Which group typically has four pairs of legs?

Which group typically has four pairs of legs?

• A. Insects
• B. Arachnids
• C. Crustaceans
• D. Myriapods

Answer: (B)

Eight legs in total is typical of arachnids, since they commonly have four pairs of legs attached to the front body segment. This distinguishes them from insects, which have three pairs of legs, and from myriapods, which have many more legs (centipedes with one pair per body segment and millipedes with two). Crustaceans vary a lot too, with many having five pairs of walking legs (and other appendages), rather than four pairs. So the group that most often shows four pairs of legs is arachnids. Spiders and scorpions are classic examples.

Eight legs in total is typical of arachnids, since they commonly have four pairs of legs attached to the front body segment. This distinguishes them from insects, which have three pairs of legs, and from myriapods, which have many more legs (centipedes with one pair per body segment and millipedes with two). Crustaceans vary a lot too, with many having five pairs of walking legs (and other appendages), rather than four pairs. So the group that most often shows four pairs of legs is arachnids. Spiders and scorpions are classic examples.