近日，南非開普敦大學的生物學家Mike Picker和同事日前在《生物學快報》網絡版上發(fā)表的一研究成果"A cockroach that jumps",，稱他們發(fā)現(xiàn)一種會跳高的蟑螂,。
盡管被發(fā)現(xiàn)者起了個“跳螂”的綽號，但Saltoblattella montistabularis很可能是迄今為止發(fā)現(xiàn)的第一種不但會逃跑,，而且能跳高的蟑螂,。
蟑螂沒有得到太多的尊重，然而隨著在南非發(fā)現(xiàn)的一種新的蟑螂,，這一情況或許將有所變化——這個家伙無論外表還是跳躍,，都與蚱蜢非常相像。
修長且肌肉發(fā)達的后肢使“跳螂”的一蹦可以達到35公分的高度——這幾乎是其體長的50倍。這同時也意味著它們打破了蝗蟲的紀錄,，后者僅能達到20倍于自身體長的高度,。
這一新物種同時還生有圓鼓鼓的眼睛，這在蟑螂中可謂獨一無二,，或許有助于它們在一次跳躍后選擇正確的地點著陸,。
迄今為止，生物學家僅僅在開普敦市平頂山國家公園的一小塊草地中發(fā)現(xiàn)了這種“跳螂”,。
研究人員認為,，它可能把跳躍作為一種最簡單的方式來通過生有長草莖的棲息地。（生物谷bioon.com）
doi:10.1098/rsbl.2011.1022
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A cockroach that jumps
Mike Picker1,*, Jonathan F. Colville1,2 and Malcolm Burrows3
We report on a newly discovered cockroach (Saltoblattella montistabularis) from South Africa, which jumps and therefore differs from all other extant cockroaches that have a scuttling locomotion. In its natural shrubland habitat, jumping and hopping accounted for 71 per cent of locomotory activity. Jumps are powered by rapid and synchronous extension of the hind legs that are twice the length of the other legs and make up 10 per cent of the body weight. In high-speed images of the best jumps the body was accelerated in 10 ms to a take-off velocity of 2.1 m s−1 so that the cockroach experienced the equivalent of 23 times gravity while leaping a forward distance of 48 times its body length. Such jumps required 38 µJ of energy, a power output of 3.4 mW and exerted a ground reaction force through both hind legs of 4 mN. The large hind legs have grooved femora into which the tibiae engage fully in advance of a jump, and have resilin, an elastic protein, at the femoro-tibial joint. The extensor tibiae muscles contracted for 224 ms before the hind legs moved, indicating that energy must be stored and then released suddenly in a catapult action to propel a jump. Overall, the jumping mechanisms and anatomical features show remarkable convergence with those of grasshoppers with whom they share their habitat and which they rival in jumping performance.
