Darn, when I saw the last post was from Barney I thought we would get a real dinosaur point of view.
It could do the chicken dance. It did do the chicken dance. It became a chicken. Now, what can chickens do with their wings? Coincidence?
T. Rex probably had reputation for such an ill disposition because he couldn’t masturbate, and when he did try, he looked so stupid and clumsy that the other dinosaurs laughed at him and made fun of him. You do not piss off a frustrated, horny lizard with chompers like that. Did anyone see the movie “Carrie”? It’s based on, IIMTUC, a true T. Rex caught-attempting-to-masturbate incident.
This is probably very rude, and I apologize if it offends anyone, but when I was at Mardi Gras last year, I saw a guy with little T. Rex arms at a bar drinking a beer.
yabob wrote that Jack Horner says:
Which, as far as Jurassic Park and at least one episode of The Learning Channel’s Paleoworld are concerned, is nonsense. T. Rex’s two-legged gait was supposed to allow it to exceed 25 miles per hour.
any chance that T. Rex’s arms are an example of a transitional evolutionary feature? (somewhere between “once used” and “gone”) I’m sure T. Rex used them for whatever it could, but it may have been very limited. I don’t use my little toe for much, but it must help with balance a little.
You might be interested in this story that ran in the Washington Post today: Scientists say a 220-million-year-old tree lizard is the oldest feathered animal ever found, predating the earliest known bird by 75 million years and casting doubt on the prevailing view that birds are descended from dinosaurs.
This is a response to silent_rob: Obviously you’ve lived in the suburbs for too long…
Before we humans came along to put their trash in out for scavanging, there were racoons, and they had to eat SOMETHING. The original poster said that scavanging will happen when/if the opportunity presents itself. His point was that there are no land animals that are strictly scavangers, all carnivores have the capacity for hunting in one way or another.
I’ve seen racoons digging up lawns looking for grubs to eat, that sounds like hunting to me.
Almost all the other examples you use are perfect examples of his point. I’ve got no defense for the rat, that’s the one case were you might be right, but the idea that bears, lions, and leopards? Yeah, they scavange, but they’re also damn impressive hunters.
Hell, half my co-workers walk around looking for remnants of lunch meetings before walking outside to buy something, imagine if we had to hunt first?
c’ya
bouch
You betcha!
Take a look at this monster…it had a HUGE head, filled with HUGE teeth. It also had HUGE feet. These were its killing tools (at least, that’s what the ‘T. rex as hunter-killer’ school feels). That big head, though lighter than one migth think given its size, was still pretty hefty. If the animal had proportional arms as well, it is thought the poor critter would be somewhat front-heavy. To counter-act this sort of thing, as the head grew, the arms shrunk (we’re talking on an evolutionary time-scale here, not a developmental one). The head became the primary tool, and the arms gradually lost their significance. Which is not to say they became COMPLETELY useless. They may still have been used for such things as holding its mate during…mating. At least for the male.
BTW, I met Jack Horner when I was at UC Berkeley (he was doing a sabattical at the time - like me, he drinks a gallon of Coke in the morning, instead of coffee 
). I asked him how therapods might quickly turn in a chase, given their ankles were little more than hinges - that is, they could move up and down, but had little, if any, lateral mobility. He quickly pointed out that he didn’t think most therpods could run fast enough for it to be an issue 
I think that the idea of trying to determine if birds evolved from dinosaurs is misguided. My personal feeling is that it equates to trying to determine if Homo sapiens sapiens evolved from monkeys.
Birds and dinosaurs probably shared a common ancestor that has yet to be discovered, the way Homo sapiens sapiens and monkeys do.
Not so, in my opinion. Homo sapiens sapiens is a specific species (hmmmm…), while birds are an entire group (or ‘Class’, if you’re into Linnaeus). Determining where birds came from is not misguided. While one possibility is that birds and dinosaurs shared a common ancestor, another possibility is that birds evolved from dinosaurs, and yet another, that dinosaurs evolved from birds. The current ‘best guess’ is that birds evolved from dinosaurs. Attempting to find further evidence to support this theory is no more misguided than trying to gather evidence that birds and dinosaurs share a common ancestor.
And, BTW, I think you are confusing ‘monkeys’ with ‘apes’. Humans do not share a common ancestor with monkeys, but they do with apes.
