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Post by arioch on Dec 30, 2008 20:25:15 GMT
Invalid argument for me.
The owls had feathers in the legs and all around the beak, and they use both to kill.
Also, you know if the fight betwen the raptor and his prey were normally so long that the predator were in high risk to be hurted?
You cant judge this for the single fossil velociraptor-protoceratops, where probably the raptor was defending himself after being catched stealing eggs from the nest. In real nature, predators only hunt those who can kill easily and fast, that what not implies a dangerous struggle. In the case of dromaeosaurids: ambushes, grabs with hands, feet claws rips the torso, game over. No long struggle. Their builds were too fragile to allow them to do that. Thats the way to hunt, or they would be innefective predators.
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Post by [][][]cordylus[][][] on Dec 30, 2008 20:30:03 GMT
The dromeaosaurid sickle claws didn't rip. They just stabbed, like knives. A study was done to see how effective the claws would be at disembowling, and I think one of the claws even broke.
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Post by arioch on Dec 30, 2008 20:37:05 GMT
Wathever, rip, stab.... They used it to kill, and they need to do it fast, or they were dead meat. They didnt have builds prepared to fight anything bulkier than themselves, without the advantage of ambush.
By the way, now i remember that study from a documental (with a a robot replica, right?). And, anybody thougt there in the wearing for erosion in the claw, or the bone recovering on the claws in life, that could be in fact sharped (like happens in some present carnivores-?
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Post by [][][]cordylus[][][] on Dec 30, 2008 20:45:41 GMT
^ Or a pack. If they hunted in packs, they could hunt things much larger than themselves, like that "deinonychus vs. tenontosaurus" fossil, where there were a bunch of deinonychus and one tenontosaurus.
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Post by arioch on Dec 30, 2008 20:59:52 GMT
There are no proof about the hunting in packs. Also, we know the brain shape of a theropod ressembles too much the crocodile one. And crocs are solo hunters, and smarter that most people think, by the way. Theres no living relative of dinosaurs ,in birds or reptiles, that hunt in packs. Crocs lives in groups, but thats all. Komodo dragon fed in group, but hunts alone. Thats probably what happened with the tenontosaurus and deinonychus, they just found the corpse and started the banquet. And, c´mon, animals who weights less than a human, chasing animals of several tones? thats like expecting wild african dogs chasing elephants. Its ridiculous. I´m not angry , eh .
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Post by [][][]cordylus[][][] on Dec 30, 2008 21:00:34 GMT
And there also isn't any "proof" that most dromeosaurids had feathers, but most people still assume they do.
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Post by arioch on Dec 30, 2008 21:39:02 GMT
We have some fossil feather impressions, we have cladistics and we have our logic. For some experts, this is enough.
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Post by [][][]cordylus[][][] on Dec 30, 2008 21:57:52 GMT
We have the sizes of some dromeosaur brains, and they seem to be pretty smart. For some experts, this is enough to assume that some of them hunted in packs.
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Post by sid on Dec 30, 2008 22:48:48 GMT
We have the sizes of some dromeosaur brains, and they seem to be pretty smart. For some experts, this is enough to assume that some of them hunted in packs. I agree with that theory...Even if judgin' the intelligence of a certain animal ONLY considering the size of its brain is mostly wrong and kind of "antropocentric",i tend to think that Raptors were probably pack hunters,just like (maybe) Allosaurs and some other theropods...
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Post by arioch on Dec 30, 2008 22:53:18 GMT
That would not be experts in biology.
The only known animals who hunt in packs are mammals. In the other hand, we know a lot a bird-like animals, living and extinct , who have feathers, including, er...birds.
Parrots have a big brains for their size, too, and see what theyre able to do.
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Post by [][][]cordylus[][][] on Dec 30, 2008 23:43:38 GMT
"that would not be experts in biology"
Then who are your experts, Mr.? I want names! ;D
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Post by stoneage on Dec 31, 2008 0:28:31 GMT
Yes, it doesn't make sense to me how a large Dromeosaurid like Utahraptor or Deinonychus would have large feathers on their forearms. They most certainly didn't fly, and claw marks tell us that they used their teeth, toe claw, and hands when fighting. Like sid said, they would have been easily damaged. I'm not against large Dromeosaurs having some sort of feather like structures somewhere on its body, but the arms sound odd. Then again, the feathers could have been stronger then the feathers of today, or the Raptors may have been careful not to damage them during a fight. ;D How do claw marks tell you they used their teeth? How can you be careful about y6our feathers when your in a fight? The important thing is winning the fight, cosmetics are less important! ;D
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Post by itstwentybelow on Dec 31, 2008 3:06:21 GMT
That picture reminds me of old reconstructions of hypsilophodon as a tree-dweller. Reconstructions which were incorrect. There is no evidence to suggest arboreal life for dromaeosaurids, and I think one thing that should be obvious is the size of Utahraptor. It was far too big to have been a tree-dweller, yet its anatomy closely resembles other dromaeosaurids like velociraptor and deinonychus, only much bigger. To me, that says that these animals were not adapted to an arboreal lifestyle. They were adapted for running and hunting on solid ground. There is also a lot of evidence to suggest pack behavior, which is often not found in a tree-dwelling predator. A leopard will drag a kill up a tree to protect it, but leopards are solitary animals. A pack of wolves keeps a kill on the ground so the whole pack can feed. I envision a raptor's behavior would have been similar to a wolf.
Sorry arioch, but the tenontosaurus find was pretty clear evidence for pack behavior in Deinonychus. Even if the Tenontosaurus was already dead, the fact that there were many Deinonychus feeding from it indicates social behavior. Solitary predators would never have tolerated the presence of others feeding from their own carcass, so this shows that there MUST have been cooperation between these individuals. You also have to keep in mind that dinosaurs were unique animals. Even though they were related to both reptiles and birds, there is nothing quite like a dinosaur alive today, so saying that there are is no modern pack behavior in reptiles or birds is pretty much irrelevant to determining dinosaur behavior.
