The structure and function of the different fins of the Rainbow Trout, Oncorhynchus mykiss
The Rainbow trout, belonging to the family Salmonidae, Class Actinopterygii (ray finned fish), inhabitscold streams, rivers and lakes in North America. Ones living in lakes have silver scales apart from those on their back which are dark green. They are covered in dark spots that usually go no further than the lateral line. The lateral line is a line of sense organs found on the side of the Rainbow trout. It is used to detect vibrations (and therefore movement) in the water surrounding it. A pinkish red band often runs the length of the lateral line. The shape of the Rainbow trout is a characteristic shape not uncommon from that of salmon. (Guidekenairriver.com)
Fish fins developed around 500 million years ago. A fin is a thin appendage attached to the body of an organism that causes either propulsion, stabilization, or the ability to steer and brake. The median caudal, dorsal, and anal fins are possessed by most fish species. The rainbow trout has six different types of fins- an anal fin, an adipose fin, a dorsal fin, a caudal fin, a pair of pelvic fins, and a pair of pectoral fins.
The anal fin is situated between the anus and the tail fin, on the ventral surface of the fish. In Rainbow trout, the anal fin is bordered by a black margin. This is one of the fish’s features which help to identify it. Its function is to stabilise the fish whilst it’s swimming. Due to the dorsal fins being located above the rolling axis of the Rainbow trout, the movement of the dorsal fins would cause the fish to roll whilst swimming if not for the anal fin which counteracts this movement and stabilises the fish. (Journal of experimental Biology).
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...s in the water, as well as quick change in pace and direction. This again is to evade predation.
The pectoral fins are located just behind the operculum- this is the flap of skin which covers the gill slit. Whilst swimming at a constant steady speed, the pectoral fins of the Rainbow trout are flattened against its body. However they are then held out at right angles to the body when the fish is hovering in the water, turning at slow speeds, and used to suddenly stop the fish when travelling at fast speeds. The rainbow trout is able to rotate these pectoral fins over a 30 degree range, allowing for both sculling when hovering, and braking. (Drucker EG, Lauder GV, 2003).
Evolution has taken millions of years (500 million) for the Rainbow trout to have developed the fins it has today, each with a specific purpose involved in the locomotion and stability of the fish.
Bass fishing, at present, is considered as America’s number one freshwater sport, its industry is in fact seventy percent higher in growth compared to other types of fishing activities. Bass is a fish that belongs to the Serranidae family or sea basses and the Centrarchidae or the black basses. This family of perchlike fishes are large and oblong with compressed bodies that dwell in warm and temperate seas throughout
Biology: The average length of a Skipjack Tuna is 32 inches long (80cm) and weigh anywhere between 7-22 pounds (8-10kg). The current record for the biggest Skipjack Tuna weighs in at 76 pounds (34.5kg) and was 43 inches long (108cm). The colour of the top region is either dark blue or purple, and the lower region including the belly are primarily a silver colour with anywhere from 4-6 dark, broken lines that run across the body (FLMNH). The body shape is elongated and possesses a fusiform shape, meaning it is wide in the middle and tapers at both ends; it also possesses a bilateral symmetry. There are two dorsal fins present, the first consisting of around 14-16 spines. There is a small gap in between the two fins, and the second fin is spineless (ADW) (FLMNH). Behind the second dorsal fin, are between 7-9 finlets, which aid the fish in “reducing turbulence and maintaining directional control when swimming at high speeds” (Gardieff, Susie). On the underlying side of the Tuna, the anal fin is present and it is in about the same location below the second dorsal fin, and following the anal fin is another 7-8 finlets. The fish has short pectoral fins consisting of between 26-27 rays. The fish also have a single row of teeth, shaped conically (cone shaped) (FLMNH).
The background of this article gives information that is necessary to understand the experiment. The shape of the pelvic girdle is an appropriate predictor of both phylogeny and movement in terrestrial vertebrates. However, in marine vertebrates, the gravitational forces typically applied to terrestrial pelvic girdles are not there and therefore have little impact on the shape of the girdle. Pelvic girdles of fish are generally not attached to the vertebrae and primarily are used as a place for muscles to attach and supporting of the fins. The authors discuss how in many cases the pelvic girdle could be removed and not result in any complications. However, there are some marine vertebrates that are capable of bottom walking on the ocean floor with their fins. In batoids, the pelvic fins are used for walking, which is when pelvic fins move in an alternating fashion, or punting, when both pelvic fins move at the same time. There is also augmented punting; this is when the vertebrate uses both the pectoral fins and the pelvic fins to generate more thrust, this action decreases the forces on the pelvic fins during a punt. While this locomotion would
Their shapes and patterns are similar with the majority displaying three wide stripes which are placed vertically across their bodies. The reason why these beautiful fish are known as peacock bass is because they all possess a spot on their tail fins that imitates the eye on a peacock’s feathers. The eye is used by both the peacock and the peacock fish, as a defense mechanism against predators. In addition, the eye can be used by the peacock fish as a lure of its own when
They have paired fins that lift the shark, as it is able to swim; paired pelvic fins, which stabilize the shark and letting it steer to reach its prey in a more effective manner; dorsal fins also further aide the shark in stabilization as well as the anal fin. For propelling, the shark uses the caudal fins. The caudal fins allow the shark to charge directly toward its prey.
