Why do crabs walk side ways?
470994
Crabs run or move sideways because that is the way their legs bend. Crabs do not have ball-and-socket joints; many crabs have joints in their legs moving in a restricted number of planes so that they can only move sideways. Many crabs like the "Shore Crab" need to scamper sideways to avoid the legs getting tangled up with each other. \n\nMuscles work in pairs. A muscle can only retract, or pull; to lengthen again it must relax and be pulled back by another 'antagonistic' muscle. The muscle blocks in crabs are attached to the inner surface of the exoskeleton, including the ten tubular legs, including the legs with claws, or chelae, as well as other appendages.\nAslo,For animals, their body lengths are normally larger than the widths. For locomotion, animals usually move along the long axis of their bodies. As crabs run sideways, they are moving along the long axis of their bodies.
40673
Surface tension, or the attraction of water molecules sideways and inwards at the surface of the water, cause water to act like an elastic trampoline. This lets the animal float without breaking the surface.\n\nTo propel itself forward, the insect's feet must push water backward (for every action of the bug there is an equal and opposite reaction on the water). The rowing action of the legs produces miniature vortices (whirlpools) which move backward from the bug's feet.
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The basic answer is that symmetry is efficient from the point of view of growth of a multicellular creature.  The same DNA plan to construct the left side can also construct the right side.\n\nThe bigger question is why are we symmetrical from left to right, but *asymmetrical* from front to back?  (Dawkins covers this.)\n\nThe answer goes all the way back to an early stage in evolution where, basically, worms  were the dominant body plan.  \n\nThere are advantages to creating a separate opening for eating and excreting ... namely, it reduces the chance that the worm will reingest something it has just excreted.  So one end becomes the "front" end, for eating, and the other end the "rear" end for excreting.  As sense organs are far more useful for eating, they would tend to develop near the front end.  This in turn would cause nervous-system organs for processing sense information to be near the senses (the brain also goes to the front).  And all appendages that develop for locomotion, would develop to propel the organism forwards (towards the "front"), which is why tails (originally used for swimming) develop in the "rear" end, fins and legs are structured to push backwards.  And so on.\n\nHowever, while there is an advantage for front-rear asymmetry, there is no significant advantage to left-right asymmetry.  We don't find food more often on the right than on the left.  Predators don't attack more often from the right than from the left.  So it is advantageous to have sense organs arranged to look both left and right (two eyes two ears), and limbs arranged to move us both left and right (left limbs, right limbs).   So left-right symmetry has stayed.\n\nSo basically, we are bilaterally symmetrical, because almost all animals (except for things like starfish), had a common ancestor with a 'wormlike' body plan.\n.
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About 75 percent scuttle sideways, the better to keep an eye on approaching predators.\n\nAlso, Because that's the way their legs bend. Muscles work in pairs. A muscle can only retract, or pull; to lengthen again it must relax and be pulled back by another 'antagonistic' muscle.
996452
Good question.  My UNFOUNDED GUESS is that as the game started, more players (like the rest of the population) were right-handed.  If you bat right-handed, running counter-clockwise means you don't have to turn around when leaving the batter's box.  So running in that direction was just easier for most batters.\n\nThat's all I can think of...I'm curious to know the real explanation.
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If you would put a dozen crabs inside a basket, you would notice that all the crabs would try to get out.. now you would see that as one of them goes on top, the other crabs would try to pull him down in order for him to go on top>>>\n\nthe cause is self preservation ... effects ?? no unity ... if theyd try to cooperate,.. theyd be out in that basket in no time ...\n\njust see it in a human situation
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it is probably because of the winds and their directions
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They don't...their shells grow with them.  Only hermit crabs get brand new shells.  Everything else either molts or has a shell that grows with the body.
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This is a myth. Polar bears are observed using either paw, though I would suppose there are " lefties " and " righties ". They do not cover their noses when hunting, either.
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Cockroaches will die upside down with their legs curled up if they die slowly. This means natural causes, slow-acting poisons or shock.  They will die in other positions if they die very quickly - like from a very fast-acting nerve toxin or if killed by another creature.\n\nCockroaches walk and run by the coordinated action of the three sets of legs. The hind legs are dedicated to pushing. They have a limited range of movement and carry the least amount of body weight. Hind legs have large tarsal pads. The middle legs are the fulcrum of the body. They don't move much back and forth and have moderate-sized tarsal pads. The front legs are where the action is.   When they die slowly, they are propelled onto their backs.
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b/c it likes to take walks down different paths and it can't decide on one time frame, so it has many. \n\nobviously i don't know the logical answer, so i tried for a smile. did it work?
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First of all the premise of the question is not entirely correct.  Insects do not have their anus between their legs.\n\nMost animals are descended from worm-like animals.  A worm, in its simplest form is a tube with a mouth at one end, a gut and an anus at the other end.  It is more efficient to put the mouth at the front (direction of travel), so it evolved that mouth is in front, anus is in the rear.  Animals descended from that worm ancestor kept the same basic arrangement.  When animals developed legs the anus remained at the rear because the arrangement seems to work out pretty well.
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In every MLB park, except for the White Sox park (whatever it's called now) the pitcher faces in a south-west direction, they are all this direction, the exception in Chicago where the pitcher faces north-east (180 degrees from the others or "opposite") so it minimizes the 'sun factor' being in the players' (and umpires')eyes (especially the pitcher and catcher) for both during the day, and while the sun is setting at night; therefore putting his left arm "facing south", hence the south in southpaw, (obviously paw meaning hand).
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because gravity points to the center of the sphere, so no matter where you are on teh sphere, the down direction is towards the center of teh planet, wich allows penguins in teh south pole to walk on teh surface of the planet.\nIf you look at constelation however, they do appear upside down when viewed from below the equator, proving that we are walking on a sphere
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Look at how a bug does it.\nThe side opposite the direction you wish to turn takes steps slightly longer than the side toward the turn.\nFor very quick turning, the legs take strides in opposite directions.
642435
It's simply because two negatives repel. But if they are moving in different direction then too they will repel if they are close enough, but it would be hard to notice as they would already be moving away.
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It's simply a matter of tradition. In some countries, horses and carriages travelled on the right side of the road, in others, on the left. \nInterestingly enough, in the 'Down Under' countries of Australia and New Zealand, where the water goes down the drain counter-clockwise and they drive on the left side of the road, they also walk on the left side of the sidewalk, bike on the left side of the road and swim on the left side of the pool lanes. It isn't just the driving that is affected, but every mode of travel.