Let me introduce you to Bufo marinus, known to many Australians as the cane toad. A government department introduced them to Australia from Hawaii in 1935 in an attempt to control sugar cane beetles. The toads mumbled ‘thank you very much’, had no impact on the cane beetles, and bred prolifically, quickly spreading along the coastal fringe of Queensland. The toads have poison glands on both sides of their neck which produces a toxin more than capable of killing just about every predator they might encounter. That is, lizards, snakes, birds, and toad-eating mammals like quolls and cats. All attempts to eradicate this noxious creature have been unsuccessful and the toad has spread into New South Wales and across the Northern Territory into Western Australia, where the invaders are making their way down the West Australian coast. This fact sheet includes a map showing their current range – and their potential range.
In short, they’re taking over the country, adapting to changed conditions as they move. There is some resistance. A number of bird species have learned to attack the toad’s belly, thus avoiding the poison glands. Some native species are not affected by the toxin, but all in all, the introduction of cane toads into Australia has been devastating. In some respects it can be likened to one other feral, invasive species, which has managed to decimate the whole damn planet.
Planet Earth is well overdue for a mass extinction. We have them here fairly regularly, you know. The five main ones so far are
- End Ordovician, 444 million years ago, 86% of species lost
- Late Devonian, 375 million years ago, 75% of species lost
- End Permian, 251 million years ago, 96% of species lost
- End Triassic, 200 million years ago, 80% of species lost
- Cretaceous-Paleogene, 65 million years ago, 50% of species lost
Everybody knows about the Big One, when the dinosaurs and just about everything else was wiped out in what is generally considered to have been a meteorite impact. The reasons for all the other extinctions weren’t quite so obvious but it comes down to changes in climate (both cooling and warming), seismic activity, changes in the acidity of the ocean, and massive intrusions such as bloody great cosmic boulders dropping out of the sky. The massive extinction at the end of the Permian might also have been caused by an asteroid or comet but no crater has been found. 
It seems that we are living through another mass extinction and the perpetrators of this one are humans, two-legged cane toads of the planet. Everywhere we go we pollute, we squander, we murder each other and far too many of everything else. Try googling ‘extinctions in the past 100 years’ and you’ll get plenty of lists. Here’s just one. American passenger pigeons which existed in their millions, dodos which tasted too good, the iconic thylacine (Tasmanian tiger), Asian lions, English wolves. The world tiger population has plummeted. As recently as 100 years ago one hundred thousand tigers roamed Asia. Now it’s less than four thousand.  What about the many, many invertebrates, birds, small marsupials, sea creatures. And it’s all because of US. Homo ‘sapiens’ – I’m not sure we’re very wise. Otherwise why would we imagine ground tiger penis would give us virility?
While our oceans are becoming more and more polluted and we destroy wild habitat to fuel our obsession with ‘stuff’ which so often ends up in landfill, we hold useless meetings so that far too many delegates can discuss ‘climate change’ and come up with sanctimonious resolutions and unachievable targets that ‘world leaders’ have no intention of even attempting to meet. I’ve made it clear enough on this blog that I don’t think humans are responsible for climate change. That’s dictated by much larger, slower forces, like plate tectonics and the cycles of the sun.
But we’re sure as hell responsible for plastic and other items of the throw-away mentality encouraged by the retail corporations which control too much of our society. I’d much prefer discussions about how to clean up the oceans, stop overfishing, and prevent idiots from cutting down and/or burning rain forest. Those things we can change.
About here I’ll make my own prediction based on not a single computer model. Even so, iIt’s probably almost as accurate as those computer-generated predictions about sea level rises.
I think we’re overdue for a catastrophic mass extinction of the dominant destructive infestation on this world. Gaia will awaken and scratch her itching skin. The San Andreas Fault hasn’t slipped in a while. The super volcano bubbling quietly under Yellowstone National Park could erupt at any time. Vesuvius is simmering. Indonesia’s volcanoes are skittish. Just the other day earthquakes shook New Caledonia and Norfolk Island in the Pacific. Volcanic activity can have immense global effects. Here’s what happened when Krakatoa blew its top in 1883.
“In the year following the 1883 Krakatoa eruption, average Northern Hemisphere summer temperatures fell by as much as 1.2 °C (2.2 °F). Weather patterns continued to be chaotic for years, and temperatures did not return to normal until 1888. The record rainfall that hit Southern California during the “water year” from July 1883 to June 1884 – Los Angeles received 38.18 inches (969.8 mm) and San Diego 25.97 inches (659.6 mm) – has been attributed to the Krakatoa eruption. There was no El Niño during that period as is normal when heavy rain occurs in Southern California, but many scientists doubt that there was a causal relationship.
The Krakatoa eruption injected an unusually large amount of sulfur dioxide (SO2) gas high into the stratosphere, which was subsequently transported by high-level winds all over the planet. This led to a global increase in sulfuric acid (H2SO4) concentration in high-level cirrus clouds. The resulting increase in cloud reflectivity (or albedo) reflected more incoming light from the sun than usual, and cooled the entire planet until the suspended sulfur fell to the ground as acid precipitation.” 
And all it needs to decimate human populations is a virus. It happened once before around 1350. Somewhere between a quarter and a half of the population in the known world was wiped out. It took centuries for the population to recover. More recently, the influenza that spread through the world after the first world war killed more people than had died in the war itself. In today’s world with so much travel on aircraft, an infection could spread all over the planet in days.
Add some catastrophic fires, cyclones, earthquakes, and eruptions, and Gaia could rid itself of this pesky species like a dog being given tick control.
Frankly, it’s all we deserve.