Crazy Zoologist :

Владислав, верно у кроно челюсти посильнее. Но непонятно сильнее ли чем у дейнозуха и тем более пурусзавра. Но то что они лидеры это ясно. Думаю никто не кусал сильнее.

Мое мнение кронозавр с черепом 240см был чемпион по силе челюстей ,если конечно они у него шире чем у пурусзауруса !

Кронозавр с 2 метровым черепом был 12 метров  вдлину. А эти новонайденные гиганты с 3метровым черепом максимум 15 метров, ну 16 как потолок, не больше.

Vladislav :

Мегалодон :

Vladislav, возможно это так, но я ещё раз повторюсь, что по многим источникам размер лиоплеврадона был именно таким. Этим я хочу сказать, что мне нет интереса вас обманывать или возвышать какое - либо из этих замечательных животных.

Приведите пожалуйста источник где это указывается. А то я всегда считал что лиоплевродон достигал 15-ти метров в длину. Тем не менее я считаю что лиоплевродон достигал именно 15 метров в длину. Кронозавр с 2-х метровым черепом, наверно был ещё больше.

например, вот один из источников - Короли мезозоя. Следующие источники перечислю, когда буду дома, ато я не помню как называются эти книги.

Череп типового вида Liopleurodon ferox - около 1,5 м в длину, общая длина по разным оценкам - от 7 до 10 м. Нижняя челюсть Liopleurodon macromerus (синонимы: Pliosaurus macromerus, Stretosaurus macromerus) достигала в длину более 3 м (сохранился фрагмент длиной 2,875 м), а само животное могло достигать 15 м в длину. Остатков плиозавров длиной 25 м, какие показаны в "Прогулках с динозаврами", не найдены! (см. Plesiosaur Site).

Почему? Написано же что череп самого крупного лиоплевродона - более 3 метров, а череп кронозавра по-моему 2,7 метра, до 3. Но кронозавр имел более массивне кости.
Так что максимум для лиоплевродона 15 метров. А длину кронозавра я вычислял 12 с чем-то метров. Там больше 13 не получается.

Humans Have a Mighty Bite, New Research Shows

ScienceDaily (June 21, 2010) — The robust jaws and formidable teeth of some of our ancestors and ape cousins may suggest that humans are wimps when it comes to producing a powerful bite: but a new study has found the opposite is true, with major implications for our understanding of diet in ancestral humans.

The surprise findings suggest that early modern humans did not necessarily need to use tools and cooking to process high-nutrient hard foods, such as nuts -- and perhaps less tough foods such as meat -- but may have lost an ability to eat very tough items, such as tubers or leaves.

In the first comparison of its kind, Australian researchers have found that the lightly built human skull has a far more efficient bite than those of the chimp, gorilla and orang-utan, and of two prehistoric members of our family, Australopithecus africanus and Paranthropus boisei.

They found that modern humans can achieve relatively high bite forces using less-powerful jaw muscles. In short, the human skull does not have to be as robust because, for any given bite force, the sum of forces acting on the human skull is much less.

These results also explain the apparent inconsistency of very thick tooth enamel in modern humans -- a feature typically associated with high bite forces in other species. Thick enamel and large human tooth roots are well adapted to take high loads when biting.

The study appears in a paper in the journal Proceedings of the Royal Society B by a team led by Dr Stephen Wroe, of the Computational Biomechanics Research Group in the UNSW's School of Biological, Earth and Environmental Sciences. They used sophisticated three-dimensional (3D) finite element analysis to compare digital models of actual skulls that had been CAT-scanned.

The technique, adapted from engineering, provides a highly detailed view of where stresses occur in materials under loads designed to mimic actual scenarios. Wroe's team has previously used this approach to study the jaw mechanics of living and extinct species as varied as the great white shark and the sabre-toothed tiger.

These result calls into question previous suggestions that the evolution of a less robust skull in modern humans involved a trade-off for a weaker bite or was necessarily a response to behavioural changes, such as switching to softer foods or more processing of foods with tools and cooking. It has also been suggested that human jaw muscles were reduced to make way for a larger brain.

"However plausible those ideas may seem they have been based on very little by way of comparative data: for example, there are no actual records of bite force collected from living members of any other ape species, " says Dr Wroe. "It turns out that we don't have a wimpish bite at all -- it is very efficient and powerful.

"When we're biting down in vertical plane, at the back of the jaw our bite is about 40-50% more efficient than it is for all great apes. It's even more efficient when biting at the front of the jaw.

"We've only looked at two extinct hominins in this study, but, for our size, we humans are comparable in terms of maximum bite force to these fossil species, which include 'nutcracker man', renowned for its particularly massive skull and jaw muscles. Size matters, but efficiency matters more -- and humans are very efficient biters.

