Diverse African and non-African samples of the X-linked PDHA1 (pyruvate dehydrogenase E1 ␣ subunit) locus revealed a fixed DNA sequence difference between the two sample groups. The age of onset of population subdivision appears to be about 200 thousand years ago. This predates the earliest modern human fossils, suggesting the transformation to modern humans occurred in a subdivided population. The base of the PDHA1 gene tree is relatively ancient, with an estimated age of 1.86 million years, a late Pliocene time associated with early species of Homo. PDHA1 revealed very low variation among non-Africans, but in other respects the data are consistent with reports from other X-linked and autosomal haplotype data sets. Like these other genes, but in conf lict with microsatellite and mitochondrial data, PDHA1 does not show evidence of human population expansion.

Phylogenetic relationships of mangabeys within the Old World monkey tribe Papionini are inferred from analyses of nuclear DNA sequences from five unlinked loci. The following conclusions are strongly supported, based on congruence among trees derived for the five separate gene regions: (1) mangabeys are polyphyletic within the Papionini; (2) Cercocebus is the sister taxon to the genus Mandrillus; and (3) Lophocebus belongs to a clade with Papio and Theropithecus, with Papio as its most likely sister taxon. Morphologically based phylogenies positing mangabey monophyly were evaluated by mapping the sequences for each locus on these trees. The data seem to fit these trees poorly in both maximum-parsimony and likelihood analyses. Incongruence among nuclear gene trees occurred in the interrelationships among Lophocebus, Papio, and Theropithecus. Several factors that may account for this incongruence are discussed, including sampling error, random lineage sorting, and introgression.

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We suggest four ways in which human gross anatomy instructors can reinforce respect and compassion in students. First, encourage respectful language in the laboratory. The term “donor” should be used instead of “cadaver” or “corpse” in referring to the donated body because this promotes appreciation for the students' first “patient.” Second, provide the students with the actual name, age, history, and likely cause of death of the donor so that they more fully appreciate the donor as having once been a living human being. Third, prompt students to explore feelings and discuss topics stimulated by the intense experience of human dissection. Suggested topics include the students' feelings about dissecting a human being, the difficulty in deciding to donate one's body, the central importance of anatomy to a medical practitioner's role, and the historical development of the study of anatomy. Fourth, hold a memorial ceremony, in which both students and faculty participate, as a positive closure to an emotionally and intellectually intense course. Additionally, a ceremony reinforces salutary values in students, enhances social bonding among students, and encourages their appreciation of various cultural and religious beliefs. These methods introduce a new dimension of experience for anatomy students. We have developed these methods in response to what we view as a negative trend in the medical profession in which health care becomes technical and patients become objects. It is our role as faculty to reinforce respectful and compassionate attitudes in medical students from the very beginning. © 1995 WiIey‐Liss, Inc.