Sunday, October 26, 2008

Rick West: the Tarantula GOD

Tarantulas are the largest and most revered of all spiders, comprising just over 900 species in the mygalomorph family Theraphosidae. The Venezuelan tarantula Theraphosa apophysis (Tinter 1991) attains a straightened diagonal leg span of just over 28 cm (11 inches), a little larger than a dinner plate. While not quite as long-legged, the female South American species Theraphosa blondi (Latreille 1804) has a heavier body with an abdomen that can equal the size of a tennis ball and have an impressive bodyweight of 125 grams (1/4 pound) with fangs that can be nearly 2 cm (3/4 inch) in length. One of the smallest known tarantulas, Aphonopelma paloma Prentice 1993, found in Arizona, has a total adult body length of 8 mm (1/3 inch).


Rick West eating tarantulas
Tarantulas have been the maligned victims of a great deal of popular lore that bely that they are generally mild mannered, handsomely colored and beneficial. Several cultures throughout the world catch, cook and eat the larger ground-dwelling tarantulas as a valuable nutritional supplement. I can tell you, from personal experience, that a cooked tarantula tastes similar to a prawn.

Sadly, most people still regard tarantulas as the things that nightmares and horror movies are made of. They have become synonymous with creepy crawly creatures of Halloween or have unjustly earned the reputation as being deadly poisonous. To date, there are no documented medical cases on file of a single human fatality resulting directly from the bite (envenomation) of any tarantula species. Tarantulas, like all spiders, are not aggressive; they are defensive and will either run away or stand and defend themselves if molested. A tarantula bite, through painful, can have a range of effects on a human from slight noticeable pain and edema to a comatose effect (extremely rare). Only a small number of tarantula species have had their venom studied and scientists still do not know if any species can be potentially lethal to humans. What researchers have, however, found is that some of the properties of tarantula venom may hold uses in treating such human medical conditions as heart arrhythmia, Parkinson’s and Alzheimer disease as well as have agricultural uses in pesticide applications.


Some people have a genuine fear of spiders, including tarantulas, called arachnophobia. This phobia is an anxiety disorder which is curable. Patients have received treatment at the Stanford University School of Medicine and the University of Washington, whereby, part of the therapy involves the eventual handling of a live ‘pet' tarantula.


Suffice it to say, tarantulas have been the subject of distain in human cultures throughout the world for hundreds of years. However, in the past several decades, tarantulas have become very popular and sought after as exotic pets.

‘Tarantula Societies’ have sprung up all over the world and the quest to bring new and colorful tarantulas to the pet trade is growing. To their credit, along with dispelling many of the age old misconceptions held with tarantulas, there have been many new species found, along with an increase in knowledge on improved care, keeping and breeding in captivity.

In myth, tarantula spiders have been affiliated with deities or themselves been considered to possess spiritual powers or meaning. While some indigenous cultures regard all spiders, including tarantulas, as very wise or cunning tricksters others specifically regard ground-dwelling tarantulas as guardians or messengers of the literal pathway between the spirit underworld and the natural world. It is amazing to find references of so many unrelated cultures throughout the world believing that ground-dwelling tarantulas are guardians of portals (their burrow) which link the seeker (shaman) with either their ancestral dead or an underworld deity.


Tarantulas guarding central portal to
underworld, Embera mola art
The name tarantula originated around the 14th century from two genera of poisonous spiders, Lycosa (Wolf spiders) and Latrodectus (Widow spiders), found on the outskirts of the Italian city of Taranto in the State of Apulia. People believed anyone bitten by such a spider would die unless that person went into a hysterical, self-hypnotic state known as tarantism. Tarantism was supposed to give the bitten victim the inordinate desire to dance erotically. Not surprisingly, old records revealed most tarantati victims were usually late adolescent women claiming to be bitten in immodest body regions during the summer harvest months. Early investigators found that some women had recurring attacks of tarantism on the anniversary of their first bite which sometimes went on for years. The people of the time thought the disease was contagious and that the only cure was music of a specific kind which would incite the victim to dance provocatively to wear off the effects of the poison and the more people that could join in this dance, the faster the victim would be ‘cured’. Often the tarantists sang sexually explicit themes while they danced, sometimes lasting anywhere from several days to two weeks. It is now believed these ritual dances were a convenient excuse to carry on lewd rites, banned by the Christians, for the release of suppressed erotic energy in a time of poverty, boredom and a sexually repressive rural life. Variations of tarantism and the tarantella could be found throughout the Mediterranean region between the 14th and 17th century.


Wolf spider
During the late 1950's, an Italian ethnosociologist still found tarantati victims who went every year on June 28 & 29th to the chapel and holy well of St. Paul in Galatina, Italy, to seek a cure from the tarantism. In earlier times, St. Paul had become the patron saint for tarantula bite victims. Paradoxically, St. Paul was reported not only to be able to cure bite victims but sent tarantulas to bite sinners! With the replacement of televisions and other cultural changes the only evidence tarantism existed can be found as a tuneful dance at an occasional rural social function or in one of several classical music themes like ‘La Tarantella - Antidotum Tarantulae’.

