Alien Scientist 26: The Conquest Of Life On Earth
Stephen Marshall, a former resident of Tsukuba, has been writing Alien Scientist articles for the Alien Times since 2001. Even though he no longer lives in Tsukuba, he is still a regular contributor to the magazine. Here is his latest intergalactic report.
In his book Nature: An Economic History, Geerat Vermeij applies economic concepts – such as competition for resources, functional specialisation and economies of scale – to the natural world. The book has been described as ‘Economics, as if written by intelligent aliens’, perhaps because the human world is treated impartially alongside the rest of the ecosystem. (In fact, due to the authoritative treatment of marine snails, the book might be especially appreciated by intelligent alien molluscan Earthologists).
In generalising across widely differing life-forms, the book, as well as reinforcing the idea that homo sapiens is ‘just another animal’, invites one to wonder if the phenomena described might hold true for life on other worlds. In other words, if on Earth it was possible that a combination of originally inorganic substances could somehow organise themselves into a system of living things – that eat, compete or otherwise interact with each other in the whole runaway roadshow we call life – then why should the same not happen elsewhere in the universe?
After all, Earth must originally have seemed a rather hot, toxic place for life to start. But eventually, somehow, life got a foothold, expanded to occupy sea, land and the air, and went on to conquer most of the Earth’s surface, occupying almost every conceivable space and crevice on what was once a naked mineral satellite. As life developed, the planet grew itself its own ecosystem. So what we call our environment – forests, marshes and seashores – is significantly organic: not just a physical stage-set framing the action, but part of the action itself.
Life’s conquest of Earth has been so successful because it has found ways of adapting to diverse circumstances. Species have morphed, mutated and experimented with themselves until they would eventually fit a diversity of niches all over the planet. Where light has been abundant, we have evolved eyes. Where the atmosphere has been right, we have evolved wings. Where enemies abound, we have evolved camouflages and poisons. In all cases, these features have evolved independently many times and in many places. If this is so on Earth, there seems no reason why it should not happen elsewhere. The universe should be teeming with eyes and wings, mimics and stings.
All this evolutionary innovation is spurred by competition. Everywhere individuals, species and businesses are trying to out-compete each other. In open competition, the strong will take over, absorb or eat the weak. Successful species unleashed into a new environment may wipe out the native species. But strength and success are always relative, and dependent on the context. Sometimes it is the big beasts that are wiped out, while the smaller creatures live on. Big companies often swallow smaller ones; but sometimes they crash spectacularly, and the little ones pick over their remains.
If the dinosaurs had not been wiped out, perhaps the first Earthlings on the moon would have had scaly tails and toothy beaks. Instead, the mammals prevailed and flourished; now humans are seemingly in charge of much of the planet, with ambitions for colonising others. But if a more successful life form comes along – an intelligent mollusc, perhaps, or a disarmingly friendly computer virus – then the humans may yet be overtaken. The history of the next millennium could yet be typed by geeks with tentacles.
In fact, there seem to be some typical patterns in the conquests of life. Species that evolve in large abundant continental areas tend to have a competitive advantage over species native to smaller, more sparsely resourced areas. So when continental species are introduced to islands or other relatively isolated habitats, they often quickly take over. This biological fitness for conquest is perhaps echoed in the human world of technological supremacy. History shows that the peoples with superior technology – whatever their culture or morals – tend to prevail over those with simpler kit.
This does not make comfortable reading for Earthlings in the face of an alien invasion. For a start, the chances are that the aliens – in order to have made it here – will have the better technology. And since Earth so far has been completely isolated from any extraterrestrial competition – from any teeming galactic ‘continents’ of competitive civilisations – then the chances are that the aliens will be better at taking over new habitats than we are at defending them.
In this case, we should hope that the aliens are not interested in Earth as a new home, or as a biotic filling station on some inter-galactic highway. In the circumstances, our military technology may be useless. Instead, we might have to hope that our alien visitors are Earthophiles, interested in ecotourism rather than exploitation. In which case, a book about our planet written as if by – or for – intelligent aliens might be our best hope.