The Concept of Natural Selection in Theodosius Dobzhansky: Its Development and Interpretation (original) (raw)

The Concept of Natural Selection in Theodosius Dobzhansky: Its Development and Interpretation

2021, Evolutionary Biology - New Perspectives on its Development, Vol. 3, Richard G. Delisle (Ed): Natural Selection. Springer Verlag, Chapter 11

Throughout his career, Dobzhansky (1900-1975) doubted whether natural selection could explain evolution. My first thesis is that his doubt was qualified and declined during his life, but never disappeared. I offer five reasons for his hesitation. First, evolution was possible without natural selection. He included drift, cooperation, and polyploidy with natural selection as causes of evolution. During his career, he gained confidence in natural selection but kept an open mind about other causes of evolution. Second, the selective neutrality of alleles required for drift was not established, and this affected the assessment of selection. Third, Dobzhansky wanted a causal account of evolution. But initially no causal connection between short-term natural selection and adaptation and long-term speciation could be established by experiment. Later, empirical support for a role of natural selection in evolution became available, but was insufficient. Fourth, it was unlikely that the timing of reproductive isolation would make adaptive evolution possible. Fifth, the selection-balance controversy exposed a variety of additional reasons for doubts about the role of selection. This skepticism about the role of selection in evolution makes Dobzhansky an unlikely participant in the so-called hardening of the synthetic theory of evolution. My second thesis is that Dobzhansky interpreted natural selection as natural evil and that this interpretation can be explained in the context of his religion. 1✉ 1 e.Proofing | Springer