Answers are grounded in this paper and cite their sources.
Theodosius Dobzhansky, Boris Spassky; GENETICS OF NATURAL POPULATIONS. XXI. CONCEALED VARIABILITY IN TWO SYMPATRIC SPECIES OF DROSOPHILA, Genetics, Volume 38, I
No takes yet. Share an insight, caveat, or question.
Dobzhansky et al. (1953) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: