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.
There has never been a serious claim by scientists that bees, bumble or otherwise, can't fly. It is a fact that insect flight is quite different from airplane flight, or even bird flight.
However, the false claim continues to show up on creationist websites to demonstrate that they have no regard for simple truth.
"creationist websites to demonstrate that they have no regard for simple truth."
I have yet to see provable truth on any creationist website anywhere. Attack science with faith. Doesn't work.
"newbie"
I like it! You just tickled my smiling nerve, so don't go asking for forgiveness or anything. Can I just go by "Noob" instead? That's what all the cool kids call each other on the gaming sites. Are you a gamer?
Quite seriously, if you ever have any evidence to prove any of your points, I'd be happy to take a look and discount them for you. No faith proof though, that doesn't count in the science world.
Gotcha. RR's response is a bit cryptic. I smell a reference to Ted Holden somewhere in this.
I like it! You just tickled my smiling nerve, so don't go asking for forgiveness or anything
Wow, you really are a novice not to know that posting on FR for less than two months classifies you as a newbie. I'm not surprised though. Know-it-alls usually know very little.
Quite seriously, if you ever have any evidence to prove any of your points, I'd be happy to take a look and discount them for you.
Let's start with the fact that you've given evidence in your many posts that you're obnoxious. As I stated before, it really is pathetic when one feels he has to bash another's religion in order to feel superior.
Thanks for giving me info on the geographical details of the sauropod distribution.
Provided the prey species is large enough, however, my other points still hold.
Was the typical hadrosaur large enough for one to feed a T-rex, (or group of velociraptors) or would there be left-overs?
If leftovers, then T-rex would have something worthwhile to scavenge on. I mean, a T-rex most likely wouldn't have been snacking on chipmunk-sized fare; those are teeth in its mouth not baleen.
Cheers!
"Know-it-alls usually know very little."
And the self-righteous know even less.
"Let's start with the fact that you've given evidence in your many posts that you're obnoxious."
Ooohh, did I hit a nerve, Troll?
There is nothing more obnoxious than a Christian who thinks they are the only ones going to heaven. That is the epitomy of obnoxious. Especially when you see the history of what Christians have done to other cultures.
And BTW, I know what "new" is Goob. I just laugh at what point you are trying to make. You being here for a while just proves that you don't mind being wrong alot. Ooops, gotta go, Noob training in 10 minutes.
There is nothing more obnoxious than a Christian who thinks they are the only ones going to heaven.
Oh, so YOU think YOU'RE going to heaven? LOL!
You being here for a while just proves that you don't mind being wrong alot
Another one of your leaps to a wrong conclusion. < / yawn>
>>You have a citation for that? An actual published journal article or something? Or do you just like the sound of wind whistling through your head?<<
You'll have to ask the person that said it. I didn't. It is the remark I was responding to from post 514.
Clever insult, nonetheless. You would be one of the evolutionists, I suspect.
That's already been acknowledged, although I still don't know what your intent was.
>>There has never been a serious claim by scientists that bees, bumble or otherwise, can't fly.<<
Is this some sort of joke? When has anyone said that bees can't fly? There were those that said it "seems to be" impossible, but that is quite different. It just meant we still needed to learn something about a behavior that is obdserved on a daily basis.
I think the previous semantical arguments you were having have successfully moved you to a completely different thought plane. Allow us to catch up. ;)
Sorry, I just came back and was responding in order.
My bad...
The statement about bees keeps popping up as an example of how science is always wrong. The assertion that bees can't fly has never been made in the name of science, although it is true that the mechanics were not understood until very recently.
My point was very narrow, and it was directed to you in error.
"Oh, so YOU think YOU'RE going to heaven? LOL!"
As usual, wrong conclusion. No, I'm not going to heaven. I was condemned to hell by God's little helpers. Brought a tear to my eye.
Are you getting irritated? Try taking a position where you have actual evidence to present. It is much less stressful that way. Anything to say about T-Rex? I know it is hard with no bible verses to direct you. It may just be easier to keep attacking evolution without evidence. Have a nice day, Dem.
" As I stated before, it really is pathetic when one feels he has to bash another's religion in order to feel superior."
I'm not bashing your religion. I'm just telling you straight up, religion and science are two totally different fields. Religion requires no proof. Religion can claim anything, and usually claims superiority over things and people they have no right to. Science takes physical evidence and submits working models for how they came to be, among other things. Evolution is as close to fact as it gets. The fact the Creationists are flip flopping mad and doing anything they can to present false evidence to the contrary shows what a slippery slope they are standing on.
Maybe you need to check out the definition of "bash":
To criticize harshly; To engage in harsh, accusatory criticism.
The fact the Creationists are flip flopping mad and doing anything they can to present false evidence to the contrary shows what a slippery slope they are standing on.
Uh, like I said (for the third time), it really is pathetic when one feels he has to bash another's religion in order to feel superior. I think we're done here.
a. Too heavy to fly, and
b. Could not glide,
why do you suppose that it had bat-like wing membranes between its elongated 5th finger and body?
P.S. Its not 'Brontosaurus', its 'Apatosaurus'...and it had no problem 'lifting its head off the ground', because its neck was reinforced with tendons which kept the neck basically parallel to the ground.....(you might want to rent 'Walking with Dinosaurs'....they did a pretty good job illustrating the most recent wisdom on the subject...)
Ummmm.....I posted that, not Rob Roy, and you darn well know that the technical physics of how bees actually stay aloft was a mystery until fairly recently....
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