Not so crowded? New findings on global species richness

Earth may contain millions fewer species than previously thought and estimates are converging. Professor Nigel Stork of Griffith’s Environmental Futures Research Institute reveals findings that narrow global species estimates for beetles, insects and terrestrial arthropods.
The research features an entirely new method of species calculation derived from samples of beetles from the comprehensive collection at London’s Natural History Museum.
"It has been said we don’t know to the nearest order of magnitude just how many species with which we share the planet. Some say it could be as low as two million; others suggest up to 100 million," says Professor Stork.
"By narrowing down how many species exist within the largest group, the insects and other arthropods, we are now in a position to try to improve estimates for all species, including plants, fungi and vertebrates.
"Understanding how many species there are and how many there might have been is critical to understanding how much humans have impacted biodiversity and whether we are at the start of, or even in the middle of, an extinction crisis."
About 25 per cent of all species that have been described are beetles. However, when combined with other insects the figure climbs to more than half of all described and named species on Earth.
For this reason, Professor Stork and his colleagues focused on asking how many species of beetles and insects there actually are, in the process applying a new method of estimation arising from a tendency for larger species of British beetles to be described before smaller species.