How many dorsal fins does the Atlantic cod have?

The Atlantic cod has three dorsal fins.

This arrangement is a hallmark of cod-like fishes. The fins run along the back in three separate sections, while the underside has two anal fins that broadly correspond to the second and third dorsal fins. Atlantic cod also have a small chin barbel, a pale lateral line, and a broad, slightly rounded or squared tail.

Atlantic cod, Gadus morhua, are marine fish of the North Atlantic and belong to the cod family, Gadidae. They live from coastal waters to the continental shelf and may reach about 1.8 metres, although most are smaller. Their body plan is built for demersal life near the seabed, where they feed on fish, crustaceans, molluscs, and other invertebrates.

A common mix-up is confusing fins with fin rays: each dorsal fin contains many rays, but the question asks for the number of distinct dorsal-fin sections. Pacific cod and haddock also show three dorsal fins, while unrelated fish such as salmon generally have a different fin arrangement.