Exogenesis

Marconomics takes the view that Exogenesis *Must* be the default assumption of evolutionary science. The analogy of an island is useful to me as to why this should be so. We do not consider the bacteria, insects, plants etc. on that island to have evolved separately from the primordial ooze. Our base assumption is that living creatures from elsewhere somehow landed on the island and through further evolution, populated vacant niches as best they could. Further encroachments from other areas may have upset the balance but allowed for more competition, genetic diversity, and more effective filling of all the niches. Geogenesis requires a lot to happen in a relatively short time frame in order for life to arise. It doesn't just rest on whether this is possible or not. It is possible that land-dwelling higher creatures on an an island evolved from bacteria residing on the island, but it happens in such a short time that the possibility never gets the chance because of the easy feasibility of the spread of creatures already existent is so much quicker and matches the observed timing. The more obviously appropriate environment for life to have evolved is in a cluster of stars and planets in the early stages of the Galaxy. Say in a region of space with hundreds of stars of different sizes with an average distance between stars of approx 100 Astronomical Units. Amongst and orbiting these would be tens of thousands of planets, with frequent collisions sending stuff from one planet into space to land on another planet within 100,000 years. This is a perfect environment for life to both start in a variety of different guises, and for those guises to both compete and to spread to other planets in the cluster. Types of life that could survive inter-planetary migration of this kind would have distinct advantages, and the only kind of life you would end up with amongst this cluster would be of a type that was compatible with inter-planetary migration and adaptation to any sorts of environments within that cluster. The life would tend not to lose this ability to spread itself, no matter how much evolution happened in the meantime, much as life on Earth never loses the ability to spread itself to proximal environments. In the solar system, the obvious proximal source of DNA is the star systems which exploded forming the dust and gases which the solar system was formed from. The difficulties of inter-system spread of DNA is dwarfed by the difficulties of it happening quickly on any one particular planet.