at the cranium
  • May just pass after huge prey, however cranium is rather much less proof against chew forces than different dromaeosaurids
  • Might be it used its neck muscle groups to drag again on prey, or perhaps had a large gape (may open its mouth huge)
  • Perhaps used its palms for greedy at prey or clutching gadgets towards its chest
  • Ostrom in 1969 laid out the concept that Deinonychus stuck and held prey in arms after which disemboweled it with its foot claws (which will require it stands on one foot whilst ripping the flesh with the claw of the other foot)
  • Ostriches and cassowaries could cause critical harm with the massive claws on their inside ft
  • One paper in 1958 by way of Gilliard “famous that the cassowary can simply sever an arm or disembowel a person with its lengthy sharp claws at the inside ft”
  • Some other paper in 1962 by way of Austin mentioned the “ostrich prefers to run, but if compelled to combat slashes out with robust kicks in a position to ripping open guy or lion”
  • Saved its sickle claw off the bottom, and walked on its 3rd and fourth ft as a substitute
  • Claws would had been even higher in lifestyles (coated in keratin)
  • Initially idea to chop and slash with claws
  • Later idea to stab at its prey
  • More moderen research discovered the claws have been just right for mountaineering (so may climb directly to prey, then pin it down and chew into it)
  • Will have killed prey by way of leaping directly to, gripping tightly with its claws, and begin to consume the animal whilst it’s nonetheless alive (after which sooner or later it dies from dropping blood and organ failure)
  • Referred to as the Raptor Prey Restraint (RPR) speculation
  • In response to evaluating the ft and legs of dromaeosaurs to trendy birds of prey (very similar to eagles and hawks, in keeping with Denver Fowler and others)
  • On the other hand, foot power from its shorter ft (had brief metatarsus or higher foot bones) can be extra very similar to owls
  • Hands will have been coated in lengthy feathers, that it would flap to lend a hand steadiness on best of the prey, along side the stiff tail
  • Research of the fowl seriemas (predatory, territorial birds, with lengthy legs and reddish beaks which can be small, weighing as much as virtually 5 lb or just a little over 2 kg)
  • Have recurved sickle claws that additionally they hang off the bottom like repeaters
  • Use them by way of pinning down prey after which they tear into the animal with their beaks
  • Very similar to the Raptor Prey Restraint (RPR) speculation that Fowler and others got here up with
  • In 2019 Peter Bishop made a 3-D fashion of Deinonychus legs and simulated the way it most probably labored. Discovered the claws have been in all probability for restraining prey and stabbing prey at shut vary (appear to peer this with Velociraptor within the Combating Dinosaurs, the place the Velociraptor is gripping Protoceratops with its claws). However may well be the sickle claw use varies a few of the raptors
  • A find out about in 2024, previous this yr, blended 3-D pictures and pc animation to visualise the actions of Deinonychus
  • Used 3-D fashions of fossils and data from x-ray movies of shifting joints of contemporary animals
  • Studied how they chased prey, swam, climbed, and extra
  • When compared x-ray movies of a contemporary fowl strolling on a treadmill, used the ones movies to measure ankle and toe joint poses of the fowl (guineafowl and emu)
  • Used 3-D fashions to simulate motions of the similar joints in pc animation instrument, checking out tens of millions of doable poses and ranking them on how neatly the fowl’s bone surfaces have compatibility in combination
  • When compared the perfect scoring doable poses with fact of the way the birds stroll, discovered a correct fit (just right for realizing if it’ll be correct in depicting prehistoric animal actions)
  • Used this method at the stride and foot strike of Deinonychus
  • Reconstructed the way it walked, the way it held its sickle claw off the bottom, the way it kicked to assault prey
  • Established a framework for the way joints are configured/articulated
  • Discovered Deinonychus tentatively did extra inflexible digit stabbing or pinning with claw, quite than slash or dig (stabbing additionally supported by way of Velociraptor discovered within the Combating Dinosaurs)
