Doctoral Dissertation Improvement: Comparative Positional Behavior of Asian Hominoidea.

在树栖环境中，身体大小是一个主要的制约因素，直立的(直立)运动和姿势行为被认为为相对大型的类人猿(类人猿)的进化发展带来了实质性的优势。这项研究的结果将扩大目前对类人猿，特别是长臂猿位置行为的理解。此外，作为极度濒危的苏门答腊猩猩的资源竞争对手，关于濒危同域长臂猿的位置行为、森林利用和觅食/觅食策略的数据是印度尼西亚北苏门答腊岛西巴塘托罗(WBT)保护战略的关键组成部分。这项研究还与一个更大的关于WBT生物多样性的项目相结合，该项目涉及不同专业的当地和国际研究人员，因此也将促进跨国家和跨学科的联系。最后，Co-Pi将帮助教育印度尼西亚学生和周围的当地社区关于WBT及其生态效益的知识。虽然研究已经解决了身体大小和位置行为如何在这一分类学群体中的最大代表之间存在差异，但关于小型海球类的这种关系的报道要少得多。这是特别有趣的，因为这些在解剖学和行为上专门的灵长类被认为代表了一个谱系，它已经进化地缩小了身体尺寸，并微调了广义正交系的类人猿模式，以便更有效地利用树栖树冠。作为对这一假设的检验，WBT研究了大小可变的共域长臂猿(Hylobates Agilis)和暹罗长臂猿(Symphalangus Syndactylus)的体型、栖息地利用和位置行为之间的关系。之前由泰国Kao Yai国家公园的Hylobates Lar联合PI收集的数据也用于比较。此外，为了重新评估类人猿的运动和姿势特化，本研究还将该研究的数据与之前发表的其他类人猿、环状类人猿、头骨类人猿和脊椎动物的数据进行了比较。

Body size is a major constraint in the arboreal milieu, and orthograde (upright) locomotor and postural behaviors are thought to have conveyed substantial advantages to the evolutionary development of the relatively large-bodied apes (hominoids). The results from this study will expand the current understanding of hominoid, especially gibbon, positional behavior. Additionally, as resource competitors of the critically endangered Sumatran orangutan, data on the positional behavior, forest use, and feeding/foraging strategies of endangered sympatric gibbons represents a key component to the conservation strategies at West Batang Toro, North Sumatra, Indonesia (WBT). This study also integrates with a larger project on the biodiversity of WBT, involving local and international researchers with diverse specializations, and will therefore also facilitate cross-national and inter-disciplinary ties. Lastly, the Co-PI will help educate Indonesian students and surrounding local communities about WBT and its ecological benefits. While studies have addressed how body size and positional behavior covary among the largest representatives of this taxonomic group, far less has been reported on this relationship for the small-bodied hylobatids. This is particularly interesting as these anatomically and behaviorally specialized primates are thought to represent a lineage that has evolutionarily reduced in body size and fine-tuned the ape pattern of generalized orthogrady in order to more efficiently exploit the arboreal canopy. As a test of this hypothesis, the relationships between body size, habitat use, and positional behavior of size-variable sympatric gibbons (Hylobates agilis) and siamangs (Symphalangus syndactylus) are examined at WBT. Previously collected data by the Co-PI for Hylobates lar from Khao Yai National Park, Thailand is also used for comparison. Additionally, data from this study are compared with previously published data for other hominoids, atelids, cebids, and cercopithecoids in order to reevaluate ape locomotor and postural specializations.