由于个体种化石的的数量统计随着时间的推移而变化,研究生物灭绝的古生物学家们更倾向于对称为类的有相互联系的整个物种种群进行统计研究。
Rather than counting individual species of fossils,which vary over time, palaeontologists who study extinction usually countentire groups of related species, called genera.
当时的人数甚至不及现在濒临灭绝的黑猩猩(21000头)和大猩猩(25000头)的有效种群大小(即能生育的个体数量)。
That number is smaller than current figures for the effective population size (or number of breeding individuals) for endangered species such as chimpanzees (21, 000) and gorillas (25, 000).
个体被发现的时间、地点已经建立模式用于预测种群生存和数量规模。
Patterns of when and where individual animals have been observed are used to estimate survival and population size.
只考虑这些不确定的繁殖能力,灭绝不太可能如果个体的数字在一个种群数量超过50并且种群数量在增长。
Taking only this uncertainty of ability to reproduce into account, extinction is unlikely if the number of individuals in a population is above about 50 and the population is growing.
应用优化算法高度并行、种群个体收敛高度一致的特性,较好的解决了高维统计计算中样本数量与计算时间、样本数量与样本质量之间难以协调的问题。
The problems of harmony between sample number and calculation time, as well as between sample number and sample quality in higher order statistics calculation were achieved.
沟谷热带雨林群落结构和功能(光合生产)的稳定性是以多个物种种群以及各层次中个体数量的相对稳定来维持的。
The stability of structure and function (photosynthesis production) of the ravine tropical rain forest is maintained by a lot of tree populations, and relative constancy of individuals in each layer.
沟谷热带雨林群落结构和功能(光合生产)的稳定性是以多个物种种群以及各层次中个体数量的相对稳定来维持的。
The stability of structure and function (photosynthesis production) of the ravine tropical rain forest is maintained by a lot of tree populations, and relative constancy of individuals in each layer.
应用推荐