My personal suspicion is that intelligent life requires a wide variety of complex cellular machinery, which requires multiple global extinction-level events to weed out more highly specialized species utilizing more efficient but less adaptable survival mechanisms; each extinction-level event, in this suspicion, would raise the potential complexity of the environment, until intelligence becomes more advantageous than expensive. However, there’d have to be spacing between global extinction events, in order to permit a recovery period in which that complexity can actually arise. Any planet which experiences multiple global extinction events is likely to experience more, however, so the conditions which give rise to intelligent life would usually result in its ultimate destruction.
This hypothesis is interesting and not one I’ve seen at all before. It seems to run partially afoul of the same problem that many small early filters would run into- one would be more likely to find civilizations around red dwarfs. Is there a way around that?
The low luminosity of red dwarf stars makes them unsuitable for an earth-like environment, I believe. I don’t have enough information to comment on a non-earthlike environment supporting life.
The stability of red dwarves, however, could work as a filter in itself, limiting the number of global extinction events.
The low luminosity of red dwarf stars makes them unsuitable for an earth-like environment, I believe. I don’t have enough information to comment on a non-earthlike environment supporting life.
Red dwarfs have a smaller habitable zone than our sun, but if you have a planet close enough to a red dwarf this isn’t an issue. This is exactly the problem: if there are some set of not so likely series of events that will occur, then one expects to find civilizations around red dwarfs. If one expects that’s not the case then the big habitable zones on somewhat bigger stars make one more likely to expect a civilization around those stars. We see the second.
The stability of red dwarves, however, could work as a filter in itself, limiting the number of global extinction events.
Possibly, but I don’t think that any of the major extinction events in Earth history are generally attributed to large solar flares or coronal mass ejections or the like. So it seems like asteroids and geological considerations are more than enough to provide extinction events.
Red dwarfs have a smaller habitable zone than our sun, but if you have a planet close enough to a red dwarf this isn’t an issue. This is exactly the problem: if there are some set of not so likely series of events that will occur, then one expects to find civilizations around red dwarfs. If one expects that’s not the case then the big habitable zones on somewhat bigger stars make one more likely to expect a civilization around those stars. We see the second.
AFAIK planets close enough to a Red Dwarf to get enough lumosity stop being earth-like due to other effects (likely rotational periods, tidal forces).
My personal suspicion is that intelligent life requires a wide variety of complex cellular machinery, which requires multiple global extinction-level events to weed out more highly specialized species utilizing more efficient but less adaptable survival mechanisms; each extinction-level event, in this suspicion, would raise the potential complexity of the environment, until intelligence becomes more advantageous than expensive. However, there’d have to be spacing between global extinction events, in order to permit a recovery period in which that complexity can actually arise. Any planet which experiences multiple global extinction events is likely to experience more, however, so the conditions which give rise to intelligent life would usually result in its ultimate destruction.
No hard evidence, granted. Just suspicion.
This hypothesis is interesting and not one I’ve seen at all before. It seems to run partially afoul of the same problem that many small early filters would run into- one would be more likely to find civilizations around red dwarfs. Is there a way around that?
The low luminosity of red dwarf stars makes them unsuitable for an earth-like environment, I believe. I don’t have enough information to comment on a non-earthlike environment supporting life.
The stability of red dwarves, however, could work as a filter in itself, limiting the number of global extinction events.
Red dwarfs have a smaller habitable zone than our sun, but if you have a planet close enough to a red dwarf this isn’t an issue. This is exactly the problem: if there are some set of not so likely series of events that will occur, then one expects to find civilizations around red dwarfs. If one expects that’s not the case then the big habitable zones on somewhat bigger stars make one more likely to expect a civilization around those stars. We see the second.
Possibly, but I don’t think that any of the major extinction events in Earth history are generally attributed to large solar flares or coronal mass ejections or the like. So it seems like asteroids and geological considerations are more than enough to provide extinction events.
AFAIK planets close enough to a Red Dwarf to get enough lumosity stop being earth-like due to other effects (likely rotational periods, tidal forces).
The situation is a bit more complicated. Wikipedia has a good summary. There’s also been more recent work which suggests that the outer end of the habitable zone around red dwarfs may be larger than than earlier estimates. See my earlier comments here on this subject.