The pentadactyl limb is common to humans and a lot of other mammal species, it has five digits on the hands and the feet. The structure of a human arm has a bone between its shoulder and its elbow called the humerus. Below the elbow are 2 other bones, the radius and the ulna, then there is a set of wrist bones and finally the 5-digit fingers and toes. This is an example of a pentadactyl limb and this limb can be categorised as it changes slightly between species. This similarly structured limb has changed between animals due to adaptations and evolution. This has happened in a variety of different ways for example the bat is a mammal with a pentadactyl limb that has evolved so the this limb is a wing and so the bat can then fly. The whale has evolved so that the petadactyl limb is a fin and can allow the whale to swim though the water, a cat has evlolved so that the pentadactyl limbs act as four legs and feet to walk on and allow the cat to jump and climb gracefully.
The Bat and the whale are both examples of where the pentadactyl limb has evolved so that the animals can survive in different habitats. The limb of the bat has evolved into a wing, a fully function wrist and hand attatched together by thin skin to form a wing. As the wrist is still flexible it gives the bats good manouverability when flying. This evolution has given them uniqueness that means that they are the only flying mammals. This is very beneficial for them as it reduces competition for food and for habitats, it also give them less predators than they would get as solely land mammals.
The Bat and the whale are both examples of where the pentadactyl limb has evolved so that the animals can survive in different habitats. The limb of the bat has evolved into a wing, a fully function wrist and hand attatched together by thin skin to form a wing. As the wrist is still flexible it gives the bats good manouverability when flying. This evolution has given them uniqueness that means that they are the only flying mammals. This is very beneficial for them as it reduces competition for food and for habitats, it also give them less predators than they would get as solely land mammals.
The whale on the other hand has evolved very differently, the whale has evolved to live in the water whereas the bat has evolved to fly in the sky. The whale is likely to have evolved like this because it started to look for food in the water to beat competition. Therefore spending more and more time in the water and evolving into marine mammals. The evolutionary process of the whale started with a land animal with broad flat feet that hunted for food in the water almost like a crocodile. Over time these feet became webbed and the legs became shorter allowing this mammal to move easier through the water. These limbs then evolved into flippers and the whale species evolved, these flippers then allowed the whale to navigate and propell itself through the water with ease.