Ruminations

The Itty-Bitty Spider

"It is also hoped ultimately to assemble complete case histories of several individual nests [of trap-door spiders]." 1977 report
"[To track and identify] A life-cycle of perhaps twenty years notwithstanding."
"I wanted to know how long the spiders lived."
"Although adult nests frequently have their doors and twig-lines torn off [presumably by birds] none appear to have been seriously affected by this. The spiders reattach their doors, sometimes upside down or back-to-front and attach new twig-lines." 1978 report.
Barbara Main, arachnid researcher, Australia

"We spend three hours on our knees as Barbara checks each burrow to see if it's occupied or not"
"She observes, with a mild air of concern, how few new trap door burrows there are and how unseasonably dry the reserve is [where they are located]."
"Inside, I can just see the spider, which has pulled a veil of silk lining half across its burrow. Under my breath, I introduce myself and wish her well."
Vicki Laurie, Australian Broadcasting Corp. reporter, 2013

"She was going to finish the study when number 16 died. She was going to write it up as a big thing."
"She [the legendary, long-lived southwest Australian Gaius villosus trap-door spider] was cut down in her prime. It took a while to sink in, to be honest."
"Number 16 was out in the bush, which is even more impressive because we all know that animals living captivity can live longer, perhaps, than those in the wild."
"We can be inspired by an ancient megalomorph spider and the rich biodiversity she embodied."
Leanda Mason, ecologist, Curtin University, 2016

This is a female trapdoor spider from a longterm population study in Australia. Another spider from the same study, called Number 16, died at the age of 43. It was the oldest known spider the world. (Submitted by Leanda Mason)

A spider, a tiny, blind, secretive spider living to eat and to breed and doing so in the perpetuation of her species for 43 years. Living in a minuscule burrow she herself dug before she was a year old, after having lived in her mother's burrow for the first six months of her life, without once exiting it, until finally her mother did and Spider 16 and her dozens of sibling spiders also left, to embark on a life of their own, for as long as they could survive through the vagaries of weather conditions and predators.

Spider 16 was named thus by zoologist Barbara Main in 1975, when the spider was already a year old. She had built her nest just as her mother before her had done, as an infinitesimally small tunnel-burrow, lined with silk and where she would live in the soil in the dark in a hollow sufficiently large to contain her tiny body, and no larger. As she grew she would enlarge the burrow, but it would always be tiny because she was, a fraction of an inch across.

This first home would be Spider 16's only and permanent home within the North Bungulla Reserve in Australia. After lining her burrow with silk, she wove a door of silk to stretch across the mouth of her home, and attached it with a hinge to one side of the opening. Then she hauled countless tiny twigs to the doorway's edge one after another, laying them precisely to radiate from the opening like blades of a fan, from inherited memory.

Spider 16 retreated within her burrow and there she stayed, after closing the door that would only be opened when vibration above betrayed to the tiny blind animal that something was moving among the twigs at which point she leaped out and drew into her nest an ant or a tiny beetle or mayfly. She is one of dozens of trap door spider species in the wilderness areas of the Australian wheat belt.

She started being tracked when Barbara Main set out to find, label and track her species in 1975, and placed beside her nest a small, very small, metal sign engraved with the numeral "16", identifying the spider as one of hundreds that would eventually be discovered and personalized with a number. This zoologist with the University of Western Australia marking every burrow she found of Gaius villosus, then reported her intention in 1977 to the International Congress of Arachnology of discovering their longevity potential.

Gaia, of course, is what we call Mother Earth. All of the burrows with their spider-residents were located within a few metres of one another, close to an old gravel pit, under an Acacia tree. The scientist noted when Spider 16's mother and siblings died, but number 16 lived on. Eventually a reporter with ABC broadcasting heard of an elderly scientist who had tracked a spider for four decades and asked to accompany her on her next foray.

It was explained to the reporter that females lived in their burrows, never emerging but briefly to bring in prey, until they died. And on their death no other spider would take possession of the empty nest. Soon after their joint expedition to assess the spiders' health and presence which Dr. Main had done for forty years, an aspiring doctoral candidate joined them as an aide to Dr. Main who continued to catalogue the generations of spiders.

The zoologist, however, finally retired in her late 80s last year, succumbing to ill health and the inability to get around as she once did to pursue her investigations. Mason, studying for her doctorate in ecology, inherited the project and continued to study the spiders until in 2016 she went out for field work to the reserve to check on Spider 16. To discover that the twigs around the burrow door were in disarray.

A tiny hole was seen in the centre of the silk door. Lifting the door, Ms. Mason lowered an endoscope into the burrow and her suspicions were confirmed. A parasitic wasp had in all likelihood broken through the silk seal to lay its eggs in 16's body. And the venerable spider became a sustaining meal for the developing wasps as they matured from egg to larvae to wasp.

Spider 16 had lived for a remarkable and unexpected 43 years before she succumbed to the order of nature. Male trapdoor spiders, on the other hand, die as soon as they impregnate a female That too is nature's order.