Understanding Insects through Fossils
Although it has been estimated that insects account for roughly one-third of all animal species alive today, insects are, on the whole. poorly represented in the available fossil record, where many species are known from just a single specimen, and a high proportion of fossil insects come from exceptional fossil deposits that are sporadically distributed in time and space. Nonetheless, about 40.000 species of insects have been described as fossils, with many more awaiting description. Foremost among insect-rich deposits are ambers in which complete external preservation of insects is routine. Amber is the fossilized resin of a few particular kinds of trees. Oozing out of the bark, this resin had the ability to trap and surround insects, as well as other small animals, protecting them from the normal processes of organic decay as it hardened into transparent, yellow or orange amber. The chemical process of “amberization” could take up to 10million years. During this time, it was common for amber initially buried in the soil to be washed out by rivers and redeposited in the sea.
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