Man is able to balance his walk by just 2 legs whereas most animals need 4... Why?
482129
it is aquestion of anatomy.  humans are mammals and we evolved from 4 legged animals.  apes also can walk on two legs but we have adapted further because our pelvis has evolved into a more upright posture with the hip joints facing dowmwards and is more shorter, to allow attachment of the ligaments and muscles that are neccessary for this walking mode.  our spine also has the s bend curvature to give the shock absorber effect.  if u look at mammal skeletons u can see these differences.  the abilty to walk upright and maintain coordination is enhanced by the growth in the frontal lobe of the brain cerebral cortex.
187995
Clearly balance, notice how it's always the opposite hand and foot moving?  Yes, you can walk with your hands at your sides, but it is more awkward and eventually is more inefficient.
860345
No, they aren't.\n\nHumans have a stronger preference for one hand over the other than other animals. That is thought to be due to language being localized on one side of the brain, so motor control gets unevenly dominant (your right side of the brain controls your left hand). Animals don't have the languge skills, and tend to use both paws about equally.
738950
"Balance" isn't much of an explanation.  Why is a big toe better than a small toe?  If big toes produced better balance, then why does it help to have it on the inside, rather than the center of the foot or the outside?  Why not 5 big toes on each foot?\n\nA better explanation is that it is an evolutionary throwback to the "thumb" on the foot of primates.  A lot of the internal bone structures, muscles, ligaments, and nerves of the foot provide further evidence.  Four examples (among many):\n\nFact 1: Look at your hand.  Notice that you have one fewer bone (one fewer joint) in your thumb than in your other fingers.  The same is true in your foot (see picture of foot bones in Source 1) ... your big toe has one fewer bone (one fewer joint) that your other toes .  And the same holds with all primate hands and feet.  Your big toe is a re-purposed "thumb".\n\nFact 2: There is a vestigial muscle in the calf of humans, called the 'plantaris' muscle.  (See source 2.)  It is completely useless in humans ... in fact it is so useless that it is a favorite to be harvested by surgeons needing tissue for reconstructive surgery (like heart surgery), and in fact 9% of humans are born without any plantaris muscle at all.  However, the same muscle is very important in other primates, as it is what lets them flex and oppose the large inside digit of the foot, to allow GRASPING WITH THE FEET.\n\nFact 3: Why is your thumb fatter than your other fingers?  Because it needs to be stronger than the other fingers to be opposable for grasping.  That is the reason the big toe is fatter  than the other toes.  It had to be fatter because it was once used for grasping.\n\nFact 4: Wiggle your toes.  Notice that you can wiggle your big toe independently of your other toes ... but it's very dificult to wiggle any other toe by itself (some people can wiggle their pinkie toe by itself).  The reason for this is that there are more nerves and muscles dedicated to the big toe than to your other toes ... again, evidence that the big toe was once used for grasping.\n\nYes, the human big toe (once we became ground walkers, and no longer grasped things with our feet) has moved forward help the other toes produce better balance when walking upright ... but that doesn't explain why there was a big toe in the first place.
175
According to a column that I read written by Joël Carbonnel, "Nature has never been able to count above five."\n\nA researcher has discovered that when the limbs have more than five digits they become distorted into a bow-legged shape which seriously interferes with normal walking or running.\n\nhttp://www.positivehealth.com/permit/Articles/Regular/joel74.htm
278058
I've never been one to be great at the weird math questions or riddle questions like this but here's what I think: All humans have one head and all horses have one head. Therefore, no matter how many legs you have since some humans and horses are amputees, you have 35 horses and 35 humans. Everyone has one head but not everyone has both legs or even one leg. I hope this helps!
39534
Humans\nThey walk on 4 legs in the morning(crawling as a baby)\n2 legs in the afternoon (As an adult)\n3 legs in the evening (with a cane when old)\nIt is the riddle of the sphinx...
800165
Assuming I'm basically continuing as an upright-ambulating critter.... ?   Rather have a nice flexible tail, which might double as a separate grasping "hand" on occasion.  Although I can't imagine a tail that would handle my bulk, because of being "built for comfort, not for speed"....but it could be a fashion statement....  \n\nCan't see where I might need that much flexibility in my feet---the way I balance, FORGET standing one-legged and bringing up the extra foot-hand....!\n\nToo bad your question option didn't include "an additional, and separately functioning brain" versus "two additional, functional arms and hands".  (grin)  I'll take BOTH of those, ty very much
368677
maybe because they are less agile than that of a smaller animal there by needing only to consume such quantity of food, and also bigger animals has the ability to conserve energy in their body......i guess
828421
Animals are supported by a skeleton, made of bone.  Plants don't have skeletons, they use a cell wall to give them support.  Such walls wound make movement impractical.
47017
There are many at your local animal shelter.\n\nMost of them may actually have 4 legs, but it's easy to remove them.
559447
assuming the one chicken is unique and all other chickens have two legs, 2 1/2.\n\nif all chickens have 1 1/2, then 1 1/2 plus 3/4 would be a total of 2 1/4 legs.\n\nHow does a chicken walk with 1 1/2 legs?
492314
That's the classic dog theory and yes, some men never grow out of that thinking.  Unfortunately, these men lose out on love and end up on their death bed with regrets.  Most women like four-legged dogs, but the two legged ones have trouble walking!!!!!!!
37126
Man - In the morning of their life, they crawl (4 legs), in the noon of their life, they walk (2 legs), and in the evening of their life they need a walking stick, (3 legs).
257123
yeah, defenitley. i've seen it on tv. it was this one doggy that had cancer and had to had his legs amputated. he had 1 front and one back.it was sad, but he seemed to be active.  or are you talking about walking like a human on two legs? maybe for a while but then they get tired.
610475
ONE OF IT'S LEGS ARE BOTH THE SAME
316247
four-legged are usually faster than two-legged, so it's F1! ;) both are equally interesting to watch though.