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Sauropod necks 2 ( was Re: Dino reputation 'is exaggerated')
>From a practical perspective, I find Dr. Manning's
scenario much more convincing than the "ninja warrior
w/ a toe-dagger" image. I find the crampon analogy
apt, and feel that these animals were well-equipped
for merely for "hanging on" but actually climbing; not
towards the tops of trees or mountains, but toward the
vulnerable areas of sauropods/large herbivores. Also,
improving traction of the hind legs allows more force
to transmitted to be from the jaws to prey.
--- Dino Guy Ralph <email@example.com>
> Do we know enough about the keratin exterior to
> assess the function of this
> "Dino Guy" Ralph W. Miller III
> Docent at the California Academy of Sciences
> proud member of the Society of Vertebrate
> ----- Original Message -----
> From: "Allan Edels" <firstname.lastname@example.org>
> To: <email@example.com>
> Sent: Wednesday, October 12, 2005 9:08 AM
> Subject: Dino reputation 'is exaggerated'
> > >From the BBC:
> > http://news.bbc.co.uk/1/hi/sci/tech/4332272.stm
> > Text follows:
> > Dino reputation 'is exaggerated'
> > The dimensions of the hydraulic limb reflected
> what is known from the
> > fossil record
> > The _Velociraptor_ dinosaur made famous by the
> Hollywood movie Jurassic
> > Park may not have been quite the super-efficient
> killer we all thought.
> > Like other dinos in its family, it had a
> distinctive sickle-shaped claw on
> > the second toe which many have assumed was
> employed to disembowel victims.
> > But tests on a mechanical arm suggest this
> fearsome-looking appendage was
> > probably used just to hang on to prey.
> > UK scientists report their experiments in the
> journal Biology Letters.
> > "This dispels the myth in place for some 40 years
> that this was a
> > disembowelling claw - this is not the case," says
> Dr Phil Manning, from
> > the Manchester Museum, University of Manchester.
> > "I'm saying that the primary function of this claw
> was to hold on to the
> > prey, effectively like a climber's crampon," the
> curator of palaeontology
> > told the BBC News website.
> > _Velociraptor_ belonged to the Dromaeosauridae, a
> family of small to
> > medium-sized, lightly built and fast-running
> dinosaurs from the Cretaceous
> > Period (146 million to 65 million years ago) who
> appear from the fossil
> > record to have been very effective predators.
> > There is even evidence some, such as
> _Deinonychus_, hunted in packs.
> > They all possessed a large, curved claw on their
> big toes that could
> > rotate through an arc in excess of 200 degrees.
> > By kicking and slashing, it has been widely
> thought these creatures could
> > quickly open up their unfortunate victims, either
> killing them outright or
> > making them bleed so profusely death followed very
> > Dr Manning and his team tested the reputation on a
> robotic arm fitted with
> > a life-like Dromaeosaur claw. The set-up was based
> on detailed fossil
> > measurements.
> > The mechanical limb mimicked the sort of kick that
> might have come from a
> > 2m-long, 40kg _Velociraptor_. The Kevlar and
> carbon-fibre-coated aluminium
> > claw was thrust into the flesh from pig and
> crocodile carcasses.
> > Instead of producing the expected slashing wounds,
> the robotic impacts
> > created only small, rounded punctures.
> > What is more, the way the skin tissue bunched
> under the impacts prevented
> > the claw from withdrawing easily.
> > The punctures had a depth of about 30-40mm.
> > "It seems highly unlikely that wounds of this
> depth would have posed a
> > danger to the vital organs of a large herbivorous
> dinosaur, though they
> > would obviously be fatal to small prey," the team
> writes in Biology
> > Letters.
> > Dr Manning does not want people to think less of
> _Velociraptor_ or
> > _Deinonychus_ because of the research.
> > Its killing efficiency may not have matched their
> Hollywood image but the
> > creatures would still have presented a terrifying
> > "It's effectively like a fatal embrace," he told
> the BBC News website.
> > "These claws were used to hook into the flanks of
> prey larger than them so
> > the jaws could do the despatching.
> > "Imagine the scene: it's the Lower Cretaceous, and
> Tenontosaurs (large,
> > plant-eating dinosaurs) are grazing on ferns or
> cycads, going about their
> > everyday business," he added.
> > "Unbeknown to them, you've got a pack of predators
> stalking them.
> > "First, [the Dromaeosaurs] try to separate the
> animal they wish to kill by
> > running into the pack.
> > "The lead attacker then jumps on to the flanks of
> the animal, followed by
> > maybe two or three others, hooking the huge claws
> in their feet into the
> > animal and holding on with the re-curved claws on
> their hands.
> > "And once they're hooked into their prey, the
> razor sharp teeth of their
> > jaws go to work causing as much blood loss as
> possible to weaken the
> > animal.
> > "Eventually, the other animals come over for the
> kill, probably ripping
> > open the throat and stomach with their teeth - not
> their claws."
> > The results of research were first shown on The
> Truth about Killer
> > Dinosaurs, a BBC television production.
> > Note that these numbers are for _Velociraptor_,
> not the larger
> > _Deinonychus_.
> > Allan Edels