The “triangular” pattern of reproduction in arvicoline rodents predicts small fecundity early and late in life and high fecundity in the middle. In producing this pattern, the effects of maternal age and parity are typically highly confounded. We present results of a laboratory study designed to disentangle these effects in the common vole (Microtus arvalis) by analyzing variation in sizes of the first 2 litters born to 3 age classes of females subjected to photoperiods of 8 h and 16 h of light. Although the youngest females, paired at 2 weeks of age, decreased size of the 2nd litter in either light environment, the older 2 classes, paired at 3–4 months and 1 year of age, increased their 2nd litters, as predicted by the triangular pattern. This age-specific effect of parity could be explained by differences in the size of 1st litters.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.