Ricklefs R E, Scheuerlein A, Cohen A
Department of Biology, University of Missouri-St Louis, 8001 Natural Bridge Road, St Louis, MO 63121-4499, USA.
Exp Gerontol. 2003 Jul;38(7):741-5. doi: 10.1016/s0531-5565(03)00101-3.
We have analyzed birth records from the International Species Inventory System database of zoo animals to describe patterns of fertility as a function of age in birds and mammals. Unlike age at death, fertility in captive populations is partly controlled by animal keepers depending on availability of space and potential mates and on the aims of captive propagation programs. Thus, fertility records must be considered carefully to avoid potential age-specific biases. The zoo data suggest that fertility declines from a peak at young adult ages in most species. The rate of decline in reproductive function is correlated with the rate of somatic aging, indicated by the increase in mortality rate with age, and with the age at peak fertility. Over the sample as a whole, these patterns do not differ systematically between the sexes, nor do they differ between birds and mammals. While it is clear that the demographic consequences of aging of the reproductive system follow a different course than the aging of somatic tissue, the rates of each are correlated either through functional connections or through parallel evolutionary responses to common selective factors.
我们分析了国际物种普查系统数据库中动物园动物的出生记录，以描述鸟类和哺乳动物的生育模式随年龄的变化情况。与死亡年龄不同，圈养种群的生育能力部分由动物饲养员根据空间和潜在配偶的可用性以及圈养繁殖计划的目标来控制。因此，必须仔细考虑生育记录，以避免潜在的年龄特异性偏差。动物园数据表明，大多数物种的生育能力从年轻成年期的峰值开始下降。生殖功能的下降速度与体细胞衰老速度相关，体细胞衰老速度通过死亡率随年龄的增加来表示，也与生育高峰期的年龄相关。在整个样本中，这些模式在性别之间没有系统性差异，在鸟类和哺乳动物之间也没有差异。虽然生殖系统衰老的人口统计学后果显然与体细胞组织衰老的过程不同，但两者的速率要么通过功能联系，要么通过对共同选择因素的平行进化反应而相关。
