A huge number of new species of invertebrate animals have been found living in underground water, caves and micro-caverns amid the harsh conditions of the Australian outback.
Insects, crustaceans, spiders, worms and many others are among 850 species found by a national team of 18 researchers, according to the University of Adelaide.
The team--led by Andy Austin, from the University of Adelaide, Steve Cooper of the South Australian Museum, and and Bill Humphreys of the Western Australian Museum--has conducted a comprehensive four-year survey of underground water, caves and micro-caverns across arid and semi-arid Australia, the university said in a statement about the discovery.
"What we've found is that you don't have to go searching in the depths of the ocean to discover new species of invertebrate animals--you just have to look in your own 'backyard'," says Austin, who is a professor at the Australian Center for Evolutionary Biology & Biodiversity at the University of Adelaide.
"Our research has revealed whole communities of invertebrate animals that were previously unknown just a few years ago. What we have discovered is a completely new component to Australia's biodiversity. It is a huge discovery and it is only about one fifth of the number of new species we believe exist underground in the Australian outback."
Phreatomerus latipes, a freshwater ispod from Mound Springs, South Australia--previously thought to be a single species but now known to be eight different species, seven of them new.
Only half of the species discovered have so far been named, according the University of Adelaide says. Generically, the animals found in underground water are known as "stygofauna" and those from caves and micro-caverns are known as "troglofauna", the university explained.
Austin says the team has a theory as to why so many new species have been hidden away underground and in caves.
"Essentially what we are seeing is the result of past climate change...Species took refuge in isolated favorable habitats, such as in underground waters and micro-caverns, where they survived and evolved in isolation."
"Essentially what we are seeing is the result of past climate change. Central and southern Australia was a much wetter place 15 million years ago when there was a flourishing diversity of invertebrate fauna living on the surface.
"But the continent became drier, a process that last until about 1-2 million years ago, resulting in our current arid environment. Species took refuge in isolated favorable habitats, such as in underground waters and micro-caverns, where they survived and evolved in isolation from each other.
Some of the 850 new species discovered in underground water, caves and micro-caverns across outback Australia.
Copyright © 2009 The University of Adelaide
"Discovery of this 'new' biodiversity, although exciting scientifically, also poses a number of challenges for conservation in that many of these species are found in areas that are potentially impacted by mining and pastoral activities," he says.
The research team reported its findings last week at a scientific conference on evolution and biodiversity in Darwin, which celebrated the 200th anniversary of Charles Darwin.
The research was funded in part by the National Geographic Society's Committee for Research and Exploration.
By the 
