Oh well, carry on with the flying brickbats...
Posted on 07/03/2006 12:32:51 PM PDT by Al Simmons
In the 1993 movie Jurassic Park, one human character tells another that a Tyrannosaurus rex can't see them if they don't move, even though the beast is right in front of them. Now, a scientist reports that T. rex had some of the best vision in animal history. This sensory prowess strengthens arguments for T. rex's role as predator instead of scavenger.
Scientists had some evidence from measurements of T. rex skulls that the animal could see well. Recently, Kent A. Stevens of the University of Oregon in Eugene went further.
He used facial models of seven types of dinosaurs to reconstruct their binocular range, the area viewed simultaneously by both eyes. The wider an animal's binocular range, the better its depth perception and capacity to distinguish objectseven those that are motionless or camouflaged.
T. rex had a binocular range of 55, which is wider than that of modern hawks, Stevens reports in the summer Journal of Vertebrate Paleontology. Moreover, over the millennia, T. rex evolved features that improved its vision: Its snout grew lower and narrower, cheek grooves cleared its sight lines, and its eyeballs enlarged. ...
Stevens also considered visual acuity and limiting far pointthe greatest distance at which objects remain distinct. For these vision tests, he took the known optics of reptiles and birds, ranging from the poor-sighted crocodile to the exceptional eagle, and adjusted them to see how they would perform inside an eye as large as that of T. rex. "With the size of its eyeballs, it couldn't help but have excellent vision," Stevens says.
He found that T. rex might have had visual acuity as much as 13 times that of people. By comparison, an eagle's acuity is 3.6 times that of a person.
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T. rex might also have had a limiting far point of 6 kilometers, compared with the human far point of 1.6 km. These are best-case estimates, Stevens says, but even toward the cautious end of the scale, T. rex still displays better vision than what's needed for scavenging.
The vision argument takes the scavenger-versus-predator debate in a new direction. The debate had focused on whether T. rex's legs and teeth made it better suited for either lifestyle.
Stevens notes that visual ranges in hunting birds and snapping turtles typically are 20 wider than those in grain-eating birds and herbivorous turtles.
In modern animals, predators have better binocular vision than scavengers do, agrees Thomas R. Holtz Jr. of the University of Maryland at College Park. Binocular vision "almost certainly was a predatory adaptation," he says.
But a scavenging T. rex could have inherited its vision from predatory ancestors, says Jack Horner, curator of paleontology at the Museum of the Rockies in Bozeman, Mont. "It isn't a characteristic that was likely to hinder the scavenging abilities of T. rex and therefore wasn't selected out of the population," Horner says.
Stevens says the unconvincing scene in Jurassic Park inspired him to examine T. rex's vision because, with its "very sophisticated visual apparatus," the dinosaur couldn't possibly miss people so close by. Sight aside, says Stevens, "if you're sweating in fear 1 inch from the nostrils of the T. rex, it would figure out you were there anyway."
Stevens, K.A. 2006. Binocular vision in theropod dinosaurs. Journal of Vertebrate Paleontology 26(June):321-330.
Stick with your day job, if you have one. You aren't funny.
The issue here is you are stalking another freeper after he has declined to answer a personal question. It is not a question related to the science topic that started this thread.
I can be obnoxious, but I have been here eight years without pushing the abuse button for anything posted to me. I can take anything I dish out, and more.
People who utter their beliefs are not truely faithful.
Oh well, carry on with the flying brickbats...
Page back and word search for Knock it off!
That was to ballrog666 yesterday, wasn't it??? 'GOD''s post doesn't count... *LOL*
and, if someone actually takes the time of learn something from the articles, it makes it worthwhile....
Whoops! I thought I was pointing you to Carolina(something). Must have been on another thread.
Keep posting. I do learn from the articles.
Don't mention it. I have developed a growing "CREVO" ping list that is about 50/50 from each side, guaranteeing a brawl every time....I get some of these articles from the Dinosaur Mailing List, where these 'Crevo' discussions are verbotten...its just for palaeontologists (and amateur wannabes)....
"If T-Rex was a vegetarian, as Hovind asserts, it was certaintly not a predator."
T-Rex might have been a lot of things, but I don't think vegetarian fits anywhere.
"Thanks for proving to everyone on the forum that you're a whacko. LOL!"
Whacko? Pointing out self-righteousness in our friends from Team Zap isn't proving Whacko. Now, believing everything was Zapped all at once in its present form, well, that is suspect.
You wouldn't accuse Saint Kent of being a fool, would you?
Does he think T-Rex was a vegetarian? If so, yes.
Oh brother, STALKING? I have done no such thing. FYI, O.F. and I have gone round and round on another thread before. I've merely called him out to state his beliefs after his nasty remarks toward theists.
I see right through your smoke screen. You're trying to justify your unwarranted attacks on me by making a bogus claim. Thanks, but I believe OmahaFields is capable of taking care of himself and doesn't need you to make up lies. I'm not easily intimidated, so give it up.
I can be obnoxious, but I have been here eight years without pushing the abuse button for anything posted to me. I can take anything I dish out, and more.
I noticed you didn't mention how many times people have pushed the abuse button ON YOU. Getting a little paranoid after admitting you attacked me, aren't you? If anyone is being abusive here, it is you. In fact, I'll add to our little record of correspondence on this thread and ask that you please leave me alone and not post to me again. I'm sure you'll honor my wish since you wouldn't want to stalk me.
Hitting the hard stuff this morning, I see.
Dictionary definition of utter:
To articulate (words); pronounce or speak
One of these days you'll re-read your ridiculous statements and want to crawl in a hole. Maybe today?
"Hitting the hard stuff this morning, I see."
Not enough to see any miracles. Just reality.
Psssst: It really is pathetic when one feels he has to bash another's religion in order to feel superior.
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