Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2021 Mar;207(2):141-152. doi: 10.1007/s00359-020-01453-3. Epub 2020 Nov 23.
Many organisms secrete structural materials from their bodies to enhance protection, foraging or signalling. The function of such secretion products can be further extended by their assembly into complex structures, so-called extended phenotypes, such as shells, nests and biofilms. Understanding the variation in the efficacy of such assembly processes could help to explain why extended phenotypes are common on some lineages and rare in others. Here, I comparatively studied the assembly of sticky silk fibres into thread anchorages by the innate 'printing' behaviour in 92 species of spiders from 45 families, representing the so-far largest comparative study of construction-related motion patterns. I found a global evolutionary trend towards a faster production of silk thread anchorages, in both web builders and hunting spiders. The slowest producers of silk anchors belong to a clade with an ancestral configuration of respiratory organs, suggesting that a major constraint to the evolution of spinning speed is the efficiency of oxygen uptake. Motion patterns were found to contain a high phylogenetic signal, but did not correlate with spinning speeds. These results help to explain the variation in diversity and ecological success among the spider fauna and showcase the value of comparative kinematics in biodiversity studies.
许多生物从体内分泌结构材料来增强保护、觅食或信号传递功能。通过将这些分泌产物组装成复杂的结构，即所谓的扩展表型，如壳、巢和生物膜，可以进一步扩展其功能。了解这种组装过程的效果变化，可以帮助解释为什么扩展表型在某些谱系中很常见，而在其他谱系中则很少见。在这里，我比较研究了 45 个科的 92 种蜘蛛的先天“打印”行为中粘性丝纤维组装成线锚的过程，这是迄今为止对与结构相关的运动模式进行的最大比较研究。我发现，无论是在织网蜘蛛还是在狩猎蜘蛛中，丝线锚的生产速度都呈现出全球性的进化趋势，即变得更快。丝线锚生产最慢的蜘蛛属于一个具有祖先呼吸器官结构的分支，这表明，对纺丝速度进化的主要限制因素是氧气摄取的效率。运动模式表现出很高的系统发育信号，但与纺丝速度无关。这些结果有助于解释蜘蛛动物群中多样性和生态成功的变化，并展示了比较运动学在生物多样性研究中的价值。
