INSERT INVASIVE SPECIES HERE

Man… we sure know how to bugger things up. We often mean well, we just equally often overlook little things that turn out to be not so little after all. Take the case of the “Australian” cane toad. It was introduced in 1935 to combat a beetle population that was decimating the sugar cane crop. It worked well in Hawaii and Philippines, what could possibly go wrong? What indeed. The cane toad turned out to be ineffective in the beetle battle, but was quite an accomplished breeder (its range now covers 20% of Australia), and has become a bane to many aboriginal species, including goannas, snakes, marsupials, and even freshwater crocodiles. There are no real predators of the cane toad in Australia, mainly because it is so poisonous (crocodiles have even been found dead with cane toads locked in their jaws), so it continues to propagate, proliferate, and choke out native species of fauna. What’s Australian for “whoops”?

In the 1800’s, the Common (European) Carp was introduced in the United States (and later in Canada), to be used as a food source. I guess it seemed like a good idea at the time, but I haven’t seen carp on the menu much lately, and experts have since found that it too
can be quite an invasive species. The bottom feeding carp can drastically alter its environment, rummaging through the sediment and uprooting vegetation, affecting native fish and water fowl populations. The Common Carp is just one of many introduced invasive
species in the US today, carrying an estimated economic impact of over $200 billion each year, not to mention the snuffing out of many indigenous species.

Those are examples of intended, albeit ignorant, introduced invasive species, but what about some (comparatively) inadvertent, or should I say indirect, ways we affect the Natural World? In Britain (originally, but North America is also guilty), study after study has
shown that rivers polluted with “anti-androgens,” in the form of pharmaceuticals, cleaning chemicals, and pesticides, are causing 1 in 3 male fish to develop feminine reproductive characteristics. This “feminizing” of male fish is inhibiting their ability to reproduce and is a major contributing factor to the decline of some species. So now we’re giving animals sex changes.

But wait, now we ARE giving animals sex changes. Back in the US, scientists took note of this fish feminization phenomenon and decided to put it to use. Juan Gutierrez, a bio-mathematician at Florida State University, has devised a way (in the form of a mathematical model) to fight carp populations using “Trojan chromosomes”. Essentially, and I’m paraphrasing quite loosely here, by exposing fish to their sexual counterpart’s hormones, scientists can create male-seeming fish with female chromosomes, and vice versa. A female fish with YY chromosomes will only be able to have male offspring, so scientists need merely to keep introducing these “intersex” fish into wild populations over the course of a decade or few, creating a mono-gendered local population, et voila, the invasive species dies out. Now that’s learning from your mistakes.

Speaking of learning from mistakes, Australian authorities, still embroiled in their cane toad conundrum, have come up with a less invasive way to introduce a species that will, with any luck, halt their previously introduced species from doing any more damage to
aboriginal species (incidentally, does anybody know if they ever solved that beetle problem?). In marches the Meat Ant. This particularly aggressive ant, a colony of which can reduce an animal carcass to bones in a matter of weeks, has been found by researchers to be extremely effective against the cane toad. They are both diurnal (native frog species are predominantly nocturnal), and the cane toad just happens to prefer breeding in the same types of areas where meat ants like to forage. Add that to the fact that a cane toad’s short shin bones make it too slow to outrun a marauding meat ant horde, and you have yourself a cane toad killing machine. Perhaps the best part of this solution though, is that in this case authorities need not introduce a new species to Australia. They need
only relocate one. What could possibly go wrong?

This all got me (and I hope you) thinking, what is the most invasive species of all? Well, with all our meddling in Mother Nature’s affairs, we are of course. On a grand scale no matter where we go we can’t help but alter the environment to the detriment of the majority of the local inhabitants, practically making us the definition of “invasive species”, which leads me to the obvious next question; Who put people here?

And what are they going to use to get rid of us..?

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