Analogy and Homology!!!

Analogs:

1. Flamingo   2. Great Blue Heron

1. a) Flamingos are peculiar birds that live in tropical climates. They prefer to live in wetlands because they eat fish. They typically do not migrate but due to environmental changes, some migration is becoming apparent.

http://www.seaworld.org/infobooks/flamingos/fhabitat.html

1. b) The great Blue Heron is much like the Flamingo, but these birds live all over. They too prefer wetlands. There are abundances of them in throughout the United States. They like to migrate north in the summer to breed and south to Mexico in the winters. However, they keep year round residency throughout the bulk of the United States.

http://www.allaboutbirds.org/guide/great_blue_heron/id

2. a) The analogous trait in these two birds to me is their necks and legs. Both have odd backward knees, which are actually their ankles. Both have long necks to be able to reach the water without interference of their long legs. Both of these birds live in marsh areas and eat primarily fish. This is why I believe their legs are an analog trait. They must both wade in the water for their food.

3. I do not believe that the ancestor of these odd birds had the trait. When you look at most birds, may it be water, game, finch or predator, all have an array of feet, but their legs are short.

Homologs:

1. Elk   2. Horse

1. a) An Elk is a large deer that lives in mountainous regions. They are vegetarians and herd animals. They have antlers and they shed them at the beginning of each spring.

1. b) Horses are herd animals as well. They do not require specific living conditions; they can endure both frigid winters and summers. They are vegetarians and they, like most animals (including elk), typically reproduce in the spring.

2. The homologous trait in question here is their hooves. These animals are very similar in build and attitude in a wild herd. Elk, however, have split hooves. Horses have one solid hoof. Evolution has obviously come into play here because a common ancestor of the two is a dinosaur-esque mammal that had three toes. This odd animal actually derived from a dog-sized animal called the Hyracotherium. http://chem.tufts.edu/science/evolution/HorseEvolution.htm This is a really neat site that shows the evolution of this animal, up to a horse equus, through skeletons.

Here is a picture of what scientists perceive the equine ancestor looks like. Oddly like a deer-ish horse?...