Maternal investment, sex-differential prospects, and the sex ratio in wild house mice |
| |
Authors: | Sven Krackow |
| |
Institution: | Fakult?t für Biologie, Universit?t Konstanz, D-78434 Konstanz, Germany, and Forschungsbereich Populationsbiologie und Züchtungsforschung, Forschungsinstitut für die Biologie landwirtschaftlicher Nutztiere, D-18196 Dummerstorf, Germany, DE
|
| |
Abstract: | In a population of first-generation offspring from wild-caught house mice (Mus musculus domesticus), previous evidence suggested that male fitness is more strongly affected by an increase in body weight than female fitness.
This paper shows that in these mice the young are weaned at heavier weights the smaller the litter and the better the maternal
body condition. These effects persisted into adulthood and were less pronounced in female young. However, contrary to expectation
from conventional sex ratio theory, maternal condition and litter size had no detectable effect on sex ratios. Also, litter
size did not affect sex ratios in two populations of laboratory-kept, wild-caught western (M. m. domesticus) and eastern house mice (M. m. musculus). Wild house mice, therefore, appear not to adaptively manipulate the sex ratio of offspring. It is argued that this absence
of sex ratio trends might not be maladaptive, but rather that models currently used to predict sex ratio trends in rodents
may not be valid.
Received: 13 March 1997 / Accepted after revision: 9 August 1997 |
| |
Keywords: | Trivers-Willard hypothesis Mus musculus Sex ratio Maternal investment |
本文献已被 SpringerLink 等数据库收录! |
|