"Importantly though, our study focuses on the generation of peak bite forces over short time spans. The jaws of other species may be better adapted to maintain chewing over long periods. This means that although humans are up there with great apes in their ability to quickly crack open a hard item, such as a large nut, or process less tough foods, such as meat, they may be less well adapted to process tough material, such as leaves or bamboo, which requires sustained chewing over a long period."

The study team included UNSW colleagues Toni Ferrara, Darren Curnoe and Uphar Chamoli, along with Colin R. McHenry of the University of Newcastle, and was supported by the Australian Research Council.

--------------------------------------------------------------------------------

Journal Reference:

S. Wroe, T. L. Ferrara, C. R. McHenry, D. Curnoe, U. Chamoli. The craniomandibular mechanics of being human. Proceedings of the Royal Society B: Biological Sciences, 2010; DOI: 10.1098/rspb.2010.0509


Comparison of human and other primate skulls. Colors indicate degrees of stress on bones and teeth.

http://www.sciencedaily.com/releases/20 … 095116.htm

Human Bite Force Compares to Chomp of Chimps

By Charles Q. Choi, LiveScience Contributor
posted: 22 June 2010 05:19 pm ET

Humans are often considered wimps compared with our strong-jawed relatives, but now scientists find that our bites might be far mightier than before thought. Relative to our size, humans could chomp down with as much force as a chimpanzee or even the so-called huge-jawed extinct "nutcracker man."

One of the key traits that mark the beginning of the human lineage, other than upright postures and larger brains, are smaller teeth. Still, oddly, we possess very thick tooth enamel, a feature typically linked with strong bites.

Now researchers find that although modern humans possess smaller teeth and jaws than our closest relatives, both living and extinct, we have surprisingly powerful bites.

Although the human skull is relatively lightly built, Australian scientists found that our jaws are at least 40 percent more efficient than those of the chimp, gorilla and orangutan, and of two prehistoric members of our family, Australopithecus africanus and Paranthropus boisei — the latter nicknamed "the nutcracker man" for its especially massive skull and jaw muscles.

"For our size, we humans are comparable in terms of maximum bite force to these fossil species," said researcher Stephen Wroe, a biomechanist and paleontologist at the University of New South Wales in Sydney, Australia. "Size matters, but efficiency matters more, and humans are very efficient biters."

The scientists developed sophisticated 3-dimensional computer models from actual skulls they CAT-scanned, including one from an African bushman hunter-gatherer that might better reflect what ancient humans might have been like than a living person. These simulations provided highly detailed views of where stresses occur in materials in scenarios designed to mimic real life, a technique Wroe and his colleagues have previously used to study the jaws of a number of living and extinct species, such as the great white shark.

The efficiency of human jaw muscles explains why our skulls are not as robust as our relatives, since our skulls undergo much less stress. Our powerful bites also help explain why our tooth enamel is so thick.

Although our bites are more efficient overall, some of our relatives nevertheless had stronger bites than us simply because they are larger — for instance, gorilla bites could generate forces 30 percent to more than 50 percent greater than ours. Also, while human bites are comparable to our relatives in terms of being able to quickly bite down to crack open hard items like nuts, we may be less capable of consuming tough foods, "such as leaves or bamboo, which require sustained chewing over a long period," Wroe said.

These findings shed new light on how we might interpret the evolution of human diet and growth. Some possibilities that scientists had suggested in the past for our small teeth and jaws included a switch to softer foods, more processing of foods with tools and cooking, or a shrinking of our jaw muscles to make way for larger brains.

"However plausible, those ideas may seem they have been based on very little by way of comparative data — for example, there are no actual records of bite force collected from living members of any other ape species," Wroe said. "We've done detailed 3-D comparisons here for the first time and, as it turns out, modern humans don't have a wimpish bite at all — it is very efficient and powerful."

The scientists detailed their findings online June 22 in the journal Proceedings of the Royal Society B.

http://www.livescience.com/health/human … 00622.html

Интересно бы узнать каков укус был у тилозавра. Ведь он питался крупными рыбами и эласмозаврами. Челюсти должны быть не сильнейшими, но примерно как у лиоплевродона.

Понятно.
Попробую сложить топ 6 сильнейших доисторических челюстей:
1) Дейнозух, пурусзавр, кронозавр.
2) Лиоплевродон.
3) Саркозух,Мегалодон.
4) Тираннозавр.
5) Базилозавр.
6) Мозазавр Гофмана.
Что скажете?

Отредактировано Vladislav (28 June 2010 16:03:37)

У косатки сильнее чем у крокодила. Не известна сила сжатия челюстей бегемота. У крупного тигра думаю посильнее чем у гиены.

А слон? Сила сжатия у него явно больше чем у волка.

Так арбуз все раздавить могут у кого он во рту помещается.
В списке многих хищных нету - креодонтов, перкрокутид например. А где медведи, амфиционы?
Диноцион кусал явно сиьнее современных гиен.

Ещё очень сильны были у пещерного медведя и агриотерия.
И нет в списке эндрюсарха. Нет гигантского амфициона, диноциона...