How strong are chimpanzees, really? And why?

[BrainGlutton]

I've often heard that a chimpanzee is seven times as strong as a human of equal weight. But the Wikipedia article on chimps -- http://en.wikipedia.org/wiki/Chimpanzee -- says nothing about that; nor does the article on physical strength generally -- http://en.wikipedia.org/wiki/Physical_strength.

If chimps really are that strong, how does that work? Are their bones differently proportioned? Do they have a different level of muscular efficiency?

[bordelond]

Cecil weighs in on the subject (http://www.straightdope.com/classics/a1_001b.html).

[Gary T]

How strong? Very. Why? [i]"Are their bones differently proportioned?"[/b] That's part of it. Here's Cecil's column on the subject: http://www.straightdope.com/classics/a1_001b.html

[alterego]

Finally, when the average strength of the humerus and femur relative to (body mass · bone length) in modern humans is compared with that in chimpanzees and gorillas, the great apes are shown to be stronger. This is consistent with reports of greater muscular strength in apes relative to humans. It also illustrates the utility of mechanically appropriate size scaling of bone structural properties in reconstructing behavioral characteristics from skeletal remains.

Read the article (http://scholar.google.com/scholar?num=100&hl=en&lr=&c2coff=1&client=firefox-a&q=%22Body+size%2C+body+shape%2C+and+long+bone+strength+in+modern+humans%22&btnG=Search) for a lot more detail than I was interested in. (although, no offence to Cecil, it is empirical.)

[Capt. Ridley's Shooting Party]

This strong. (http://www.usatoday.com/news/nation/2005-03-04-chimp-attack_x.htm)

[Fear Itself]

This strong. (http://www.usatoday.com/news/nation/2005-03-04-chimp-attack_x.htm)Oh man, I wish hadn't seen that. Makes my nads hurt just to read about it.

[GusNSpot]

I have heard that the orangutan is the one that is really strong / weight / size of the apes.

YMMV

[scm1001]

"Animal strength
Chimpanzees are different from humans in several obvious ways, one of which is their sheer physical strength. But why are they so much stronger than us?

The answer isn't just sheer muscle bulk. It's also to do with that fact that their muscles work around five to seven times more efficiently than ours. Studies of human and other primates' jaw muscles show that our muscle fibres are far smaller and weaker than those of our cousins - roughly an eighth the size of those seen in macaques, for example.

The reasons for this remain poorly understood, but one contributing factor is the genes that encode myosin, the protein fibres from which muscles are made. Comparison of human and ape sequences for a myosin gene called MYH16 show that all humans have a mutant version of this gene."

from http://www.nature.com/news/specials/chimpgenome/interactive/chimp_interactive_graphic_pf.html

[eviladam, part 2]

chimps are much stronger because of differences in anatomy.

info (http://uts.cc.utexas.edu/~bramblet/ant301/seven.html)

The chimpanzee distal humerus contrasts with the human. The human lacks the robust lateral supracondylar ridge, a high and robust lateral epicondyle, and the steep, sharp, lateral margin of the olecranon fossa . The chimpanzee forearm is relatively long in comparison to humans . Chimp radius and ulna are more curved than in humans and the chimpanzee distal radius has a radiocarpal joint surface that diverges medially. The major differences between human and chimpanzee limbs are contrasts in relative proportion. Chimpanzees have large powerful arms, slightly longer than their very short legs. Human arms are about 70% as long as human legs.

....

Brachiation generally is associated with major alterations in the arm, hand, and thorax. The shoulder joint is positioned laterally and cranially on a barrel-shaped thorax. Robust muscles attach to the sternum, vertebral column, head, and rib cage, stabilizing the shoulder. The more powerful the arm movements, the more robust the stabilizing musculature must be. The clavicle acts a strut to stabilize the shoulder joint against a sternum whose segments unite to form a single bone. This clavicular-sternal joint is very strong and is not easily dislocated. A relatively round head of the humerus reflects a very wide range of motion. Additional elbow strength results from a more distinct separation of the radius and ulna on the articular surfaces of the distal humerus. The olecranon process of the ulna is small, allowing full extension of robust forearms. Brachiators tend to have reduced thumbs. If a thumb is present, it is folded out of the way against the palm where it does not interfere with elongated fingers that hook or snag handholds. The lumbar region of the vertebral column is shortened and stabilized, and a very mobile hip joint allows the foot to grasp anchorage in a wide range of positions.

[bordelond]

"The reasons for this remain poorly understood, but one contributing factor is the genes that encode myosin, the protein fibres from which muscles are made. Comparison of human and ape sequences for a myosin gene called MYH16 show that all humans have a mutant version of this gene."

from http://www.nature.com/news/specials/chimpgenome/interactive/chimp_interactive_graphic_pf.html
Hare-brained speculation:

What if one day in the future, geneticists are able to "correct" this gene in a human embryo? :eek:

[astro]

We're engineered to stand upright and walk/run considerable distances and use tools which seems to have demanded a powerful lower body and a more gracile upper body. I imagine our leg muscles are among the strongest of the primates A lot of the chimp skeletal engineering maximizes upper body strength for tree/forest dwelling.

