What accounts for 25% of all living things on Earth? Beetles. They are some of the most successful creatures to have lived and new research published in the journal Science today suggests that they may also be the most enduring.
Scientists at the Natural History Museum and Imperial College have discovered that most modern-day beetle groups first appeared during the Jurassic period at the time when the major groups of dinosaurs appeared too.
These beetle groups out-lived the dinosaurs and diversified into the 350,000 species we see today. There are probably several million more species still to be discovered.
'The large number of beetle species existing today could very well be a direct result of this early evolution of many modern-day lineages,' says Professor Alfried Vogler, lead scientist on the study. 'There has been a very high rate of survival and continuous diversification of many lineages since then.'
The team studied the DNA of 1,880 species of beetles and was able to produce an evolutionary family tree. This helped them look at the relationship between different species and identify common ancestors.
Fossil data was then used to obtain key dates in evolution history. This is the most extensive beetle evolutionary study carried out to date.
Beetles are extremely good at adapting to new ecological environments, changing their life styles and feeding habits when acquiring new surroundings. For many years scientists have debated why beetles are such successful survivors.
'Unlike the dinosaurs, which dwindled to extinction, beetles survived because of their ecological diversity and adaptability," Vogler says.
One theory for the beetles' success has been the fact that they are herbivores (eat plants). It is thought that beetles diversified around the time flowering plants diversified in the Cretaceous era wihch provided a new resource for the beetles. The flowering plants first originated around 140 million years ago and this new research shows beetles had already diversified long before this time.
Understanding the evolution of beetles is an important part of understanding the natural world, such as the evolution of other life forms and how diversity evolves.
'With beetles forming such a large proportion of all known species, learning about their relationships and evolution gives us important new insights into the origin of biodiversity and how beetles have triumphed over the course of nearly 300 million years,' Vogler concludes.