They lurk in pillows beneath your head, deep in the ocean, in human facial pores and even on forest mushrooms and penguin corpses in the Antarctic.
They're very small creatures called mites, and while more than 40,000 species have been described, there could be up to one million species on our planet.
That's enough to create many lifetimes of work for acarologist (mite expert) Dr David Walter of The University of Queensland's Zoology and Entomology Department.
Dr Walter is leading a number of Australian Research Council, Australian Quarantine Inspection Service, Australian Biological Resources Study and CUTSD-funded projects to explore the diversity and importance of these tiny creatures, whose significance often escapes trained biologists.
He has discovered new species in Australian rainforests, including two families of mites previously unknown anywhere in the world: one is an unnamed family of mites that jumps in the face of danger.
But there is a large backlog of undescribed species. Fewer than 3000 mite species have been described in Australia - perhaps only three percent of the total acrofauna - as most acarologists are in the Northern Hemisphere.
"Because of their economic importance, we will always need to understand mites, but the study of mites - acarology - is a disappearing science," he said. "Mites are fascinating creatures themselves, and a major component of biological diversity. Many species can cause problems when feeding on humans, our crops and domestic animals, and many in turn feed on what we consider to be pests."
Branches of the mite family include asthma-inducing dust mites, paralysis ticks, scrub itch mites, crop pests, and many species with potential as biological controls for pests such as nematodes and white fly. Then there are the feral mites, spreading outside their natural habitat, of particular interest to quarantine authorities and resource managers.
Dr Walter is one of only a handful of acarologists in the world, and is trying to keep the discipline alive in Australia as science is swept by molecular mania. The country once hosted a thriving nucleus of acarologists, but Dr Walter believes he may be the last academic in the country teaching the study of mites.
"I feel like a Medieval monk, keeping the illuminated manuscripts safe during the Dark Ages," Dr Walter said.
"Their size is against them," he said. "The smallest are about 80 microns, or in other words you can lay a dozen of them end to end to make a millimetre. The biggest is 16mm."
"Humans are relatively large vertebrate animals, and not surprisingly, we tend to relate best to organisms that approach us in size and similarity of form. Mammals, birds, reptiles and even fish are usually recognised and valued as animal life, but what of the worms, slugs, bugs, maggots, mites and the like that inhabit an area.
"Unfortunately for our preconceptions, these invertebrate animals are not only the bulk of biological diversity but an integral part of all food webs that allow ecosystems to function and communities of organisms to co-exist."
Dr Walter has developed a gallery of cool mite images on the World Wide Web to attract students to his specialty. The mite image gallery at: http://www.uq.edu.au/entomology/mite/mitetxt.html has received rave international attention since its review in prestigious international journal Science late last year.
Dr Walter and his wife Dr Heather Proctor of Griffith University have recently authored Mites: Ecology, Evolution and Behaviour (University of New South Wales, $95), written to stimulate student interest in some of the tiniest and most diverse creatures on Earth.
With Committee for University Teaching and Staff Development (CUTSD) funding, he is also developing keys for teaching students about mites using an interactive LucID computer program. Research supported by the Australian Biological Research Society and Lamington National Park is furthering study of rainforest species.
Media: Further information, Dr David Walter, telephone 3365 1564, email d.walter@mailbox.uq.edu.au
