Theodosius Dobzhansky and the genetic race concept

The use of ‘race’ as a proxy for population structure in the genetic mapping of complex traits has provoked controversy about its legitimacy as a category for biomedical research, given its social and political connotations. The controversy has reignited debates among scientists and philosophers of science about whether there is a legitimate biological concept of race. This paper examines the genetic race concept as it developed historically in the work of Theodosius Dobzhansky from the 1930s to 1950s. Dobzhansky’s definitions of race changed over this time from races as ‘arrays of forms’ or ‘clusters’ in 1933–1939, to races as genetically distinct geographical populations in 1940–1946, to races as genetically distinct ‘Mendelian populations’ in 1947–1955. Dobzhansky responded to nominalist challenges by appealing to the biological reality of race as a process. This response came into tension with the object ontology of race that was implied by Dobzhansky’s increasingly holistic treatment of Mendelian populations, a tension, the paper argues, he failed to appreciate or resolve.     

Adaptive management for eradication of exotic species

The problems of controlling exotic species have been acknowledged as serious threats to an indigenous ecosystem as well as to society. In response to these threats, various management programs of exotic species have been proposed for supporting eradication in many regions. Although eradication is regarded as the first-best solution, such attempts have been unsuccessful in reality due to mainly two factors: (1) stock-dependent catchability, and (2) uncertainties. This article demonstrates when to aim at eradication through addressing an optimal adaptive management strategy in the framework of a bio-economic model with the aforementioned factors. The study sets out that the sensitivity of catchability in response to a change in the existing stock determines whether or not aiming at eradication is justified. The results also show that process uncertainty associated with stock growth significantly affects the timing of removal actions for eradication, and an increase in the degree of uncertainty could help achieve eradication in a cost–effective manner if we optimally adapt our removal actions to the uncertainty.