When given the category “amazing creations,” tuna fish might not be the first animal you think of. But a brief examination of some of this fish’s interesting characteristics might change your mind. The “chicken of the sea,” which has become one of the world’s most well-known seafoods, is also quite a remarkable member of the animal kingdom!

The name “tuna” refers to seven different species of fish, with several other related species sometimes being classified under the name. The range of characteristics in this group varies widely, but all are ocean-dwelling fish. A few of the more familiar species are the albacore, bluefin, yellowfin (or ahi), tongol and skipjack.

All tunas are generally a bluish color, with a pale underside. This coloration camouflages them from above and below. Predators hunting from above are less likely to see the dark blue color, which blends into the ocean depths, while those searching from beneath are fooled by the light-colored belly, mimicking the light filtering down from the ocean surface.

Tunas have a streamlined shape, which enables them to swim their long migratory paths through the world’s oceans with less resistance. One reason they are able to travel long distances is this efficient design, allowing them to cruise along at top speeds of over 40 miles per hour!

Tuna can range in size from fairly small to much larger than you might expect. It would probably surprise you to know that the largest tuna ever caught weighed 1,496 pounds! This particular fish was a bluefin tuna, from the largest species in the tuna family. While this is a record-setting example, it is not unusual for large tunas of some species to weigh into the hundreds of pounds.

The bluefin tuna has garnered recent public attention for more than just its size. Environmental agencies warn that its declining population may be threatened by overfishing, and unable to recover, as the demand for its bright red flesh skyrockets in seafood markets around the world. It is particularly prized as a sushi meat. Several years ago, a 444-pound bluefin tuna sold for $173,600 in a Japanese market! That’s almost $400 per pound!

One way in which tunas set themselves apart from most other fish is their ability to regulate their body temperature. Almost all fish are cold-blooded, meaning their body temperature depends solely on their environment for warmth or coolness. This is why many fish are so sensitive to temperature changes, and can survive only in a very limited range. Tunas, however, have a specialized system of blood circulation that allows them to use the energy their muscles generate to heat their body, allowing them to raise their body temperature significantly above the water surrounding them. This means they are able to migrate long distances in order to spawn or hunt, and are not confined to a small niche environment like many other fish. This remarkable characteristic means that tuna are found in almost all oceans of the world, with the exception of the frigid arctic seas.

You may have heard the term “dolphin-safe tuna.” This often refers to the albacore species, but can also include other tuna that are fished in a regulated way to insure that dolphins are not accidentally captured and killed in the process. This labeling came about because some species of tuna tend to follow dolphins as they forage the seas, wisely capitalizing on the dolphins’ superior food-finding abilities. To cut down on unnecessarily killing endangered dolphins, advocates urge the purchase of tuna that is labeled with this distinction.

Next time you sit down to enjoy a delicious lunchtime favorite, remember the many remarkable aspects of the tuna. This is only a brief overview—don’t let the learning stop here! Spur yourself to find out more about this often unappreciated member of the animal kingdom, truly a wonder of God’s great creation.