We present reciprocal transformations for the spectral problems of Korteveg de Vries (KdV) and modified (mKdV) equations. The resulting equations, RKdV (reciprocal KdV) RmKdV mKdV), are connected through a transformation that combines both Miura transformations. Lax pairs straightforwardly obtained by means aforementioned have also identified classical Lie symmetries RmKdV. Non-trivial similari...

Why do males in some species contribute to offspring care, while in others males have very little involvement with females and their offspring, beyond conception? This paper addresses this question using a combination of theoretical biology, genetic computation, game theory and data from living primates. Because of the heavy energetic demands of gestation, lactation and offspring care, studies ...