A brief excerpt:
Yet no matter how palatable the methods and outcomes are, it seems to me that changes to humans will be inevitable if we ever want to go beyond the orbit of Pluto within one lifetime. Successful implementation of transhumanist techniques will help overcome the immense distances and inhospitable conditions of the journey. The undertaking will also bring about something that naysayers tend to dread as a danger: speciation. Any significant changes to human physiology (whether genetic or epigenetic) will change the thought/emotion processes of those altered, which will in turn modify their cultural responses, including mating preferences and kinship patterns.
Andreadis' proposal reminds me of speculation that the so-called "Grays" that play such a pivotal role in the modern UFO mythos are in fact genetically engineered for space travel. With its small, streamlined frame, the anatomy of a prototypical Gray might be ideal for long space voyages; if we chose to send a "generation ark" to a nearby star, we might very well design our astronauts along similar lines.
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