What animal has the largest penis compared to its size?

The barnacle is the creature with the largest penis as a proportion of its body size. Among vertebrates, the Argentine blue-bill duck has the longest penis in relation to its body size.

1. Which animal has the largest penis per size?

Which animal has the largest penis per size?

Barnacles have the biggest penis-to-body size ratio, with genitalia nearly eight-times their total body length. Barnacles are stuck in place for life, so they use their super-long penises to reach other nearby crustaceans, blindly depositing sperm inside their neighbors.