Why do catfish have an odd number of whiskers?

Catfish typically have an odd number of whiskers, or barbels, primarily for sensory purposes. These whiskers help them navigate their environment, locate food, and sense changes in water currents. The odd number may enhance their ability to detect stimuli from different directions, allowing for better spatial awareness in murky waters where visibility is low. Additionally, having an odd number of whiskers can reduce the likelihood of them becoming tangled or damaged.