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Post by kuni on Dec 31, 2008 3:29:23 GMT
20below: I'll agree with Utahraptor probably being too large to climb effectively (though it IS lightweight and has those wonderful climbing-piton talons), but wing-assisted incline running could have allowed small dromaeosaurs to quickly scale trees and cliffs, with the large feathers reducing the stress of falls. The Tenontosaurus find, interpreted strictly, does suggest a behavior more similar to the Komodo dragon, given that several of the Deinonychus appear to have been subadults killed by larger Deinonychus, a behavior much more similar to varanids than canids, which have considerable phylogenetic distance to dromaeosaurids. That being said, birds DO exhibit cooperative hunting, check out this article: findarticles.com/p/articles/mi_m1200/is_/ai_6540261 . If some birds do it, it's not at all unrealistic to suggest that this behavior existed in dromaeosaurids. It wouldn't shock me in the least if many dromaeosaurids were social - the most striking evidence of this is a group of tracks purported to be from a group of Unenlagia moving in one direction with individuals seperated by about a meter. However, modern "raptors" like eagles and owls are often solitary predators, so it is likely that not all dromaeosaurids were pack hunters. Holtz suggests that Velociraptor is unlikely to have been a group hunter, given that it lived in a desert environment, which would have made it difficult to support a large "raptor pack". I wonder if maybe some feathered raptors had bright colors on the undersides of their arm feathers. The animals could display to other group members or use them as sexual signals, but they could also flash them in the face of a prey animal to startle and confuse it, and keep it from running away from the raptor pack.
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Post by arioch on Dec 31, 2008 12:44:10 GMT
Sorry arioch, but the tenontosaurus find was pretty clear evidence for pack behavior in Deinonychus. Even if the Tenontosaurus was already dead, the fact that there were many Deinonychus feeding from it indicates social behavior. Solitary predators would never have tolerated the presence of others feeding from their own carcass, so this shows that there MUST have been cooperation between these individuals. You also have to keep in mind that dinosaurs were unique animals. Even though they were related to both reptiles and birds, there is nothing quite like a dinosaur alive today, so saying that there are is no modern pack behavior in reptiles or birds is pretty much irrelevant to determining dinosaur behavior. You´re not reading properly. I never spoke about solitary predators. They could be creatures who lived in groups but hunted alone, like crocodiles. Who, also shared his food after kill the prey alone, like Komodo dragons. And this is the most probably, because, apart from being relatives (take a look on clades, dinosaurs are not "completely different" to present animals), the brain shapes were almost the same. The tenontosaurus fossil proves nothing. A river current could dragged the corpses there. Theres alot of explanations , and the pack hunt is one of the weakest... Theres any sign of deinonychus claws or teeth in tenontosaurus bones. Also, if they were so efficient in pack, why so many died in the hunt? That article is quite interesting, but it really dont contribute to prove something of what you say. Its a unusual bevaviour motivated for the need of adaptation and survival of that hawks. And, there says that just one hawk kills the rabbit, while the rest just desorientate him flying around. In some ways it is still solo hunting.
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Post by kuni on Dec 31, 2008 17:00:43 GMT
That article is quite interesting, but it really dont contribute to prove something of what you say. Its a unusual bevaviour motivated for the need of adaptation and survival of that hawks. And, there says that just one hawk kills the rabbit, while the rest just desorientate him flying around. In some ways it is still solo hunting. Actually it very much does, as it's true social hunting, where others adopt ineffective solo predation strategies in order to ensure that one other hawk makes an effective kill. "Solo hunting" would be a group of hawks all doing an effective solo predation strategy, and success increasing with the number of hawks - crucially but significantly different.
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Post by arioch on Dec 31, 2008 20:43:00 GMT
Theres a big diference between cooperative behaviour (what is not so hard to develop in clever animals), and hunt in packs. The day i see some predator birds atacking all to the same large prey and beat it, i will begin to consider what you say.
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Post by kuni on Dec 31, 2008 22:49:18 GMT
Theres a big diference between cooperative behaviour (what is not so hard to develop in clever animals), and hunt in packs. The day i see some predator birds atacking all to the same large prey and beat it, i will begin to consider what you say. You're very much missing the point -- the hawks and jackrabbits are similar-sized, and the author of the article mentions that a rabbit is likely quite capable of breaking a hawk's bones with a kick. That's similar to raptor vs. hadrosaur - the raptor may have deadly claws but one kick and it's in serious trouble. Also, even though they're not wolves, Harris hawks live and hunt in packs, and in fact, are often referred to as "wolves of the air". Here's a cool video on it: video.nationalgeographic.com/video/player/animals/birds-animals/birds-of-prey/hawk_harris.html(Just admit it, you've lost this one! )
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Post by arioch on Dec 31, 2008 22:57:30 GMT
And you are crashing against the wall of Reality again and again. A protoceratops could break the velociraptor ribs with his strenght, too, and its a prey than just one velociraptor could kill if he use ambush and have luck, like fossil proves (he was in disavantadge, and anyway killed him). They don´t needed a pack for that. I repeat, 2 birds coodinating to kill small prey is not pack hunting. Your insulting real pack hunters with the comparison. Happy new year.
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Post by kuni on Dec 31, 2008 23:26:52 GMT
I repeat, 2 birds coodinating to kill small prey is not pack hunting. Your insulting real pack hunters with the comparison. Please read the article and watch the video - the hawks hunt in family groups of around 5-7 animals, exactly like wolves. They're pack hunters, QED.
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