Tuna vs Grouper
Tunas and groupers are two important fish types, and they differ from each other in their external, as well as internal features. Body shapes, swimming speed, food habits, musculature, and some physiological adaptations are important to consider in differentiating these two marine fishes.
There are more than fifty species of tuna, and they belong to the Family: Scombridae. Their distribution is mainly in the tropical and the subtropical seas, but there are tuna species ranging in colder waters as well. They can swim faster than many of the fish species in the ocean, and the highest recorded speed of tuna swimming is 75 kilometres per hour. Their superfast swimming ability is a result of the streamlined body facilitated with strong longitudinal muscles, and special type of finlet movement along with the keel located between caudal fin and caudal peduncle. They in fact are one of the top five speedsters of fish. The colour of their muscles ranges between pink and dark red, which is due to the presence of myoglobin. This muscle colouration is unique to tunas. Some tuna species demonstrate higher vertebrate adaptations such as warm-blooded circulatory mechanisms, which enables them to inhabit coldwater habitats. People love to eat tuna fish as they taste good and their disease-free protein is highly valuable.
Groupers are a special type of fish of the Subfamily: Epinephelinae. All the members of this subfamily are groupers, and there are 159 species classified under 15 genera. Groupers have stout bodies with large mouths. Their large bodies could measure more than a metre and weigh around 100 kilograms. They do not swim over long distances. Groupers are predatory fishes with a special adaptation for capturing prey. They can suck their prey animal by applying a powerful force via mouth with the use of gill muscles. Groupers do not bite their prey, but they can swallow it. Interesting thing about them is that they do not chase their prey, but lie on water and wait, then suck it into the mouth and swallow. They have white coloured muscles and lack myoglobin. They live inside burrows made by them using their mouth. Usually, they make those burrows under rocks. Their reproduction is an interesting process; females are usually three to four year olds while males are always 10 – 12 year old large-bodied groupers. However, those females become large with the age and at around ten years, they undergo sexual transformation from females to males. Usually, a male have a group of females to mate with him, and sometimes the largest female becomes a male in case of an absence of a male. Groupers have higher value as a food fish for humans as well.
What is the difference between Tuna and Groupers?
• Taxonomic diversity of groupers is more than three times higher than that of tunas.
• Groupers do not form schools, whereas tunas form schools in large numbers.
• Tunas are superfast swimmers, while groupers are not.
• Groupers wait for a prey to come by and powerfully suck it into the mouth using gill muscles, whereas tunas do not suck their prey.
• The mouth is large in groupers, while tunas do not have large mouths.
• Tuna muscles are pink to dark red in colour, while grouper muscles are white.
• Tunas live in the water column more often while groupers live inside self-made burrows under rocks.