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than the water around them. This ability to navigate and detect prey even in dimly
is achieved through metabolic heat and lit environments. The structure of their
specialized blood vessels called counter- eyes includes a sophisticated lens and a
current exchangers. Tuna can specifical- high density of rods and cones, enhanc-
ing their ability to perceive contrasts
Like humans they possess binocular vi- and movements in the water. Tunas keen

sion and some tuna are said to have the eyesight plays a crucial role in maintaining
their position as agile predators and helps
most acute vision of any fish. them to escape from being prey as well.

6. Why is tuna meat red in color?
ly warm parts of their bodies, like their Tuna meat appears red due to a protein
muscles, eyes, and brains which allow called myoglobin, which is responsible for
them to operate efficiently in cold water storing oxygen in muscle cells. Myoglobin
environments. Regulating their own tem- is similar to hemoglobin in blood but is
perature means tuna can live in a wide found in muscle tissue. Tuna, being a high-
range of conditions, and can be found in ly migratory, fast-swimming and warm
arctic and tropical waters. The extra heat blooded fish, have a high concentration

in their muscles gives them a boost in of myoglobin in their muscles to support
power and speed. It also helps them dive their endurance and oxygen needs. The
deep, reaching depths of 500 to 1,000
meters to search for food and to avoid These magnificent fish traverse vast

predators. expanses of ocean between breeding

5. Tuna have some of the best eye- and feeding grounds.

sight of all fishes
Tuna possess remarkable eyesight that myoglobin in tuna muscles binds oxygen
aids them in their swift and efficient efficiently, giving the meat a deep red or
hunting abilities. Like humans they pos- pink color. This characteristic coloration
sess binocular vision and some tuna are is prized by chefs and consumers alike, as
said to have the most acute vision of any it indicates freshness and quality in tuna
fish. Their eyes are large and well-adapt- meat. As tuna ages or is exposed to air,
ed to low-light conditions, allowing them myoglobin can oxidize, causing the meat

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