CONPREHENSIVE RESEARCH ON SUBSPECIATION IN AGILE GIBBONS

长臂猿和猩猩一样，都是濒危的亚洲类人猿，因此对每个物种或亚种的基因监测是保护计划的迫切需要。我们开展了一个项目，尽可能地从苏门答腊和婆罗洲（加里曼丹中部）的野生动物中提取已知来源的样本，用于对敏捷的长臂猿进行遗传监测。结果，我们发现了苏门答腊敏捷长臂猿特有的8号和9号染色体（WAT8/9）之间的整个手臂易位。此外，人口调查表明，具有WAT8/9的形式似乎与祖先的形式不相容，这表明前者可能通过竞争使后者从苏门答腊种群中灭绝。无论如何，这种易位是识别苏门答腊敏捷长臂猿的一个有用的染色体标记。种群遗传分析表明，苏门答腊敏捷长臂猿和婆罗洲敏捷长臂猿的分子遗传距离最小，但染色体差异最大。因此，我们假设WAT8/9在末次冰期迁移和地理隔离后，在苏门答腊的一个小种群中产生并固定下来，随后由于瓶颈效应和染色体隔离机制迅速扩散到苏门答腊的其他种群中。这里获得的数据可以作为非常有用的遗传标记来识别物种或亚种，这将是保护计划不可或缺的。WAT8/9重排是区分苏门答腊和婆罗洲敏捷长臂猿的重要染色体标记。

Gibbons, like orangutans, are a group of threatened Asian apes, so that genetic monitoring of each species or subspecies is a pressing need for conservation programs. We conducted a project to take, as far as possible, samples of known origin from wild-born animals from Sumatra and Borneo (Central Kalimantan) for genetic monitoring of agile gibbons. As a result, we found a whole arm translocation between chromosomes 8 and 9 (WAT8/9) specific to Sumatran agile gibbons.Furthermore, population surveys suggested that the form with the WAT8/9 seems to be incompatible with an ancestral form, suggesting that the former might have extinguished the latter from Sumatran populations by competition. In any case, this translocation is a useful chromosomal marker for identifying Sumatran agile gibbons. Population genetic analyses with DNA showed that the molecular genetic distance between Sumatran and Bornean agile gibbons is the smallest, although the chromosomal difference is the largest. Thus, it is postulated that WAT8/9 occurred and fixed in a small population of Sumatra after migration and geographical isolation at the last glacial period, and afterwards dispersed rapidly to other populations in Sumatra as a result of the bottleneck effect and a chromosomal isolating mechanism. The data obtained here could be very useful as genetic markers for identifying species or subspecies that would be indispensable to conservation programs. The WAT8/9 rearrangement is a remarkable chromosomal marker for separating Sumatran and Bornean agile gibbons.