Cousin Marvin
If you were looking for the article about the fish, then see Marvin.
If you were looking for the article about animal control officer, then see Marvin (animal control officer).
Character
Marvin[1] is one of Plankton's cousins. Unlike Sheldon's other cousins, it is unknown if he is a Plankton or if he is one of Sheldon's maternal cousins. He appears in the short, "Plankton. A Thank You Would Be Nice."
Description
Marvin appears to be a much more primitive species of plankton. Marvin is notably smaller than some of Sheldon's other cousins.[1]
History
Cousin Marvin appears in the short, "Plankton. A Thank You Would Be Nice." when Plankton is explaining how plankton are the most important living creatures on the planet. He uses cousin Marvin, who he describes as stupid, as an example, but he then explains how Marvin has planktonic plant brains that make up half of the Earth's oxygen.