© Unknown
There seems to be a tendency to set evolution and catastrophism as opposite ways of thinking. That's a big misunderstanding. As if Darwin or the concept of evolution would need some defending against some mystical, religious or supernatural concepts, there is coined the term punctuated evolution. I see no need for any such term. Evolution as a theory in the form as Darwin put it, needs refinements in the same way as Einstein refined the theories of Newton. Nothing more, nothing less.

So what has changed since Darwin to warrant this discussion or, more specifically, what has to be added or refined? In short, the paraphrase of the "survival of the fittest" must be enlarged to the "survival of the fittest of the luckiest". Evolution as such has no ultimate goal. It has only temporary goals, as long as we see the universe as a changing place.

Taking as an example our home planet, the Earth, it seemed for billions of years, from some 3.8 billion of years ago (when the bombardment in the Solar System lowered to its nowaday level) to some 800 million years ago, a suitable place for micro-organisms to fill every niche available to them. At some places there most probably was some cooperation between some micro-organisms that was nearly or exactly like multi-cellular life.

That could be the case even today if not something had happened 800 million years ago. The surface of Venus heated to the point of melting, Earth was all covered in ice and snow, Mars had its atmosphere, and probably also oceans, blasted into space, thereby killing probably all life that might have been there at the time, as also happened on Venus. Whatever happened, a nearby supernova, a nearby gamma burst, a superflare from the Sun, you can add this list, is anybody's guess.

Then about 600 million years ago the Solar system recovered. Not however to its previous stage. Mars and Venus had lost their biosphere, but the Earth's biosphere either partially survived under the ice- and snowcover or at least was reborn very quickly. Whatever happened, the evolution continued on Earth as before, but now under greatly changed circumstances. The Precambrian Ediacara-fauna is a most beautiful example of its force. The Earth has never since seen so great a biodiversity. The changed environment was suitable for multicellular life, there was a clear advantage for different functions for different organs to act as a whole organism.

When the tens of millions of years went on, the recovering Earth changed and/or the populations grew until either the changed environment was not suitable for all Ediacara fauna or the Earth became too small to such a large biodiversity. The fittiest of the luckiest, those that were on the right place at the right moment survived and the Cambrian world was born. It would be here today, somewhat changed, but principally as it was half a billion years ago, unless something unusual again happened. Whatever it was, it wiped 96% of the genera of Earth's bioshere into oblivion 250 million years ago.

It looks like the Earth changed to a tropical place without ice anywhere, not even on the poles. With all the conditions favorable for life, there grew on Earth a fauna that was as big as the Earth's gravitation allowed animals and plants to be. It was the era of dinosaurs and the great fern trees. Evolution has no direction, so the fauna changed only when circumstances changed, for example because of the movements of the tectonic plates, but the changes were statistically random. For some 170 million years dinosaurs lived here without any indication of any change in intelligence or any other essentials. They would still be here today, essentially unchanged, unless a medium-size, 10-km asteroid would not have hit the Earth at a place now called Yukatan 65 million years ago. Without this blast we wouldn't most probable be here.

After this earthly big bang Earth has been a battle ground between micro-organisms, insects and mammals and some more minor groups. We know of no trend in the evolution of micro-organism and insects, only random adaptations to changing environments. But one change has been so huge and dominating that this trend-like change has demanded trend-like change from mammals for them to adapt.

The last 50 million years the Earth has continually cooled disregarding some standstills and minor warmings that all have been temporary. The last phase in this climatic deterioration has been the oscillating temperature that began as a minor series of events about 3 million years ago and changed to the famous 100,000 ice age oscillation some 800,000 years ago. Even the highest temperatures (socalled interglacials) have been colder than any phase on Earth during the last 65 million years, and probably over 200 million years.

Be the reason the continental drift (a continent on the southern pole), the rise of Tibetan plateau, something inside the Sun, a change in our cosmic environment in the galaxy or something else or all or part of these, the fact is that intelligence became a new advantage for survival in this cooling environment. Although there occurred a cessation, even a slight direction change some million years after the great impact events 35 million years ago, which led to the extinction of primates in the northern continents, hominoid diversification began in Africa 24 million years ago (at Oligocene/Miocene boundary). But it was "only" a great increase in biodiversity that lead - besides other changes - to a fauna of very different primates.

When the cooling began anew 14 million years ago, there appear the first hominoids in Africa that are generally called as "advanced". When chimpanzees left the branch that led to men about 4.5 million years ago, when Australopithecines diversified from Homo about 3 million years ago and lastly when the Aorounga impact in Tsad 800,000 thousand years ago (on a much older crater) separated the European and Asian Homo from the Southern African Homo, there was room for an intelligent niche and gene pool that through small mutations was ready to take this niche. And through the mitochondrial Eve and Out-of-Africa behavior this genus, Homo sapiens, was ready to go to the conquest of the Earth. Chimpanzees lost this "opportunity" and, so it seems, have not much changed during the last million years.

Evolution has many faces.