Earth hates you and indeed all life

If the Earth were somehow sentient or at least capable of intentional mallace, I'd say that it most certainly would hate life. I'm sure someone will say to me "But Earth is IDEAL for life". Well I'd question that- is it really? Sure, life adapting to the Earth and it's ways have made it as ideal as possible for life on this planet, but that creates the illusion of a most hospitable planet. I'm not saying that Earth is totally unwelcome to life, but I am saying that its not this wonderous piece of perfect that people seem to think it is. In fact, without Algae and in evolution of Chlorophyll/Chloroplasts or, even further, the evolution of Lignen(crucial step in the evolution of plants from algae-like ancesters) the Earth will still be a quite unlivable by most animal life that's to that lovely stable molecule known as Carbon Dioxide, which the Earth spews out wholesale, especially when it was tectonically less stable in antiquity.

Now, onto the point: Why the Earth isn't so fantastic. Well, lets start with the wobble in the Earth's axis, causing seasonality. Seasonality means two things, generally speaking. A winter/summer cycle or a dry/wet cycle. I'm sure anyone reading this has seen all the documentaries of great migrations of Gnu looking for food in the dry season, or amphibians or fish having to go dormant and encase themselves in mud just to survive. Hell, even the mighty Hippopotamus has to deal with concentration in what is left of rivers in the dry season. So, that's a huge pain in the ass...but during the migrations back to the wet feeding grounds, the gnu have to cross outrageously swelling rivers, leaving them prey to drowning and animals that have adapted to take care of them as they struggle (crocs). So we see a recapitulation of the theme I mentioned in the previous chapter: animals, in this case crocodiles, evolving to take advantage of the ass pain that is seasonality. As for the warm/cold cycle, it should be noted that there are animals that have evolved to take advantage of this by huge migrations. These animals are the millions of caribou, but there are also animals that have evolved to take advantge of them, draining up to 1 liter of blood from them PER DAY. These would be dipterans, natures most annoying animals.

Seasonality is a whore, but it creates specialization just to take advantage or survive in these niches. A poster child of this would be polar bears, but many amphibians are a good example of this. If you hyperspecialize, you'll fall prey to an environmental shift, just ask Platybelodon. So seasonality is a harsh mistress- not only does it inconvenience or cause wholesale death, but it creates hyperspecialization which leaves animals vulnerable on the long term to the ever shifting environments on our planet. If you want long term and widespread success, do as many small rodents and birds do- generalize, generalize, generalize. It means you may get outcompeted in one microenvironment, but in the long term you will usually be the winner. When taken to its extremes, ice ages contribute to wholesale killoffs despite what hippies will tell you about it being man and not 60 below fucking zero that killed off many species.

Tectonics is the second ass pain demonstrating that the planet is a real bitch. The end-Permian extinction is a pretty good example of this; pangaea set the stage for the most nasty dieoff the planet has ever seen. Long term tectonic activity can be devastating to entire groups. Once again though, environments that seem exceptionally unhospitable are made their own by some pioneering animals; in this case, Pogonophorans at geothermal vents. They take advantage of these ephemeral habitats, using wide range broadcast spawning to fluke out and move to the next environment. This reminds me of another example of a ephemeral habitat that makes a barren desert of the oceans depths flourish with life- a whale carcass. Once again, animals take advantage of these habitats that are otherwise very, very harsh. In fact, even terrestrial deserts are made their home by Camels and Oryx, even some amphibians can survive in these environments for decades at a time.

Even thinking of things that are ubiquitous in nature that are exploited wholesale by animals is the reactive and potentially deadly molecule known as Oxygen. How life evolved to exploit this is beyond me, especially since it is a waste product to any photosynthesizers. In fact, photosynthesizers make entire environments for other organisms- forests. I could go on forever about how the sheer adaptability of life has made this planet into something that seems really good for life.

One last comment is volatile environments that select for generalization- mountains and low nutrient mountain streams. Lichens, mosses and even forests spring up in these rocky wastelands, which allows for entire ecosystems to flourish. In fact, the largest extant amphibian on the planet lives in high oxygen, low nutrient streams by having a low metabolism and eating anything it can fit in its mouth that looks like a fish.

In conclusion I'll just point out, again, that life actually makes this planet liveable. It was likely extremophiles that first got the ball rolling. I am a little skeptical of the warm tropical water origins of life, though it is reasonable to include this as a hypothesis. I am more in favor of an oxygen rich cold-water origin of life, or an extremophile ocean vent origin for life. It seems that the slow start to life is all the comparison needed to show that this planet really doesn't like life. Once it got started though, it was terraformed quite rapidly and life began exploiting this planet. It should be noted that I'm not comparing this planet to Jupiter, Saturn or even Venus. Those planets would kill almost any life faster than we'd know what hit us. Early Earth and the slow rise of life, as well as the violent tectonic ways of this planet, definately show that this place isn't ideal for life, it just simply works.