|MadSci Network: General Biology|
Hello Gareth, The "easy" answer to your question is that you are absolutely right. We (humans) tend to filter our discoveries based on our 'narrow' but accepted views about life. We are looking for "things" that we associate with life here on the Earth. "Things" can mean chemicals (e.g., amino acids or complex organic molecules) or active or fossilized cellular structures. A very limited viewpoint dominates the question of extraterrestrial life; i.e., we believe that things should be similar to our familiar Earth. Examples include the belief that an oxidizing atmosphere and water and complex carbon backbone molecules are required to support and define "life". You have posed a very interesting and controversial question for which there is no fully satisfying answer. These questions require much more study by persons willing to see beyond the limitations of our present chemical and biological knowledge. This research costs money. An unfortunate aspect of research funding is that it is easier to get moneys for projects that support the currently accepted viewpoints. Opinions expressed above are mine and may not agree with those of my employer. John Haberman
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