THE GENETIC STRUCTURE OF NATURAL POPULATIONS OF PAST AND PRESENT

分子遗传变异模式和动态的监测 自由放养的种群揭示了许多关于 影响种群和物种的生存。运用分子生物学的方法 遗传学(等位基因、双向电泳、限制性片段 核和线粒体DNA的长度多态以及聚合酶 链式反应)来监控序列变异)，我们发现 影响自然种群稳定性的几个因素。 历史上的近亲交配在濒危种群中被推断出来 猎豹、狮子、佛罗里达豹和黑脚雪貂。这个 这些近亲交配事件的后果包括近亲交配抑郁 反映在先天缺陷和生理损害上 繁殖。此外，由于近亲交配减少了遗传多样性，这些 事件增加了人口对 传染病媒介，偶尔进化机制以 消除免疫差异。最后，有效地应用 分子钟假说解决了发散计时和 猩猩、大熊猫等物种的系统发育位置 食肉动物和灵长类动物的物种。

The monitor of the pattern and dynamics of molecular genetic variation in free-ranging populations has revealed much about the factors that influence population nd species survival. Using the methods of molecular genetics (allozyme, two dimensional electrophoresis, restriction fragment length polymorphism of nuclear and mitochondrial DNA, and polymerase chain reaction) to monitor sequence variation), we have discovered several components that influence stability of natural populations. Historic inbreeding has been deduced in endangered populations of cheetahs, lions, Florida panthers and black-footed ferrets. The consequences of these inbreeding events included inbreeding depression as reflected in congenital defects and physiological impairment to reproduction. Further, as inbreeding reduces genetic diversity, these events increase susceptibility and vulnerability of populations to infectious disease vectors that occasionally evolve mechanisms to abrogate immune differences. Finally, efficacious application of the molecular clock hypothesis has resolved divergence timing and phylogenetic placement of species of orangutan, giant panda, and other species of carnivores and primates.