MOST DANGEROUS ANIMAL IS A FROG
by Whit Gibbons
April 20, 2008
dart frog of South America, scientific name Phyllobates terribilis,
is arguably the most dangerous animal in the world. To a laboratory mouse
the frog's skin secretions are more than 400 times as toxic as the venom
of a king cobra. Another dangerous animal, the funnel-web spider from
Sydney, Australia, has venom more toxic than that of an eastern diamondback
rattlesnake. Drop for drop, the funnel-web is about five times as venomous
as a black widow spider.
The comparative toxicity of 30 of the world's most toxic animals are given
in a table in the book "Venomous Animals of the World" (2007,
Johns Hopkins University Press) by Steve Backshall. Based on laboratory
experiments with mice, the lethal dose measurements are not perfect mimics
of how humans would respond, but they are certainly close enough for practical
purposes. Whether a deathstalker scorpion of North Africa is 25 or 78
times more toxic than an African gaboon viper won't much matter if you
get bitten by one of them. In either case, you could be in trouble.
is full of information about and color photographs of the world's most
toxic animals. Some are "venomous," meaning they have venom
glands and inject the toxin into their victims. Others are "poisonous"
in that their bodies or skin secretions are toxic if eaten or otherwise
absorbed. The venomous species include scorpions, centipedes, spiders,
and jellyfish. Poisonous ones include millipedes that produce cyanide,
fire salamanders and California newts with toxic skin secretions, and
blister beetles that secrete a burning chemical from their leg joints.
funnel-web spider is credited with being the world's most dangerous spider.
Although both sexes have venom and will bite, the male is smaller but
more dangerous. Interestingly, the venom of male funnel-webs is more virulent
to humans and other primates than to mice or dogs, which means that they
are even more dangerous to us than some laboratory tests would indicate.
Before an antivenin was developed in 1981, at least a dozen deaths had
been documented from funnel-web spider bites. To develop the antivenin,
venom is extracted from spiders and injected into beagles, which build
up an immunity to the spider venom. The antibodies generated by the dogs
are the foundation for the antivenin. Apparently the development of an
antidote that neutralizes the spider venom in a bite victim has greatly
reduced the chance of fatality from the bites.
photography is outstanding, in part because many toxic animals are brightly
colored. Some of the photographs include the author himself in situations
reminiscent of Steve Irwin, the Crocodile Hunter. In one he is confronting
a Mozambique spitting cobra that he says "let rip with a jet of venom,
which drenched the goggles protecting my eyes." In another he is
holding a brightly colored red, yellow, and black snake "during a
tropical downpour," while he is "frantically assessing the colour
bands to . . . figure out whether it is a deadly coral snake or a harmless
false coral." Backshall is also shown in an underwater scene where
he is reaching his hand toward the mouth of a gigantic stingray. He notes
that stingrays "generally make excellent swimming partners. I fed
this one for nearly an hour and it behaved like a large, friendly dog."
section of the book discusses some of the environmental threats faced
by the featured species of animals. The author notes that unrestrained
human population growth, which has now given us more than 6 billion humans,
is leading to the decline of wildlife on a worldwide scale. Animals in
oceans, forests, and even deserts are under siege from human habitat destruction
and other assaults.
Animals of the World" sports stunning color photographs of some of
the most toxic animals in the world, such as the deadly poison dart frogs
with their brilliant reds, yellows, greens, and blues. A first step in
any conservation effort is to develop an awareness of and appreciation
for all wild animals and plants, even those that protect themselves by
defenses that can be lethal to us. This book does just that.
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