Prehistoric insects are various groups of insects that lived before recorded history. Insects inhabited Earth since before the time of the dinosaurs. Many modern insects had already evolved to very similar forms even before the dawning of the dinosaur and lived alongside them and beyond up to the present day. Like today, prehistoric insects were an important part of the food chain in their time.
The differences between modern and prehistoric varieties are not great, except that, like many other creatures of prehistory, the latter tended to be much larger than their contemporary equivalents. This size difference is thought to be due to higher atmospheric oxygen levels (allowing diffusion through spiracles over greater distances) and higher temperatures (enhancing metabolism).
Since insects have chitin exoskeletons rather than mineralized bones, few specimens have been found compared to the fossils of much larger vertebrates such as dinosaurs — chitin decomposes more quickly than bone and fossilizes less readily. Most insect remains are found preserved in the hardened sap of ancient trees (amber).
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| Basilosaurus was a genus of cetacean that lived from 40 to 37 million years ago in the Eocene. Its fossilized remains were first discovered in the American South, and were initially believed to be some sort of reptilian sea monster, hence the suffix "saurus"... |
| Coleoptera |
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| A mammoth (from Russian ìàìîíò) is any of a number of an extinct genus of elephant, often with long curved tusks and, in northern species, a covering of long hair. They lived during the Pleistocene epoch from 1.6 million years ago to around 10,000 years ago... |
| Diptera |
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| The term saber-toothed cat describes numerous cat-like species that lived during various parts of the Cenozoic and evolved their saber-toothed characteristics entirely independently. The saber-tooth morphology is an excellent example of convergent evolution as it occurred repeatedly and independently in at least four distinct mammalian groups... |
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