Every other creature in God’s Green Earth moves forwards and backwards - even Robert De Niro (silly reference to “Mean Streets” where he tried to move like a crab).
So, why do crabs move sideways? Every time I see them flittering about, it always creeps me out!
Because their legs stick out sideways. Put your hand on a table and crook your fingers to pull your hand along. Now try to move your hand laterally by moving your fingers laterally. Pulling is much easier. Crabs move by, essentially, ‘crooking their fingers’.
Sidewinder snakes?
There is no denying that you are keerect on that one!