Grasshoppers are insects of the suborder Caelifera within the order Orthoptera , which includes crickets and their allies in the other suborder Ensifera . They are likely the oldest living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago. Grasshoppers are typically ground-dwelling insects with powerful hind legs which enable them to escape from threats by leaping vigorously. They are hemimetabolous insects (they do not undergo complete metamorphosis ) which hatch from an egg into a nymph or "hopper" which undergoes five moults , becoming more similar to the adult insect at each developmental stage. At high population densities and under certain environmental conditions, some grasshopper species can change colour and behaviour and form swarms. Under these circumstances they are known as locusts . Insects in the group are plant-eaters, with a few species at times becoming serious pests of cereals, veg...
A spider web , spiderweb , spider's web , or cobweb is a device created by a spider out of proteinaceous spider silk extruded from its spinnerets, generally meant to catch its prey. Spider webs have existed for at least 100 million years, as witnessed in a rare find of Early Cretaceous amber from Sussex, southern England.Insects can get trapped in spider webs, providing nutrition to the spider; however, not all spiders build webs to catch prey, and some do not build webs at all. " Spider web " is typically used to refer to a web that is apparently still in use, whereas " cobweb " refers to abandoned (i.e. dusty) webs. However, "cobweb" is used to describe the tangled three-dimensional web of some spiders of the Theridiidae family. While this large family is also known as the tangle-web spiders, cobweb spiders and comb-footed spiders, they actually have a huge range of web architectures.
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