Analogy and Homology

Homologous Trait

The Crocodile
Crocodiles are the more biologically complex reptiles despite their prehistoric look.Their diet consists mainly of small mammals, birds, fish, crabs, insects, snails, frogs, and occasionally carrion. A crocodile has a long, pointed snout. Some of its lower teeth are exposed when the jaw is closed. It is olive-green with dark cross bands on the back and tail. The skin is protected by large bony plates. The crocodile has a heavy tail, short legs, and webbed hind feet. They  use their tails mainly to guide them through the water while paddling along with their webbed feet.

The Whale 

Whales have sleek, virtually hairless bodies that taper from head to tail. They are different shades of black or grey.Whales balances itself and steers with its flippers, or forelimbs.The flipper bones are similar to those of the foreleg and hand (or forefoot) of land mammals, but have been modified for water living. Their diet consists of krill, plankton and small fish.

Homologus Trait

The common homologus trait that is shared between the whale and crocodile is the whales fins and the crocodiles webbed feet. The differences in there structure is the crocodiles webbed feet has a longer humerus then the whales fin and also the whale has longer phalanges then the crocodile .The whale uses its fin to swim and keep balance. The crocodile uses its webbed feet to swim also but it also uses it to walk on land. These homologus traits exhibit differences between the whale and crocodile because one can use its traits for both water and land and the other can only use it for water.

Common Ancestor

A common ancestor would have to be a mammal. It would have to be a mammal because, every mammal has either fins or webbed feet.

Analogous Trait

The Hawk

Hawks have a wingspan of over four feet, with broad, and rounded wings. Its diet is mainly small mammals, but it also includes birds and reptiles. Prey varies with regional and seasonal availability, but usually centers on rodents. They are usually brown or golden. 

The Moth

Moths are insect closely related to butterflies. Moths tend to have thick hairy bodies and more earth tone colored wings. Butterflies and moths have a highly developed sense of smell. The legs are long and slender and can be used only for crawling and their two wings the fore wings and the hind wings, consist of membranous tissue supported by a network of tiny hollow tubes called veins.  Moths eat  nectar, aphid juice, and water.

Analogous Traits

The common analogous trait that a hawk and a moth share is their wings. The hawk and moth use there there wings to fly. The difference is function is of coarse the hawks bone structure is longer but it has less bones in its wings then a moth does. The moth has two set of wings and also has a more complex bone structure then a hawk does.

Common Ancestor

A common ancestor that a hawk and a moth can have is a mammal or an insect. I would say more of a mammal because moths do have very similar functions as a hawk which is a mammal. Also the patterns in both hawk and moths wings are very similar I think that happened because of there adaptation. Just like the evolution of the pepper moths and how over time they adapted to their habitat I think hawks also adapt to their environment and start to have traits that will help in its habitat just like its color and patterns on its feathers.