“I picture it as sort of a wet BandAid,maybe used inside in operations-like using a piece of tape to close a cut,”he adds.“Gluing things together underwater is not easy.Have you ever tried to put a BandAid on in the shower?This insect has been doing this for 150 million to 200 million years.”
There are thousands of caddisfly species worldwide.Some species spend their larval stages developing underwater,and build an inchlong,tubeshaped case or shelter around themselves using sticky silk and grains of rock or sand.Other species use silk,small sticks and pieces of leaves.Each larva has a head and four legs that stick out from the tube.The larval case gets wider as the larva grows.A caddisfly larva eventually pupates(化蛹)as it develops into an adult fly and then hatches.
Caddisflies now live around the world in waters ranging from fast streams to quiet lowlying wet land.The caddisflies’ adaptation to diverse habitats is largely due to the inventive use by their larva of underwater silk to build complex structures for protection and food gathering.
Caddisflies fall into two groups.Some build their case and then drag it along with them underwater as they search for food.Some build a shelter glued to a rock,with a silk net to catch passing food.
本文是一篇资讯报道。石蛾的幼虫能够吐丝,这种丝的特别之处在于它能够在水下照样具有黏性。如果进行具体的研究,它们将被用于医疗方面。
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