Original sentence: - John Ward's Nature & Society paper says: "Paradoxically, we look likely to be one of the species with the shortest evolutionary appearance if we continue our current suicidal behaviour.Alternatively, several generations of designer babies could lead to a species unable to inter-procreate, accidentally producing true (rather than pseudo) extinction.In favour of human extinction: Voluntary Human Extinction Movement homepage, "May we live long and die out".In the very long term the ultimate threat to humanity may be entropy: the postulated heat death of the universe predicted by the second law of thermodynamics.Is there a real risk of human extinction.It often proved fatal.Most people consider that the extinction of the entire species is an infinitely worse fate than the death of an individual.Perceived long-term threats to humanity include the destruction of Earth in about five billion years when the sun becomes a red giant, and possible changes in Sol's radiated spectrum as it undergoes stellar evolution before then.The former NASA consultant David Brin's lengthy rebuttal to SETI enthusiast's optimism about alien intentions concludes: "The worst mistake of first contact, made throughout history by individuals on both sides of every new encounter, has been the unfortunate habit of making assumptions.The minority view, in favour of human extinction (as advanced by groups like The Voluntary Human Extinction Movement) is that humanity is inherently destructive to this and any future ecosystem, and that the needs of the biosphere should outweigh human's desire for "immortality".catastrophic climate change, including the results of global warming, or super-caldera.invasion by militarily superior aliens: often considered to be a purely entertaining scenario, this speculation has been advanced as a (very slim) possibility by professional cosmologists.loss of a breathable atmosphere - through deforestation, ozone layer destruction, or toxic industrial pollution.supernova in our part of the galaxy (advanced as a cosmic "sterilizer" to explain the Fermi paradox by some astronomers)
Edited sentence: Humans consider that the extinction of the entire species is an infinitely worse fate than the death of an individual.Perceived long-term threats to humanity include the destruction of Earth in about five billion years when the sun becomes a red giant, and the postulated heat death of the universe predicted by the second law of thermodynamics.catastrophic climate change, including the results of global warming.invasion by militarily superior aliens