Which order has hind femora greatly enlarged for jumping and tympana on the sides of the first abdominal segment?

Which order has hind femora greatly enlarged for jumping and tympana on the sides of the first abdominal segment?

• A. Tetrigrade
• B. Acrididae
• C. Pleoptera
• D. Gryllacrididae

Answer: (B)

The main idea is that two features together identify these grasshoppers: a hind leg built for powerful jumps and auditory organs located on the first abdominal segment. The hind femora are greatly enlarged in grasshoppers to store and release energy for leaps, giving them their strong saltatorial (jumping) ability. At the same time, the tympana (hearing organs) are positioned on the sides of the first abdominal segment in Caelifera, the group that includes grasshoppers. This combination—big hind femora for jumping plus abdominal tympana—points to Acrididae, the grasshoppers. Other groups either don’t have such pronounced jumping legs or place tympana in different locations, so they don’t match both traits as neatly.

The main idea is that two features together identify these grasshoppers: a hind leg built for powerful jumps and auditory organs located on the first abdominal segment. The hind femora are greatly enlarged in grasshoppers to store and release energy for leaps, giving them their strong saltatorial (jumping) ability. At the same time, the tympana (hearing organs) are positioned on the sides of the first abdominal segment in Caelifera, the group that includes grasshoppers. This combination—big hind femora for jumping plus abdominal tympana—points to Acrididae, the grasshoppers. Other groups either don’t have such pronounced jumping legs or place tympana in different locations, so they don’t match both traits as neatly.