QUESTION: Abiogenesis – What is directed panspermia?
Directed panspermia is an attempt to evade some of the difficulties associated with the concept of abiogenesis. Panspermia theories argue that life began elsewhere in the universe and was subsequently seeded on earth. Some proponents of panspermia hold that life rode on meteorites travelling through space which eventually landed on earth and allowed the Darwinian mechanism to take over. A major problem with this suggestion is the sheer improbability that any life form could survive the radiation and extreme temperatures found in space.
Other proponents of panspermia, such as the co-discoverer of the double helix structure of DNA, Francis Crick, suggest that intelligent aliens visited earth and seeded it with the first life form. The willingness of many scientists to resort to the hypothesis of aliens does not say much for their prospects of finding a feasible naturalistic model for the origin of life. The main problem with panspermia theories is that they only explain how life initially got to earth -- they say nothing about the actual origin of life. All such theories merely attempt to shift the problem of the emergence of life to another location.