Analogy/Homology Blog Post

1.The two species that possess homologus traits I chose are sharks and sunfish, also known as Mola Mola. Both species have fins, a dorsal fin and ventral fins. The fins are the homologous trait that the species share. They also share the fact that they use gills to breath under water. The sunfish, or Mola Mola, has a large dorsal fin and vantral fin. The two fins of the sunfish are its primary use of motion. The sunfish's fins flap from side to side. The sunfish's fins are made up of thin bones. It also has a small tail that acts as a rudder. The sunfish is a large flat fish that lays on the surface of the ocean water. It is roughly six feet tall in diameter, and has a truncated body, because of its body its only way for moving around is its two fins. A Great white shark has a dorsal fin on its back, with a smaller dorsal fin on its lower back. It also has a caudal fin which is located on its tail.It also has pectoral fins on each side. Also a pelvic fin located on its under belly, along with an anal fin. The sharks fins are made up of bone and muscles that allow the shark to have power an strength when moving. The dorsal fins on the shark allow it to move forward, prompted by the caudal fin which moves from left to right that gives the shark speed. The pectoral fins enable the shark to move from left to right. And the pelvic and anal fins give the shark balance. The common ancestor of these two species where aquatic vertebrates, which evolved the aquadic body needed to maintain life in under water living. It enabled them to have fins and gills. 2. The two different species I chose where a shark and a dolphin who posses an analogous trait, which are their body types of stream lines, fins, and flippers. Both species have similar body types and move in similar motions. Although a shark is a fish and a dolphin is a mammal. A dolphin has five fins. The first is a dorsal fin that keeps the dolphin up right and allows them to not roll constantly. It's purpose is to also help maintain their body heat of 97-99 degrees since dolphins are mammals. The dorsal fin releases excess body heat if a dolphin does become over heated. The dolphins have a fluke fin in which they use it to move forward with an up and down motion. A fluke is said to be made up of two fins since it is divided by a median arch. The remaining two fins are called pectorals. These two fins allow the dolphins to stop and turn, and act to help balance the dolphin. These two fins are the only two that contain bones, while the other fins are made up of fibrous connective tissues. A Great white shark has a dorsal fin on its back, with a smaller dorsal fin on its lower back. It also has a caudal fin which is located on its tail.It also has pectoral fins on each side. Also a pelvic fin located on its under belly, along with an anal fin. The sharks fins are made up of bone and muscles that allow the shark to have power an strength when moving. The dorsal fins on the shark allow it to move forward, prompted by the caudal fin which moves from left to right that gives the shark speed. The pectoral fins enable the shark to move from left to right. And the pelvic and anal fins give the shark balance. No the common ancestor of these species did not share an analogous trait, because the common ancestor was a land mammal and the environment caused the change in the species allowing them to adapt to living in water.