It would be interesting to test chimpanzee fine motor skills vs humans.

[GargoyleWB]

We're engineered to stand upright and walk/run considerable distances and use tools which seems to have demanded a powerful lower body and a more gracile upper body. I imagine our leg muscles are among the strongest of the primates

Yep. Humans would rule the primate world at soccer.

Just like we tell stories of a chimpanzee effortlessly fighting 3 humans at once, I bet that there are similar campfire stories told by orangutans and baboons in hushed awe about humanity's devastating penalty kick shootouts.

[KlondikeGeoff]

I have heard that the orangutan is the one that is really strong / weight / size of the apes.YMMV

So, how much can one bench press? :)

[awldune]

This strong. (http://www.usatoday.com/news/nation/2005-03-04-chimp-attack_x.htm)

"the chimps also tore off Davis's ... foot."

His FOOT!?! That's seriously freaking strong.

[LiveOnAPlane]

Strength in one area does not necessarily imply that those who do not possess it are inferior. From what I can glean, we are built differently from chimps & apes due to our different hunting styles:

As cursorial hunters we share with dogs a tremendous endurance which more than makes up for the fact that we can't run as fast as most other creatures. (http://indomitus.net/2004/20041220.html)

So, yeah, chimps and the other great apes can kick our butts in a mano-a-mano test of strength. But when it comes to going day after day after day in pursuit of prey, we are gonna shade them there.

Neither is necessarily better, but we each have our "strong points" and sheer muscle strength is only one criterion.

[slaphead]

Hare-brained speculation:

What if one day in the future, geneticists are able to "correct" this gene in a human embryo? :eek:
Dunno, but I suppose a caesarian would be the order of the day. That or some really good drugs.

If you combined it with mighty mouse (http://www.mdausa.org/publications/Quest/q82resup.cfm#protein) style muscle growth factor, you'd probably end up with someone that looked spectacular but would snap their own bones every time they tried to do something.

If anyone wants me I'll be in my secret laboratory, on my secret island.... :D

[matt]

Another thing to consider is that when a selection pressure for an attribute is removed from a breeding population, that attribute tends to disappear. For example, cave insects such as those in the basalt flow tunnels of Hawaii have lost their pigments and eyes, and developed extra-long antennae for feeling their way around in the dark.

At some point in our ancestry, our big brains, opposable thumbs and/or changes in habitat made being super-strong just plain irrelevant, or even disadvantageous. Sure chimps can kick our unarmed asses one-to-one, but give us a few spears and bows and they're out of the game. Plus we can hunt buffalo and bison and mammoth and cave bear, so we end up with a lot more food, which means we can outbreed them and so outnumber them.

[Rucksinator]

Hare-brained speculation:

What if one day in the future, geneticists are able to "correct" this gene in a human embryo? :eek:

Maybe those sci-fi movies about genetically-engineered super-strong humans aren't very far off?

[Spectre of Pithecanthropus]

At some point in our ancestry, our big brains, opposable thumbs and/or changes in habitat made being super-strong just plain irrelevant, or even disadvantageous.

IIRC it takes a lot of nutrition to maintain those superdense muscles and sturdier bone structure. At the same time, it also takes a lot to keep our large brains going, so that's where the resources get allocated, in humans.

slaphead, would that necessarily be so about the bones not being strong enough to support the muscle? Since the muscular-skeletal system develop from the same embryonic cells, isn't it possible that the the gene in question would also provide for sturdier bone? Or a related gene elsewhere on the strand?

[Spectre of Pithecanthropus]

Plus we can hunt buffalo and bison and mammoth and cave bear, so we end up with a lot more food, which means we can outbreed them and so outnumber them.

If all those megafauna had been able to talk with one another, one can imagine what they would have said about our forebears:

"They're much more dangerous than you would think. Do NOT mess with them, and run the other way if you see a group of them coming at you."

[matt]

IIRC it takes a lot of nutrition to maintain those superdense muscles and sturdier bone structure. At the same time, it also takes a lot to keep our large brains going, so that's where the resources get allocated, in humans. Yup, compared with reptiles and amphibians and fish, mammalian energy budgets are shocking. So much so that our bodies will even atrophy our feeble muscles to save energy if we reduce the amount of work we do with them.

I wonder if anyone knows the calorie requirements to keep chimpanzees healthy?

[Critical1]

you'd probably end up with someone that looked spectacular but would snap their own bones every time they tried to do something.




not likely, human weight lifters have denser bones due to the extra loads they put on them, I see no reason a human with the crazy monkey muscle gene wouldnt simply develope desnser bones to go alone with them.

