根據(jù)任何物理學(xué)法則,，像狼蛛這樣又大又重的蜘蛛都是不能爬墻或倒掛的——它們應(yīng)當(dāng)會一頭栽到地上。
然而盡管有點費勁,，但狼蛛?yún)s能夠攀爬,，于是研究人員決定找出問題的答案。
他們采集了幾種狼蛛蛻掉的外皮,，其中就包括第一作者本人摯愛的剛剛離世的寵物——毛球（如上圖）,。研究人員發(fā)現(xiàn)，狼蛛毛茸茸的腳底覆蓋著細微的毛發(fā),，其作用相當(dāng)于一根黏絲的“閥門”,，它們只有在狼蛛開始墜落時才被打開。
由于大多數(shù)蜘蛛都會從腹部的吐絲器中制造蛛絲,，因此這一發(fā)現(xiàn)可能有助于解釋蜘蛛是如何將它們的蛛絲進化出這么多的用途的,。
研究人員在6月份出版的《實驗生物學(xué)期刊》上報告了這一研究成果。這還解釋了為什么狼蛛走過的地方總會留下少量絲制的腳印,。（生物谷Bioon.com）
生物谷推薦原文：
The Journal of Experimental Biology DOI: 10.1242/?jeb.055657
Tarantulas cling to smooth vertical surfaces by secreting silk from their feet
F. Claire Rind, Chris Luke Birkett, Benjamin-James A. Duncan1 and Alexander J. Ranken
Like all spiders, tarantulas (family Theraphosidae) synthesize silk in specialized glands and extrude it from spinnerets on their abdomen. In one species of large tarantula, Aphonopelma seemanni, it has been suggested that silk can also be secreted from the tarsi but this claim was later refuted. We provide evidence of silk secretion directly from spigots (nozzles) on the tarsi of three distantly related tarantula species: the Chilean rose, Grammostola rosea; the Indian ornamental, Poecilotheria regalis; and the Mexican flame knee, Brachypelma auratum, suggesting tarsal silk secretion is widespread among tarantulas. We demonstrate that multiple strands of silk are produced as a footprint when the spider begins to slip down a smooth vertical surface. The nozzle-like setae on the tarsi responsible for silk deposition have shanks reinforced by cuticular thickenings, which serve to prevent the shanks' internal collapse while still maintaining their flexibility. This is important as the spigots occur on the ventral surface of the tarsus, projecting beyond the finely divided setae of the dry attachment pads. We also reveal the structure and disposition of the silk-secreting spigots on the abdominal spinnerets of the three tarantula species and find they are very similar to those from the earliest known proto-spider spinneret from the Devonian period, giving another indication that silk secretion in tarantulas is close to the ancestral condition.
