A new theory suggests that the reason we did not find alien life in is the Universe yet is because it just went extinct, not because life has never evolved elsewhere. There are many planets displaying supporting life conditions but astrobiologists suggest alien life forms just didn't survive, rather than never managed to emerge.
The new study performed by scientists from the Australian National University was presented press release and published in the journal Astrobiology. According the research team, it could be only a small window for life to evolve and for the life-forms to modify their environment.
This narrow timeframe ranges between 500 million and one billion years. During this time, in case that the evolving beings cannot stabilize their planetary conditions, it is highly possible that their home will become uninhabitable.
Lead author Aditya Chopra declared in the press release that the universe might contain many habitable planets. Howeve, it was noted that early life rarely evolves fast enough to survive because it is too fragile.
Life may not stand a chance because temperatures could be too high in the first millions years of a planet with the potential for life and the universe will be bombarding it with too much debris. Even of conditions for the emergence of life-forms might appear if impact rates decline and temperatures cool over time; if the new creatures miss their billion-year window, they might die when liquid water freezes or boils.
According to The Christian Science Monitor, the authors of the study have dubbed their hypothesis the "Gaian Bottleneck". Their theory is suggesting that rocky planets need to be inhabited in order to remain habitable, while extinction on wet rocky planets is happening for most life that has ever emerged.
The Gaian Bottleneck model is predicting that the majority of fossils humans could ever find in the universe might be not from multicelluar species but from extinct microbial life, according to the website Space.com.
