The integument of species has changed a great deal over the course of evolutionary history. The flying fish integument is composed of an outer epidermal layer, …show more content…
The tail fin of the flying fish is a laterally flattened, hypocercal tail. A hypocercal tail is asymmetrical, with a larger portion of the fin on the bottom and a small portion of the fin on the top. In the water the flying fish undulate the fin to create thrust. However, the flying fish is also able to glide through the air. To glide, they pick up speed while swimming through the water and use that force to exit the water. Once out of the water, the large bottom portion of their hypocercal tail is still in the water. The gliding motion is able to be continued by the tip of the tail being undulated in the water, creating thrust. The flying fish uses its pectoral and pelvic fins to create a gliding surface. In contrast, the jerboa lives in a terrestrial environment. The jerboa is bipedal, and moves using solely the back legs; the forelimbs are used for collecting food and digging. The jerboa uses jumping as its locomotion style. The hind limbs have a short forelimb and a long hind limb. The jerboa’s hind leg design results in a large gear ratio, and therefore is designed for …show more content…
Deoxygenated blood is pumped out of the heart to the gills. The blood is oxygenated at the gills and sent throughout the body before returning to the heart deoxygenated. The flying fishes have six aortic arches that are responsible for bringing blood to and from the gills. In tetrapods, arches I, II, and V, are lost. Arch III becomes the carotid, arch IV, becomes the aorta, and arch VI becomes the pulmonary trunk. In mammals, such as the jerboa, the left side of the aortic arch is retained. The jerboa has a four chamber heart that runs on a double circuit system. The oxygenated blood comes into the right atrium of the heart, and then into the right ventricle. The blood is them pumped to the lungs to be oxygenated. After oxygenation the blood is taken to the left atrium, then the left ventricle. From the left ventricle the oxygenated blood is pumped out the aorta to the rest of the