Since the 80 s, our country is working on implementing birth limitation and having only one, ＂one of the most glorious＂ policy, the policy is very good solve the problem of China＇s population rising too rapidly, at...Since the 80 s, our country is working on implementing birth limitation and having only one, ＂one of the most glorious＂ policy, the policy is very good solve the problem of China＇s population rising too rapidly, at the same time also the certain negative impact. In other words, lose the sole group production is to limit the second child victims. Of course, only child＇s death is the biggest hidden trouble, this not only can bring economic loss to lose alone group, will give group cause huge loss alone cannot make up for the spiritual loss. If only children died, their relatives and friends, especially the parents very easily into the depression, are not interested in anything, their thoughts are on the verge of collapse, it is also a need to study and to explore the topic.展开更多
Translocations, especially assisted colonizations, of animals are increasingly used as a conservation management tool. In many cases, however, limited funding and other logistic challenges limit the number of individu...Translocations, especially assisted colonizations, of animals are increasingly used as a conservation management tool. In many cases, however, limited funding and other logistic challenges limit the number of individuals available for transloeation. In conservation genetics, small populations are predicted to rapidly lose genetic diversity which can deteriorate population survival. Thus, how worried should we be about the loss of genetic diversity when introducing small, isolated populations？ Historical species introductions provide a means to assess these issues. Here we review 13 studies of ＂assisted colonization-like＂ introductions of animals, where only a small known number of founders established an isolated population without secondary contact to the source population. We test which factors could be important in retaining genetic diversity in these cases. In many cases, loss in heterozygosity （-12.1%） was detected, and more seriously the loss in allelic richness （-27.8 %）. Number of founders seemed to have an effect but it also indicated that high population growth rate could help to retain genetic diversity, i.e. future management actions could be effective even with a limited number of founders if population growth would be enhanced. On the contrary, translocated organisms with longer generation times did not seem to retain more genetic diversity. We advocate that, where possible, future studies on translocated animals should report the loss of genetic diversity （both heterozygosity and allelic richness）, which is essential for meta-analyses like this one for deepening our understanding of the genetic consequences of assisted colonization, and justifying management decisions [Current Zoology 61 （5）： 827-834, 2015].展开更多
文摘Since the 80 s, our country is working on implementing birth limitation and having only one, ＂one of the most glorious＂ policy, the policy is very good solve the problem of China＇s population rising too rapidly, at the same time also the certain negative impact. In other words, lose the sole group production is to limit the second child victims. Of course, only child＇s death is the biggest hidden trouble, this not only can bring economic loss to lose alone group, will give group cause huge loss alone cannot make up for the spiritual loss. If only children died, their relatives and friends, especially the parents very easily into the depression, are not interested in anything, their thoughts are on the verge of collapse, it is also a need to study and to explore the topic.
文摘Translocations, especially assisted colonizations, of animals are increasingly used as a conservation management tool. In many cases, however, limited funding and other logistic challenges limit the number of individuals available for transloeation. In conservation genetics, small populations are predicted to rapidly lose genetic diversity which can deteriorate population survival. Thus, how worried should we be about the loss of genetic diversity when introducing small, isolated populations？ Historical species introductions provide a means to assess these issues. Here we review 13 studies of ＂assisted colonization-like＂ introductions of animals, where only a small known number of founders established an isolated population without secondary contact to the source population. We test which factors could be important in retaining genetic diversity in these cases. In many cases, loss in heterozygosity （-12.1%） was detected, and more seriously the loss in allelic richness （-27.8 %）. Number of founders seemed to have an effect but it also indicated that high population growth rate could help to retain genetic diversity, i.e. future management actions could be effective even with a limited number of founders if population growth would be enhanced. On the contrary, translocated organisms with longer generation times did not seem to retain more genetic diversity. We advocate that, where possible, future studies on translocated animals should report the loss of genetic diversity （both heterozygosity and allelic richness）, which is essential for meta-analyses like this one for deepening our understanding of the genetic consequences of assisted colonization, and justifying management decisions [Current Zoology 61 （5）： 827-834, 2015].
