哺乳动物母体繁殖对策的研究

哺乳动物以雌体哺乳和雄性有限的 贡献共同哺育。雌体是整个繁殖过程的中心事件，也是最耗能量的过程。哺乳动物哺乳的行为表现可影响母体民仔未来的繁殖。哺乳期越长对后代越有利，但另一方面，母体的繁殖代价可影响其存活和繁殖力；后代质量与胎仔数间存在着权衡，作为胎仔数的函数，后代质量以种群新生个体补充概率潜在地影响亲本的适合度；与出生时不明确的格局相比较，育幼结束时的权衡通常非常明显；后代体重与生长速率的差异可影响新生个体的补充数；如果幼仔体重差异保持到成体，这些差异将超越简单的后代补充数而持续影响母体的广义适合度。雌性成体体重与胎仔数之间存在明显的相关性。

STUDIES on the STRATEGIES of MATEEERNAL PRODUCTION in MAMMALS

In many mammals,milk production by females and limited contributions of males rear offspring,and lactation is clearly the most unique event of the purcess of the production and the most energetically expensive.Mammals lactation performance may influence future reproduction of a mother and her young.As a consequence,a long lactation period be profitable for the offspring.For the mother,on the other hand,the cost of reproduction may influence her survival and her fecundity.There being a trade-off between litter size and quality of offspring,quality of offspring,as a function of litter size,potentially affects parental fitness through the probability of recruitment and also throng differevntial reproduction by offspring.In contrast to equivocal patterns at birth ,tradeoffs usuallg are readily apparent to ward the end of parental care;Differences in body size and growth rates of offspring can influence the probability of the recruitment.If differences in size among young are maintained into adulthood,they will continue to affect a mother's inclusive fitnees beyond simple recruitment of her offspring.The body size of female's adulthood significantly correlates with her litter size.