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).

The Secret Life of the Brain

THE SECRET LIFE OF THE BRAIN reveals the fascinating processes involved in brain development across a lifetime. The five-part series, which will premiere nationally on PBS in winter 2002, informs viewers of exciting new information in the brain sciences, introduces the foremost researchers in the field, and utilizes dynamic visual imagery and compelling human stories to help a general audience understand otherwise difficult scientific concepts (go).

Averroes' commentary on De Anima

On the Soul (Greek Περὶ Ψυχῆς (Perì Psūchês), Latin De Anima) is a major treatise by Aristotle, outlining his philosophical views on the nature of living things. His discussion centres on the kinds of souls possessed by different kinds of living things, distinguished by the different life-processes those organisms go through. Thus plants have the capacity for nourishment and reproduction, the minimum that must be possessed by any kind of living organism. Lower animals have, in addition, the powers of sense-perception and self-motion (action). Humans have all these as well as intellect.
The notion of soul used by Aristotle is only distantly related to the usual modern conception. He holds that the soul is the form, or essence of any living thing; that it is not a distinct substance from the body that it is in; that it is the possession of soul (of a specific kind) that makes an organism an organism at all, and thus that the notion of a body without a soul, or of a soul in the wrong kind of body, is simply unintelligible. (He speculates that some parts of the soul--the intellect--may be conceived to exist without the body, but most cannot.) It is difficult to reconcile these points with the popular picture of a soul as a sort of spiritual substance "inhabiting" a body. Some commentators have suggested that Aristotle's term soul is better translated as lifeforce.

Averroes (Ibn Rushd) (1126-1198) was an Andalusian-Arab philosopher and physician. He wrote commentaries on most of the surviving works of Aristotle. These were not based on primary sources (it is not known whether he knew Greek), but rather on Arabic translations. On each work, he wrote the Jami, the Talkhis and the Tafsir which are, respectively, a simplified overview, an intermediate commentary with more critical material, and an advanced study of Aristotelian thought in a Muslim context. The terms are taken from the names of different types of commentary on the Qur'an.