Life On a Limb: The Evolution of Locomotion in Arboreal Specialists

肢体上的生命：树栖专家运动的进化

• 批准号: 0120168
• 负责人: Duncan Irschick
• 金额: $ 12.52万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-01 至 2004-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0120168&HistoricalAwards=false
• 关键词: Life; Limb; Evolution; Locomotion; Arboreal

An important goal in ecological and evolutionary physiology is to reveal the underlying mechanisms behind differences in habitat use. Studies of locomotor capacity have played a key role in this goal because many species have evolved locomotor abilities in concert with the use of different habitats. Most studies of locomotion are modeled after relatively simple terrestrial habitats (i.e., broad surfaces), and therefore are not ecologically realistic for arboreal species. However, understanding how variables commonly encountered in arboreal habitats (steep inclines, narrow perch diameters) affect locomotion could provide general insights into specialization to different habitats. The tremendous morphological and phylogenetic diversity of lizards exploiting arboreal habitats makes them ideally suited for studying arboreal locomotion. We propose to build on prior work with a group of eight species of Anolis lizards because their phylogeny is well resolved and these species have been characterized as belonging to distinct ecomorphs that occur in different arboreal habitats. The sprinting performance of these Anolis species has been correlated with limb length and the diameters of surfaces in laboratory studies, but virtually nothing is known regarding how the limbs are used on different surfaces and inclines. Thus, in laboratory studies we will conduct three experiments: (1) Examine the effects of incline and surface diameter on the kinematics of steady-speed locomotion in three species of Anolis lizards. (2) Focus on the effects of surface diameter on the kinematics of steady-speed locomotion in 8 species of Anolis lizards. This second experiment will provide a comparative basis for understanding how surface diameter affects locomotion. (3) Study how acceleration and performance is affected by surface diameter for a group of diverse Anolis species. Together, these experiments will reveal the underlying mechanistic and behavioral bases for why some anole species are affected by incline while others are not. Further, they will provide a valuable link between habitat use and quantitative functional morphology. More generally, we will also test whether function, morphology, and habitat use have co-evolved among species, and whether locomotion in arboreal environments differs from locomotion in terrestrial environments. The second goal will be achieved by comparing data from the proposed experiments to those recently performed on terrestrial lizard locomotion.

生态和进化生理学的一个重要目标是揭示栖息地利用差异背后的潜在机制。对运动能力的研究在这一目标中发挥了关键作用，因为许多物种在利用不同栖息地的同时进化出了运动能力。大多数关于移动的研究都是以相对简单的陆地栖息地(即宽阔的表面)为模型的，因此对树栖物种来说是不现实的。然而，了解树栖生境中常见的变量(陡峭的坡度、狭窄的栖息直径)如何影响运动可以提供对不同生境专门化的一般见解。利用树栖栖息地的蜥蜴具有巨大的形态和系统发育多样性，这使它们非常适合研究树栖动物的运动。我们建议在以前工作的基础上对八种Anolis蜥蜴进行研究，因为它们的系统发育已经很好地解决了，并且这些物种被描述为属于不同的生态形态，出现在不同的树栖生境中。在实验室的研究中，这些Anolis物种的短跑能力与肢体长度和表面直径有关，但关于肢体如何在不同的表面和坡度上使用，几乎一无所知。因此，在实验室研究中，我们将进行三个实验：(1)考察坡度和表面直径对三种Anolis蜥蜴稳速运动运动学的影响。(2)研究了8种蜥蜴体表直径对其稳速运动运动学的影响。第二个实验将为理解表面直径如何影响运动提供一个比较的基础。(3)对一组不同种类的Anolis物种，研究表面直径对加速度和性能的影响。综上所述，这些实验将揭示一些ANONE物种受倾斜度影响而其他物种不受影响的潜在机制和行为基础。此外，它们将在栖息地利用和定量功能形态之间提供有价值的联系。更广泛地说，我们还将测试物种之间的功能、形态和栖息地使用是否共同进化，以及树栖环境中的运动是否与陆地环境中的运动不同。第二个目标将通过将拟议实验的数据与最近在陆地蜥蜴运动上进行的数据进行比较来实现。