The great silk alternative: multiple co-evolution of web loss and sticky hairs in spiders.
The great silk alternative: multiple co-evolution of web loss and sticky hairs in spiders.
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DOI：
10.1371/journal.pone.0062682
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Gorb SN
中科院分区：
文献类型：
--
作者：
Wolff JO;Nentwig W;Gorb SN
蜘蛛是节肢动物中最重要的陆生捕食者。它们在生态上的成功体现在高度的生物多样性和对几乎每一个陆地栖息地的征服上。蜘蛛与丝密切相关，丝是一种材料，通常被认为是蜘蛛巨大的生态成功的原因，并在生命科学中获得了高度关注。然而，人们经常忽视的是，超过一半的新近蜘蛛物种已经放弃了建网或从未发展出这样的适应。这些物种肯定已经找到了其他更经济的猎物捕获和留存解决方案，以补偿增加运动活动带来的更高的能源成本。在这里，我们证明了毛状粘附垫(镜片)与流浪生活方式的汇聚进化密切相关，导致了高度多样化的谱系，至少与衍生的网络建筑类群具有同等的重要性。以前的研究经常强调视镜具有辅助运动的主要功能，而忽略了这样一个事实，即只有最远端的爪垫(爪丛)适合于这些目的。以前的观察，即望远镜用于捕获猎物，在很大程度上被忽视了。我们的结果表明，在控制猎物方面，眼镜片进化成了丝的替代品，在大多数情况下，爪毛是一种二次发育。进一步讨论了特化爪丛的进化趋势和它们的组成，从少量的扩大的刚毛到密集的细长的排列，以及这些脚垫的二次损失。对粘连刚毛的起源及其在进化过程中的多样性提出了假说。
Spiders are the most important terrestrial predators among arthropods. Their ecological success is reflected by a high biodiversity and the conquest of nearly every terrestrial habitat. Spiders are closely associated with silk, a material, often seen to be responsible for their great ecological success and gaining high attention in life sciences. However, it is often overlooked that more than half of all Recent spider species have abandoned web building or never developed such an adaptation. These species must have found other, more economic solutions for prey capture and retention, compensating the higher energy costs of increased locomotion activity. Here we show that hairy adhesive pads (scopulae) are closely associated with the convergent evolution of a vagrant life style, resulting in highly diversified lineages of at least, equal importance as the derived web building taxa. Previous studies often highlighted the idea that scopulae have the primary function of assisting locomotion, neglecting the fact that only the distal most pads (claw tufts) are suitable for those purposes. The former observations, that scopulae are used in prey capture, are largely overlooked. Our results suggest the scopulae evolved as a substitute for silk in controlling prey and that the claw tufts are, in most cases, a secondary development. Evolutionary trends towards specialized claw tufts and their composition from a low number of enlarged setae to a dense array of slender ones, as well as the secondary loss of those pads are discussed further. Hypotheses about the origin of the adhesive setae and their diversification throughout evolution are provided.