Edited by Wenda Trevathan, New Mexico State University, Mesilla, NM, and accepted by Editorial Board Member C. O. Lovejoy February 23, 2021 (received for review October 23, 2020)The relatively small human birth canal has arisen from an evolutionary trade-off between multiple antagonistic selective forces. We present evidence that a large pelvic floor is disadvantageous for maintaining continence and supporting the weight of the inner organs and the fetus through multiple finite element analyses of pelvic floor models varying in size and thickness. An increase in pelvic floor size led to a...…Edited by Wenda Trevathan, New Mexico State University, Mesilla, NM, and accepted by Editorial Board Member C. O. Lovejoy February 23, 2021 (received for review October 23, 2020)The relatively small human birth canal has arisen from an evolutionary trade-off between multiple antagonistic selective forces. We present evidence that a large pelvic floor is disadvantageous for maintaining continence and supporting the weight of the inner organs and the fetus through multiple finite element analyses of pelvic floor models varying in size and thickness. An increase in pelvic floor size led to a...WW…