Not that any of this has anything to do with T. rex and its tiny arms…
Of course I did mean apes, and I usually correct people who make the same mistake. I was just paraphrasing creationist doctrine for some reason. Too much time on these boards today, I guess.
I must concur with silent_bob on the terrestrial scavenger issue. There are animals that are scavengers and are not predators, although almost everything scavenges at some point. I would have used more arthropod and nematode examples though, because most of the animals he mentioned are also predators to some extent.
On the T. rex, it’s a little known fact that due to the short length of their arms relative to their height, a popular Jurassic disco dance was ‘YMCH.’
Actually, they do, but you have to go back a lot further than for the man-ape ancestor. About 25-30 million years vs. about 5-7 million years.
My reference for there being no terrestrial scavengers is http://www.dinosauricon.com/taxa/tyrannosauroidea.html
The Cal berkley page at http://www.ucmp.berkeley.edu/trex/specialtrex2.html points out that all scavengers will preditate without saying there are no terrestrial scavengers.
Raccoons and rats are omnivors. They scavenge (especially urban rats and raccoons) but they eat vegitable matter, meat, anything. They are not scavengers. As for hyenas, I was watching a Nova (or something along those lines) on them and they are the most feared predators of smaller (but not really small) wildlife in Africa. The hunt in packs. One or two come from one direction making that laughing like sound they make, and flush the prey twords the silent waiting partners.
True hyenas will scavenge, but so will lions and crocodiles and bears.
I will conceed that some insects are true scavengers but I was quoteing someone who was really talking about vertibrates bit didn’t actually come out and say so.
Yes, and isn’t it true that ALL terrestrial life has a commom ancestor if you go back far enough?
OK. That’s what I was concerned about. There are many Arthropod (insects and terrestrial crustaceans too), Annelid, and Nematode terrestrial scavengers, so I wouldn’t want anyone to get the impression that scavenging is not a viable niche for terrestrial animals.
I think the site you mentioned should have said it was talking about vertebrates. Tsk! Tsk! Shame on them!
Re: birds from dinosaurs
Prior to the feathered lizard discovery referenced above (which, I confess, I have not fully read yet), the preponderance of fossil evidence did indeed point to birds descending from an ancestor within the dinosaur lineage:
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the first birds appear in the fossil record many millions of years after dinosaurs had already become a going concern
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the first birds share a significant number of anatomical traits with therapod dinosaurs
So, the scenario most scientists accept as making the most sense out of these facts is:
dinosaurs appeared in the Triassic, thrived, and diversified
many millions of years later, in the Jurassic, one of the many existing dinos gave rise to two lineages: one evolved into birds, the other evolved into therapods.
So, birds share a common ancestor with T. rex and the other therapods. That ancestor was already a dinosaur. Birds do not share a common ancestor with Triceratops, Stegasaurus, Brontosaurus (Apatosaurus) and the rest, unless you go way back to the beginning of dinosaur times in the Triassic.
Opinions differ. Your mileage may vary.
Actually, it is believed that that ancestor was currently a Therapod as well. Birds descended from the therapod lineage; they are not a ‘sister’ lineage.
Back to the original post:
I thought it might interest a few of you that the ‘mating’ idea for tyrannosaur forelimbs was proposed by H. F. Osborn (the discoverer of T. rex) in 1906, while the ‘using them when standing up’ idea has been around since about 1970. Personally, I think the ‘standing up’ thing is bunk; anyone ever see an ostrich stand up? They do just fine without using arms at all. Granted, there is a bit of a size difference, and some morpholigical differences as well, between a T. rex and an ostrich, but I think the analogy holds.
Persnally, I don’t think the arms served much use at all. The arms were already much reduced (relative to its size), the fingers were apparently on their way out as well (having been reduced in number to only two), and most of what T. rex needed to do (at least, what would normally be done with one’s arms) could have been done with its mouth or feet - rather like birds.
Actually a better analogy than the ostrich would be the extinct New Zealand moa. Ostriches still have quite large wings (for a bird that doesn’t need them), while the moa had none at all.
And it seems to have gotten around dense NZ forests ok… well, until it became extinct anyway.
lol, that seems rather akin to sating “well the engine worked realy well until it exploded.”