#726 Why does Australia have so many dangerous animals?

Why does Australia have so many dangerous animals? It actually doesn’t have as many dangerous animals as people think and there are other countries that have more. However, for a single country it does have a large number of dangerous animals, partly because of its location, its size, and because of evolution. Let’s try and unpack this.

A lot of lists show that Australia has almost all of the world’s most deadly creatures. This is not true. Australia has 66 venomous species and it is beaten by Brazil with 79 and Mexico has 80. Some of the species of venomous animal that live in Australia are more venomous than other countries, but Australia doesn’t have a monopoly on dangerous animals. However, we are talking about deadly creatures and not just venomous creatures, so we need to look at animals like crocodiles as well. Australia does have a lot of crocodiles, but they are located in the north of the country. And Australia doesn’t have the largest concentration of crocodiles by any means. There are more crocodiles in most of the South American countries, Central Africa, Indonesia, the Philippines, and even the USA. Australia does have a large number of sharks, but it is not number one. The USA is the country that has the most shark attacks every year and Australia comes in at number two. Although, because of the culture of going to the beach, swimming, and surfing, a higher number of shark attacks doesn’t necessarily mean a higher number of sharks.

Australia may have a large number of dangerous animals, but the danger of these animals is relative. A snake may be able to kill someone in a few hours with its venom, but if it lives where there are no people, or if it is very unlikely to attack a person, is it still dangerous? Because of Australia’s sheer size, people tend not to live where the dangerous animals are and the likelihood of being bitten by something is actually quite low. Compare that with Indonesia, a more population dense country, and a smaller number of dangerous animals cause a greater number of injuries or deaths. Australia is also helped because of its first-class medical system and copious anti-venoms.

The three types of animal that are most commonly brought up on the list of most dangerous animals in Australia are spiders, snakes, and jellyfish. The box jellyfish is the most venomous jellyfish in the world. It has 15 long tentacles and each tentacle has thousands of stinging cells. They can kill a person, but if treatment is available the stings are not always fatal. The box jellyfish is listed as one of Australia’s most dangerous creatures, but they are not unique to Australia. They live in warm seas and they can be found in the Gulf of Mexico, around Africa, and in most of Southern Asia. Again, the fact that they seem to be associated with Australia could be because more people are swimming in the seas.

Spiders and snakes are a different issue because they are not brought in by warm seas. Australia has 140 different species of snakes. 100 of those species are venomous and 12 are dangerously so. There are 10,000 species of spider, and only a few of them are venomous. The spiders that are venomous do appear to have a very strong venom, but nobody seems to know why they need such a powerful venom.

All of the venomous spiders and snakes that live in Australia have evolved there because the Australian landmass broke away from all the other continents about 750 million years ago. It has been isolated for so long (until the British brought invading species) that the animals there have evolved from the original animals. The likelihood is that when the landmass broke away, there were only venomous snakes and spiders on it. Over millions of years, they have evolved into a mix of very venomous, mildly venomous, and not venomous snakes and spiders. This would explain why there is a large number of venomous ones.

However, it is worth repeating that a lot of the danger seems to be hyped up. There hasn’t been a death from a spider bite in Australia since 1979. There are two or three deaths from snake bites every year, but they are almost all from people who didn’t realize they had been bitten and who didn’t seek medical help. Australia does have a lot of dangerous animals, but so do a lot of other countries, and Australia’s medical service, anti-venoms, and sheer size means that the dangerous animals are probably not as dangerous as we think. And this is what I learned today.

Photo by Jonas Schallenberg: https://www.pexels.com/photo/uluru-rock-formation-in-central-australia-6610368/

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