Why Do Some Crustaceans Want to Be Crabs? The Fascinating Phenomenon of Carcinization

🦀Crustaceans have evolved the crab shape multiple times through the process of carcinization.

🌊The crab shape enables greater mobility, allowing crabs to walk, run, swim, and burrow in different habitats.

🦞True crabs originated during the Cretaceous Period and their diversity increased during this time.

🦐There has been a long-term shift toward more crab-shaped species and a decline in long-bodied crustaceans.

🔄Some crustaceans have decarcinized, losing the crab-like shape and returning to a lobster-like form.

What is carcinization?

—Carcinization is the process by which crustaceans, such as lobsters and shrimps, evolve to resemble crabs in shape.

Why do crustaceans evolve to look like crabs?

—The crab shape offers greater mobility, allowing crustaceans to walk, run, swim, and burrow more efficiently. It also helps them evade predators.

When did true crabs originate?

—True crabs originated during the Cretaceous Period, approximately 95 to 90 million years ago.

Why is there a decline in long-bodied crustaceans?

—There has been a long-term shift toward more crab-shaped species, specifically true crabs. This shift may be due to the advantages of the crab shape in terms of mobility and survival.

What is decarcinization?

—Decarcinization is the process by which crustaceans lose the crab-like shape and return to a lobster-like form.

00:00Crustaceans have evolved to resemble crabs in shape through a process called carcinization.

03:41The crab shape offers greater flexibility and mobility, allowing crabs to walk, run, swim, and burrow in various habitats.

06:15True crabs originated during the Cretaceous Period and their diversity increased during this time.

06:23There has been a shift toward more crab-shaped species and a decline in long-bodied crustaceans.

05:59Some crustaceans have decarcinized, losing the crab-like shape and returning to a lobster-like form.