  • Showed it saved 2nd toe claw off the bottom (hyperextended posture right through locomotion)
  • Deinonychus has been discovered with regards to fossils of the ornithopod Tenontosaurus (DoD in ep 376)
  • (in over 50 Tenontosaurus websites, 14 even have Deinonychus fossils)
  • One Tenontosaurus discovered with bite marks from Deinonychus
  • A variety of artwork and statues display deficient Tenontosaurus being attacked
  • Tenontosaurus is larger than Deinonychus, and discovering them in combination might imply they hunted in packs
  • Or may well be they have been scavenging
  • Conceivable Deinonychus went after Tenontosaurus the best way that crocodiles or Komodo dragons these days feed (they generally tend to seek on my own or they begin to consume a carcass, after which different crocodiles or Komodo dragons display as much as consume the carcass they usually finally end up attacking every different. The biggest ones consume first. If the smaller ones get killed within the assault, they get eaten too)
  • Some Deinonychus folks discovered within the house with Tenontosaurus have been subadults and lacking portions of the frame that can imply they have been eaten by way of different Deinonychus
  • On the other hand, some crocodilians had been noticed searching in combination
  • And monitor websites of theropods appear to turn proof of searching in packs
  • Perhaps a little of each?
  • Juvenile Deinonychus used to be other from grownup Deinonychus
  • A 2015 find out about checked out expansion phases of Deinonychus (juvenile, subadult, and grownup)
  • In comparison to Bambiraptor
  • One specimen used to be between one and two years previous (bone histology, one LAG)
  • That one to 2 yr previous weighed between about 7 to nearly 9 kg (about 15 to twenty lb)
  • One specimen about 13 to fourteen years previous (grownup)
  • Juvenile Deinonychus had shorter, shallower jaws than adults
  • Had higher cranium and limb bones in comparison to the vertebral column than adults
  • As a juvenile, will have been in a position to flap
  • In response to the scale of the wrist joint, the lengthy palms and hand bones, the massive shoulder bones, turns out as a juvenile will have been in a position to perform a little flight like issues (like flap)
  • Would give the juvenile raptor a bonus (run sooner)
  • Would additionally give an explanation for the subadult of Bambiraptor having actually lengthy arm and hand bones
  • Additionally, the juvenile dromaeosaurid is estimated to be gentle sufficient that it would have flown (weight restrict for contemporary flying birds is ready 18 kg (virtually 40 lb)
  • However, Deinonychus would have modified because it grew up, so older Deinonychus wouldn’t be capable of fly/flap
  • Later research recognized a Deinonychus egg, the primary dromaeosaurid egg to be described
  • Eggshell used to be discovered with regards to Deinonychus gastralia (stomach ribs), which might imply Deinonychus brooded, to stay the eggs heat (very similar to fashionable birds, which might additionally imply Deinonychus used to be endothermic, or warm-blooded)
  • The Deinonychus that used to be most probably brooding used to be about 13 or 14 years previous and used to be achieved rising
  • A 2018 find out about discovered Deinonychus laid blue eggs (most certainly for camouflage)
  • Conceivable different raptors had colourful eggs
  • Lived in a swamp-like house or floodplain, perhaps very similar to what it’s like in Louisiana these days
  • Different dinosaurs that lived round the similar time and position come with nodosaurids like Sauropelta, ornithopods like Tenontosaurus and Zephyrosaurus, sauropods like Sauroposeidon
  • Different animals that lived round the similar time and position come with crocodilians and fish
  • Featured in Harry Adam Knight’s novel Carnosaur (horror novel revealed in 1984) as neatly the movie adaptation Carnosaur (got here out in 1993, a couple of month ahead of Jurassic Park)
  • Additionally in Michael Crichton’s novels Jurassic Park and The Misplaced Global and the Jurassic Park films (technically they’re Velociraptors, however they’re in keeping with Deinonychus, regardless that they’re the scale of Utahraptor)

A laugh Truth:

There may be fossil proof of theropod dinosaurs dancing.

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