Early Europeans who immigrated to America and pioneered their way to the south-west United States often saw and referred to the large hairy mygalomorph spider as a `tarantula' and the term has been used ever since. Today, the name tarantula is used primarily in all English-speaking parts of the world and includes all those mygalomorph spiders in the family theraphosidae.


Tarantella music sheet
Another commonly used name for a tarantula spider arose from explorers returning to Europe from the Far East and Latin America in the eighteenth and nineteenth century. Some of the explorers were naturalists who not only exaggerated the size of these spiders by stating they'd seen native children walking tarantulas tied on a piece of vine like a `small Pekinese dog on a leash’ but also stated they'd seen tarantulas sucking the blood of birds in trees. The arboreal tarantula was referred to as `bird-eating spider' or `bird-spider'.

In 1705, a German naturalist named Maria Sybilla Merian presented a folio in Amsterdam on the insects of Surinam entitled Metamorphosis Insectorum Surinamensium. In this work, Madam Merian published and illustrated her eyewitness account of a South American tree-dwelling tarantula, presumably an Avicularia, eating birds! At that time it was unimaginable for people to believe that not only could a spider catch and eat a bird but that a tarantula could live in a tree, especially from a woman in a time when the scientific community was dominated by men.


Larger bird-eating tarantula eating
bird on ground
It was over a hundred years after Madam Merian's published account that these bird-eating spiders became more believable. In 1817, while travelling on the Caribbean islands of Martinique and Guadeloupe, Monne de Jonnes stated in Bulletin de la Societe Philomathique he saw arboreal Avicularia tarantulas preying on lizards (Anolis sp.), hummingbirds (Colibri sp.) and a relative of the tree-creeper bird. These stories were often portrayed by artist's conceptions of what had been reportedly seen. In 1834, W.S. MacLeay tried to discredit Madam Merian's earlier account by placing a live hummingbird and an Anolis lizard in the burrow of a ground-dwelling tarantula. MacLeay found not only did the tarantula ignore the prey but fled the burrow, thus, drew the conclusion these earlier reports of bird-eating spiders were false and stated tarantulas were only capable of eating insects. In 1863, naturalist Henry Walter Bates published in The Naturalist on the River Amazons that he had witnessed the same predation on small birds by Avicularia tarantulas in the Brazilian jungles. In 1899, Reginald Pocock wrote in Annals and Magazine of Natural History that a naturalist in Borneo had collected an arboreal bird-spider, Phormingochilus tigrinus Pocock 1895 in a bird's nest after having killed the hatchlings.


Smaller bird-eating tarantula eating bird on branch
Since these early reports, a wide variety of tarantulas have been observed catching and eating other small vertebrate creatures such as frogs, snakes, small rodents and bats. French-speaking explorers called tarantulas `mygales' and German-speaking people referred to them as `vogelspinnen' (bird-spider). Today, the name `bird-spider' primarily refers to those tarantulas found in the Australasian region and parts of Latin America.

With the exception of extremely dry habitats that cannot support insect life as an important food source, tarantulas can generally be found between the 45th latitudes around the world with the exceptions of Tasmania, New Zealand, Hawaiian and most of the South Pacific Islands. In the United States, it is believed that tarantulas do not occur north of the Red River or east of the Mississippi River – with the exception of the introduced and established Mexican species Brachypelma vagans Ausserer 1875 in Florida State.


Cave tarantula
Some varieties of tarantula live entirely in trees (arboreal), some live in self-constructed ground burrows (fossorial), others are wandering opportunistic burrowers that will utilize any crevice, fallen debris or abandoned burrow. Tarantulas, such as Hapalotremus, can live as high as 15,000 feet while others, such as Aphonopelma, are found below sea level in the Mojave Desert, California. A few tarantulas, such as the Mexican genus Hemirrhagus (formerly, in part, Spelopelma), live over one mile deep in underground limestone caverns and have evolved without eyes in a world of total darkness (troglobites).


Fossil tarantula
The oldest known tarantula ancestor is Rosamygale grauvogeli Selden & Gall 1992 found in a fossil in France from the Lower Triassic period of 235-240 million years ago. The earliest known tarantula spider is Ischnocolinopsis acutus Wunderlich 1988 found in Dominican amber from the Miocene era of about 20-23 million years ago. Tarantula fossils are scarce and so far there is no evidence to support that tarantulas existed during the dinosaurs 65 millions years ago. It is, however, probable that tarantulas did exist before the dinosaurs. Like other flightless animals dependent on continuity of the land surface for migration, it may be that the aforementioned land areas broke away from the super continent of Gondwanaland before tarantulas reached them. Some land areas, such as the Hawaiian and many of the South Pacific islands were formed by volcanoes or coral buildup and were not part of the separating land masses.

Since that period, tarantulas have remained virtually unchanged. They have survived scores of natural enemies and global changes. Now, with the heavy use of pesticides and agricultural, industrial and urban development that transforms the tarantula’s natural habitat, tarantulas face their biggest threat - man.

No comments:

Post a Comment