Nick looked down into the clear, brown water, colored from the pebbly bottom, and watched the trout keeping themselves steady in the current with wavering fins. As he watched them they changed their positions by quick angles, only to hold steady in the fast water again (472).
The stories of each fish flow together as each story shows how humans have pushed to gain more control over the ocean and the delicious animals that swim in it’s depths. Greenberg starts in the free-flowing rivers where salmon are commonly found. It is there that early humans of the Northern Hemisphere most likely began their infatuation with fish. Greenberg puts it as, “It(salmon) is representative of the first wave of human exploitation..” (170) Once Europeans learned to fish, they had the ability to fish in shallow ocean water which is where sea bass are usually found. Later, fishermen s...
We have at least up to be at least 6 to 24 inches long. Instead of enjoying them selves for how big and tall they are they mke them selves taller by having extra pointy fins near there tail that make them seem taller than they actually are. They can almost every color in the world even the made up ones like Mint and Blurple. Angelfish have a black spot in the center of their foreheads that is called the fake eye but it's not just black, it is as ring with a shade of royal or dark blue.
• You need to know that fish has senses. They can hear, taste, see, and smell. They have lateral line which helps them to detect movement in water. When they are in danger, they can run away. You will really have to watch your movements because you do not want to go away with empty hands.
Two sets of skeletal elements that make up the basic fish fin are Archipterygial and Metapterygial fins. The archipterygial has both preaxis and postaxial elements. Metapterygial has only preaxial elements.
When facing a hungry hunter the ballfish rapidly swallow around 35 gulps of water in the course of 14seconds which are then pumped into stomach. Biologist at the University of Massachusetts at Amherst, Elizabeth Brainerd, has recently shown that a pufferfish’s stomach is a perfect water ballon. As water pours into it, the stomach expands up to 100 times its normal volume. Pufferfish skin is also set for ballooning. It is made of wavy fibres that straighten out as the fish inflates. When the skin expands the fish’s tail and fins immerse into skin, forming a nearly perfect sphere (balloon). When the wavy fibres finally pull tight, they become hard, giving the pufferfish a tough shell that protect from predators, giving them a hard time to penetrating. Some species have spines normally hiding in these skin fibres, but when skin is tighten spines flip up. When fish gets bigger it gives a signal to predator “don’t come closer I’m not so small as you thought”.
The reel on the left is the simpler design. That design has a stationary spindle and a bar that rotates around it to collect the line. On most models the drag works by a screw on the top of the spindle that applies pressure on the spindle to increase or decrease the friction to allow the spindle to spin if the fish applies enough force to overcome the friction. The problem with this design is that once the fish breaks the static friction the resistance to the fish pulling out line decreases and it is very difficult to change while fighting a fish.
The catfish maintains an advantage over most fish due to its ability to walk on land. This helpful adaptation comes from the pectoral spines which they flex in order to contour to their body in a walking motion. While the adaptation for land walking is impressive the ability to breathe on land is also beneficial. This ability comes from the hills of the fish which have “highly vascularized arborescent organs that act like accessory breathing structures” (Masterson 2007). Their gas bladder is also minimized to allow for stiffening so that the fish do not collapse on the land (Masterson 2007). Along with the voracious appetite of the fish they have other adaptations that make them invasive as well. The fish can survive in waters that most fish cannot such as hypoxic waters or muddy ponds. Along with being nocturnal these survival abilities allow them to invade aquaculture farms and take prey on the fish stock
Tuna are apex predators renowned for their high metabolic rates, endothermy, and physiological and biochemical adaptations that allow them to maintain intense exercise for prolonged periods of time. They continue to challenge scientists with these unique adaptations that allow them to circumvent problems trout and other teleosts face. Ironically however, while tuna will not die if they are pushed to swim at extreme speeds for long periods of time, they can perish if they are restrained and prevented from swimming because they must keep moving in order to obtain oxygen and keep blood flowing. It would seem that even tuna are not entirely immune to all of the problems and limitations of exercise in the ocean.
Verrill, A. E. "Remarkable Development of Star-Fishes on the Northwest American Coast; Hybridism; Multiplicity of Rays; Teratology; Problems in Evolution; Geographical Distribution." The American Naturalist 43.513 (1909): 542. Print.