The Thunnini tribe of fish encompasses 15 species across five genera. Furthermore, Thunnus is the genus of fish that includes the five genera of the Thunnini tribe. That being said, Thunnini is known collectively as the tuna tribe. 

Yellowfin tuna can be found in tropical and subtropical ocean waters across the globe and are one of the fastest and strongest predators in the open ocean. This type of tuna can reach over 400 lbs and reach a length of approximately 7 ft. Bigeye tuna are highly migratory and are found in warm temperate and tropical waters around the globe. They are known to stay closer to the surface and are long-distance swimmers, usually traveling in schools. Both species have the ability to take a deep dive when needed, more than 3,000 ft.

Yellowfin tuna has a firm yet dense flesh, some regard it as beef-like. Their flesh is a deep red when raw and presents a sweet-mild ocean flavor. Bigeye tuna presents a slightly stronger flavor than yellowfin, although it is still a mild-tasting fish with a higher fat content than yellowfin tuna. The texture and color of both yellowfin tuna and bigeye tuna are quite similar, however, with bigeye the flesh may appear a vibrant reddish-pink.