POISON ARROW FROGS
PROGRESS REPORTS
Poisonousness
I am often asked whether poison arrow frogs are really toxic. For offsprings I can deny this. However, hoyden are more or less toxic according to kind. Why is this thus? American researchers have found out it once more!
MITES MAKE FROGS TOXIC
US researchers solve poison secret of the coloured amphibians
Small mites make the arrow poison frogs of Central America toxic. Researchers Florida have found out this Internationally University FIU http://www.fiu.edu. Up to now the scientists knew only that the amphibians cannot produce her poison themselves. However, it was unclear which food is used to the production of the toxins, they report in the latest issue of the science magazine Proceedings of the Nationwide Academy of Sciences PNAS.
The research team around the biologist Ralph Saporito had found some years ago in the stomachs of so-called pumilio exactly those organic alkaloid connections which pointed to ants as food of the animals. However, the ants do not belong to the main food of the frogs. Hence, the scientists have come along on the search for those animals who can produce such alkaloids. Successfully the researchers became with the horn-rimmed mites (Oribatida). Alkaloids are connections which have a very strong effect on living organisms - many of it are very toxic. Caffeine and nicotine belong to the known alkaloids. In the human medicine these substances which seem in a lot of plants play an important role.
Ants are famously for the fact that they can produce alkaloids. "Hence, you were also valid as that spring which delivered the poison of about 190 arrow poison frog species currently" as the expert explains for tropical frogs Walter Hödl of the institute of zoology at the university of Vienna in the press text conversation. The fact that the frogs really eat mites, confirms the scientist. Saporitos research team had caught in traps on the primeval forest ground the mites and had examined. The analyses proved that 80 different alkaloids existed.
The result is very interesting, also believes Oribatida expert Ludwig Beck of the state museum for natural history Karlsruhe during the press text interview. "The alkaloids in the mites can come, actually, only from plants on which these living beings live", believes baker. This is also interesting because the mites eat, primarily, plant leftovers.
The poison of tropical frogs consists of a mixture from up to 800 alkaloids and also matters to medical uses in the person. "All these toxic substances have a meaning for the human medicine, because they are Neurotransmittergifte", believes Hödl. What was absolutely astonishing in Saporitos investigations, however, are 40 up to now unknown alkaloids which the researchers could ascertain in the mites. "Many of these components show very interesting biological activities and, in addition, are structurally unique", co-author John Daly of the Nationwide institute of diabetes and Digestive and Kidney Diseases means studies in Bethesda/Maryland.
It is interesting also that the frogs are concerned by the toxic substances in no manner, because they take up this in very much small quantity. However, for longer periods away they are concentrated in the body of the animals. "The frogs do not change the substances chemically, but they store them in skin glands and deliver them as a secretion", according to Daly.
Name origin:
The origin of all poison use probably lies for hunting purposes not with the plant poisons, but in the skin poisons more indeed, in the amazonischen rain forest of home frogs. Here the connection was specifically discernible between cause and result, finally, in direct body contacts. The Auka do not help themselves to the production of her arrow poison of this animal spring. Although a whole series of tree pit foreman or arrow poison frogs is home in her living space, there is no tip that they could have handled in the past also with these frog poisons. Still should be entered here on the interesting chapter of the tropical frog poisons and her bearers briefly. Toxic skin secretions are spread with Amphibians all over the world. Some South American frog kinds from the row toxic Phyllobates-and Dendrobates-kinds excel everybody remaining in poisonousness. In her majority it concerns with them the very small mostly still garish-brightly coloured animals who do not cross a size of about 5 cm. Their living space are the primeval forest trees, also the primeval forest ground on which they stay with pleasure in the tiny "rainwater ponds" of the epiphytischen bromelias. Their poisons are partly alkaloids from high, partly protein-containing secretions of low poisonousness. They are generated in skin glands and resign with stress and also with light pressure as a milky mucus. The strongest frog poison free of protein is called Batrachotoxin. If even a low track of this poison comes to the bloodstream, the death enters by muscle paralysis and respiratory standstill. Already the amount from five milligrammes Batrachotoxin enough to kill a mouse immediately. The golden poison frog resident in Colombia (Phyllobates terribilis) is certainly most toxic among his colleagues, presumably the most toxic animal generally on the earth. Not free of charge the bang-yellow sometimes also orange or metallic-green mite carries his scientific epithet "terribilis" the awful.
Colombian South American Indians help themselves his in the easiest manner to poison her blowgun arrows: they lead the arrows under gentle pressure about the skin of the living animal. Besides, the frog is preserved unscathed and for repetitions of this procedure. The so treated arrows are usable immediately and could kill a medium-sized dog right away. This direct procedure is not the Huaorani kind. They prefer her method of the Curare-production to the Stone Age pinch of her Colombian brothers. Remains to hope that few left-over Huaorani-families will have opportunity in the ecuadorianischen rain forest still long time to wander with her blowguns and her poisoned arrows from own production on prey by her primeval forest. The chances for the Huaorani stand not very good, in any case. With her selfbrewed poison at the fine blowgun points and with her well-tried survival technologies they have not grown to the penetration of civilisation and technology. What sets everything with them, will have to be copied on the big account of that steadily growing substance loss on which with the primitive races gets lost at the end also bit by bit. On it we can take poison! That material "CURARE" which they discovered once for her hunt as an arrow poison will remain from them. It has come meanwhile long ago into the chemical-pharmaceutical instruments of our medicine and has already helped quite a lot of death-consecrated in the civilised countries. Who of them has thought to the „small, wild people“ to whom we owe the knowledge of this as dangerous as useful poison?
Result:
Poisonousness there or here. Arrow poison frogs are no soft animals and should not be moved needlessly by touches in stress. While working in the terrarium everybody should operate with care and be aware to the rest risk, just if it concerns animals acquired anew. (especially adult animals from questionable spring)
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