New perspectives on evolutionary medicine: the relevance of microevolution for human health and disease

Evolutionary medicine (EM) is a growing field focusing on the evolutionary basis of human diseases and their changes through time. To date, the majority of EM studies have used pure theories of hominin macroevolution to explain the present-day state of human health. Here, we propose a different approach by addressing more empirical and health-oriented research concerning past, current and future microevolutionary changes of human structure, functions and pathologies. Studying generation-to-generation changes of human morphology that occurred in historical times, and still occur in present-day populations under the forces of evolution, helps to explain medical conditions and warns clinicians that their current practices may influence future humans. Also, analyzing historic tissue specimens such as mummies is crucial in order to address the molecular evolution of pathogens, of the human genome, and their coadaptations.Frank Jakobus Rühli and Maciej Henneber

The fighting hypothesis in combat:how well does the fighting hypothesis explain human left-handed minorities?

The strong population bias in hand preference in favor of right-handedness seems to be a typical human trait. An elegant evolutionary hypothesis explaining this trait is the so-called fighting hypothesis that postulates that left-handedness is under frequency-dependent selection. The fighting hypothesis assumes that left-handers, being in the minority because of health issues, are still maintained in the population since they would have a greater chance of winning in fights than right-handers due to a surprise effect. This review critically evaluates the assumptions and evidence for this hypothesis and concludes that some evidence, although consistent with the fighting hypothesis, does not directly support it and may also be interpreted differently. Other supportive data are ambiguous or open for both statistical and theoretical criticism.We conclude that, presently, evidence for the fighting hypothesis is not particularly strong, but that there is little evidence to reject it either. The hypothesis thus remains an intuitively plausible explanation for the persistent left-hand preference in the population. We suggest alternative explanations and several ways forward for obtaining more crucial data for testing this frequently cited hypothesis.

Taiwan Aboriginals and Peoples of the Pacific-Asia Region: Multivariate Craniometric Comparisons.

RefereedStepwise discriminant function analysis and Mahalanobis’s generalized distance are applied to twenty-nine cranial measurements recorded in 2,531 male crania representing five Taiwan aboriginal cranial series and fifty prehistoric, modern, and near modern human groups. The Taiwan aboriginal cranial series include modern samples of Atayal, Bunun, Pazeh, Babuza, and archaeological human remains from the Shi San Hang site (ca 1800-500 BP). The comparative cranial series represent East Asia, Southeast Asia, Australia, New Guinea, island Melanesia, Polynesia, and Micronesia. The results of two separate analyses, one using five and the other using fifty-five groups, are presented. A relatively close connection between the Babuza, Pazeh, and Shi San Hang aboriginal cranial series is observed while the Atayal and Bunun series remain relatively well differentiated. Connections between Taiwan aboriginal groups and cranial series from Polynesia suggest that Taiwan’s aboriginal inhabitants may have been the ancestral source of these inhabitants of Remote Oceania. Similarly, these results suggest that the ultimate source of Taiwan’s prehistoric and modern aboriginal groups may be among the early inhabitants of eastern (Northeast or Southeast) Asia. The results of the present craniometric analysis are compared with other lines of evidence which have been used to examine the affinities and origins of Taiwan’s aboriginal peoples