Deputy Head of the Griffith School of Environment, Professor Stork said a number of misconceptions have fueled these fears, and there is no evidence that extinction rates are as high as some have feared.

"Surprisingly, few species have gone extinct, to our knowledge. Of course, there will have been some species which have disappeared without being recorded, but not many we think," Professor Stork said.

Professor Stork said part of the problem is that there is an inflated sense of just how many animals exist and therefore how big the task to record them.

"Modern estimates of the number of eukaryotic species have ranged up to 100 million, but we have estimated that there are around 5 million species on the planet (plus or minus 3 million)."

And there are more scientists than ever working on the task. This contrary to a common belief that we are losing taxonomists, the scientists who identify species.

"While this is the case in the developed world where governments are reducing funding, in developing nations the number of taxonomists is actually on the rise.

"World-wide there are now two to three times as many taxonomist describing species as there were 20 years ago."

Even so, Professor Stork says the scale of the global taxonomic challenge is not to be underestimated.

"The task of identifying and naming all existing species of animals is still daunting, as there is much work to be done."

Other good news for the preservation of species is that conservation efforts in the past few years have done a good job in protecting some key areas of rich biodiversity.

But the reprieve may be short-lived.

"Climate change will dramatically change species survival rates, particularly when you factor in other drivers such as overhunting and habitat loss," Professor Stork said.

"At this stage we have no way of knowing by how much extinction rates may escalate.

"But once global warming exceeds the 2 degree barrier, we can expect to see the scale of loss many people already believe is happening. Higher temperature rises coupled with other environmental impacts will lead to mass extinctions"

Story Source:

Materials provided by Griffith University. Note: Content may be edited for style and length.

Journal Reference:

1. M. J. Costello, R. M. May, N. E. Stork. Can We Name Earth's Species Before They Go Extinct? Science, 2013; 339 (6118): 413 DOI: 10.1126/science.1230318