Friday, 24 August 2007

Hall of Human Origins

All species consist of individuals that differ at some level. In Homo sapiens, population diversity arose as small groups occupied varied environments around the world. Localized populations changed due to genetic drift and natural selection. For example, some populations eventually showed more susceptibility to certain diseases, or more ability to digest certain foods. Superficial differences in stature and hair, eye, and skin color also arose among individuals and populations.Although these population changes take place at a genetic level, it does not mean that genes define "race." Race is cultural and social, not biological.Small, isolated groups are less and less prevalent in the human population. Our population is now abundant, consisting of larger, varied groups that intermingle and overlap. Since humans reproduce both within and between groups, we constantly mix genetic information. As a result, genetic differences between people of the same "racial" group can be greater than the those between people of two different groups. Furthermore, influences other than genes—such as hormones and environmental factors—also contribute to individual variation (go).

No comments:

Contents of the day

Article of the Day

Celiac Disease

Celiac disease is a digestive disorder in which gluten—a protein found in wheat and other flours—generates an inflammatory response in the small intestine, damaging tissue and impairing nutrient absorption. A lifelong gluten-free diet is the only effective way to relieve symptoms, which include diarrhea, weight loss, and depression. Though it was observed as early as 200 CE, celiac disease's link to wheat remained undiscovered until 1950. What natural event may have contributed to the discovery? More... Discuss

This Day in History

Grand National Assembly of Turkey Is Founded (1920)

The treaty negotiated between the Allies and the Ottoman Empire at the end of WWI liquidated the Ottoman Empire and virtually abolished Turkish sovereignty, but nationalists under the leadership of Mustafa Kemal Atatürk were committed to establishing a sovereign Turkish state. During the struggle for independence, Atatürk pushed for the creation of a national assembly, which declared itself the supreme governing power when convened in 1920. When did it formally declare the sovereignty of Turkey? More... Discuss

Today's Birthday

Max Planck (1858)

Planck was an influential German physicist whose work on black body radiation earned him the Nobel Prize in Physics in 1918. He also discovered the elementary quantum of action, now known as Planck's constant. As the influential president of the Kaiser Wilhelm Society, he denounced Hitler's persecution of Jewish scientists and resigned in protest in 1937. Tragically, four of Planck's five children died before he did. One of his sons was executed after being implicated in what plot? More... Discuss

In the News

repletion discuss

Definition:(noun) The state of being satisfactorily full and unable to take on more.
Synonyms:satiation, satiety
Usage:Then Tarzan and Sheeta feasted to repletion.

Quote of the Day
My father must have had some elementary education, for he could read and write and keep accounts inaccurately.
George Bernard Shaw
(1856-1950)
Discuss