[Raguleader]

not likely, human weight lifters have denser bones due to the extra loads they put on them, I see no reason a human with the crazy monkey muscle gene wouldnt simply develope desnser bones to go alone with them.

Yeah, your bones bulk up along with your muscles, but they tend to take longer to do it. If you go from being relatively sedentary to being suddenly very active one of the risks you face is that of stress fractures, where your bones literally start to crack from the sudden pressure put upon them by all your moving around. It's one reason you're supposed to gradually transition into a workout routine, so your bones can catch up (along with your muscles, your cardiovascular system, your metabolism, etc.)

[slaphead]

not likely, human weight lifters have denser bones due to the extra loads they put on them, I see no reason a human with the crazy monkey muscle gene wouldnt simply develope desnser bones to go alone with them.
Hmmmm - good point, although in this thread we have been discussing increases of muscle efficiency by 5-7 times. I seem to recall that the mouse growth factors generated something like 40% more muscle. If those two were to combine in a scalar fashion, you'd be looking at 7-9.8 times more muscle power. So instead of the record for an unaided bench press being 700 or so pounds, you' be looking at muscle capable of pressing something like 4900-6860 lbs, but without any of the skeletal adaptations mentioned by eviladam, part 2.
Bearing in mind that it's not unheard of for dedicated arm wrestlers, bodybuilders and the like to generate enough torque to snap their own bones or rip their muscles loose, I thought the human skeleton simply wouldn't be able to cope with that amount of force input, and the joints and muscle attachment points definitely wouldn't.
However, I have been wrong many, many times, so I will happily defer to those with more knowledge of this (i.e. pretty much anybody) :cool:

[Schuyler]

Bearing in mind that it's not unheard of for dedicated arm wrestlers, bodybuilders and the like to generate enough torque to snap their own bones or rip their muscles loose, I thought the human skeleton simply wouldn't be able to cope with that amount of force input, and the joints and muscle attachment points definitely wouldn't.
However, I have been wrong many, many times, so I will happily defer to those with more knowledge of this (i.e. pretty much anybody) :cool:

I remember back in the day, Brian Bosworth (http://en.wikipedia.org/wiki/Brian_Bosworth) was considered a hot prospect out of college (reading the Wiki link, I guess a really hot prospect). Injuries cut short his professional football career - my understanding was that steriod use allowed his muscular development and strength to overpower his attachment and support structure.

So, I would think that there are limits to how strong humans could get, at least in the short-term, before ripping ourselves apart. Ever wonder how the six million dollar man could throw a car - his super-powered arm was attached to a normal spine; I would have thought he'd rip that bionic arm out by the roots.

[BrainGlutton]

Maybe those sci-fi movies about genetically-engineered super-strong humans aren't very far off?

Maybe, maybe not. A while back we had a CS thread on the subject -- http://boards.straightdope.com/sdmb/showthread.php?t=275033 -- and the consensus was that, given the basic human anatomical structure, it probably would be impossible to gene-engineer a human as strong as Superman, or even Spider-Man.

[Rucksinator]

Maybe, maybe not. A while back we had a CS thread on the subject -- http://boards.straightdope.com/sdmb/showthread.php?t=275033 -- and the consensus was that, given the basic human anatomical structure, it probably would be impossible to gene-engineer a human as strong as Superman, or even Spider-Man.

I was actually thinking more along the lines of soldier or Universal Soldier (that's really more about reanimation than genetics, so it might not count) or the TV show with Jessica Alba, or maybe even Dr. Moreau's Island (?sp?); not comic book superheroes. There are probably many others from the ~70's era along those same lines.

[BrainGlutton]

I was actually thinking more along the lines of soldier or Universal Soldier (that's really more about reanimation than genetics, so it might not count) or the TV show with Jessica Alba, or maybe even Dr. Moreau's Island (?sp?); not comic book superheroes. There are probably many others from the ~70's era along those same lines.

Yes -- but all those assume it is possible to greatly enhance human physical strength without any basic alterations in human anatomy and without mechanical assistance. And it is probably not possible, even with genetic engineering or some functional equivalent of it.

[bouv]

slaphead, would that necessarily be so about the bones not being strong enough to support the muscle? Since the muscular-skeletal system develop from the same embryonic cells, isn't it possible that the the gene in question would also provide for sturdier bone? Or a related gene elsewhere on the strand?

Unlikely, The gene in question, if we are to believe scm1001 and his link, controls the myosin in the muscles, which has nothing to do with bones. Myosin is one of the two proteins that, for lack of a better word, pull along each other to contract a muscle. More myosin (and it's counter part, actin) means stronger muscles. So chimps problaby have more myosin and actin, in addition to the non-mutant version that we have.