A new evolutionary study has shown. that beetles are much stronger than we thought and first appeared on Earth at the same time as the earliest dinosaurs and survived until our time Today, there are an estimated 350,000 known species of beetle on Earth, and probably several million more yet to be discovered, say scientists. The insects account for about a quarter of all life forms on the planet.
The new research shows that modern beetle lineages go back further than anyone suspected, even pre-dating the emergence of flowering plants. Previously it had been assumed that the beetles' success story was partly due to flowers which started to bloom in the Cretaceous period, from around 140 million years ago.
Flowering plants were thought to have provided beetles with new sources of food and habitats.
But according to the latest findings many of today's beetle families originated during the earlier Jurassic period, which also saw the appearance of the first major groups of dinosaurs.
Beetles first entered the fossil record in the Lower Permian period, nearly 300 million years ago.
Study leader Professor Alfried Vogler, from Imperial College London and the Natural History Museum, said: "The large number of beetle species existing today could very well be a direct result of this early evolution and the fact that there has been a very high rate of survival and continuous diversification of many lineages since then."
Prof Vogler's team used DNA sequencing and fossil records to compile a comprehensive evolutionary "family tree" for beetles.
By comparing the DNA of 1,880 different beetle species, the scientists were able to identify those which descended from a common ancestor. Fossils of known ages were used to date key moments of evolution and diversification on the ancestral tree.
While the dinosaurs became extinct 65 million years ago, beetles have continued to flourish, evolving into a plethora of different shapes and sizes.
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