I was reading an article about the possibility of extra-terrestrial life, and it occurred to me that a possible reason that we haven’t found any could be that if all matter was created at roughly the same time (after the Big Bang), then presumably solar systems and planets were formed in the same timespan, and if evolution takes the same amount of time as our evolution has taken, then extra-terrestrials (if they exist) would be in the same state of development as us, and therefore not yet able to contact us.
I appreciate there are an awful lot of crucial ‘ifs’ in the above postulation. Given that (or not, as the case may be), could the above be right?
Given all your “ifs” then your reasoning **could **be right.
However, stars and planets have been forming all along (we even see some starting up now in some nebulae) and there is no reason to presume that it takes four and a half billion years for one species to exploit the tool-using communicator niche. Also, when we are talking about billions of years, a few thousand years of civilized development is effectively simultaneous, so even if all species are at the “same level of development” some should be millennia ahead, technologically and some millennia behind.
Right there is a problem, evolution is dependent on random events. There even seems to be some indication that simple life started and “dead-ended” several times on Earth, before it took off.
If a chance meteor hadn’t wiped out the dinosaurs perhaps, mammals wouldn’t have been able to take over. Perhaps they would’ve anyway, see the problem?
And life contacting us depends on similar intellegence not advance intellegence. For instance, dolphins seem to communicate just fine with other dolphins, but they don’t communicate so well with humans.
Same with other animals. Let’s say there is a planet full of fish. Well the fish will continue to evolve, but they will get better at being FISH, they won’t necessarily evolve into anything able to communicate with us.
Most people don’t deny there is life elsewhere, so much as say we won’t (or haven’t yet) made contact with such life
That is true, but since further generations will have more heavy elements, the chemical composition necessary for life may not come around until the 4th generation. In fact, further generations may have too many heavy elements for life.
Of course, there is no saying that a 4th generation star couldn’t have been born a billion years ago, so the point is moot w/ respect to the OP.
I don’t have a cite, but I’ve heard on documentaries that there have been several ‘great extinctions’ on Earth. The KT extinction is just the one that is common knowledge. Earlier extinctions were largely when life was just getting a toe-hold, and the life-building machine went back to square one, so to speak.
Re: The OP. It’s also possible that we are the first species in the universe to reach the level we have. We could be the suspected extra-‘terrestrial’ (for want of a better word) civilisation!
I don’t know about “several” or “life,” but there was a news report a few months ago about fossils of multi-cellular life that were a few hundred million years older that the ones we already knew about. I think the assumption was that that was a dead end for one reason or another, and it left no descendants for whatever reason (climate, catastrophe, etc.).
Sure, but those early orbs mostly suffered from low metallicity. It’s tough for a star system to have planets when all its got to work with is hydrogen and helium.
Trouble is, that’s give or take a few hundred million years, which is a long time in terms of the lifetime of a technological civilization.
As far as anyone knows, there’s no particular reason the genus homo started its trip up the sentience ladder 2.5 million years ago, as opposed to some other big ape, say 10 million years ago.
Civilization would look a lot different today with that minor tweak to the evolutionary sequence.
The estimated age of the universe is around 13 billion years…with Earth only at 4.5 billion. Where other life does exist, I doubt they are even close to the same timeline as us on Earth. That is assuming that they evolve at the same rate.
I don’t doubt that there is another blue planet out there somewhere. In fact there are probably several. If that’s the case, then life outside our solar system is a possibility. It’s also entirely possible that lifeforms have thrived elsewhere and disappeared in the billions of years between the big bang and the birth of our solar system. Time is a weird dimension that needs to be considered.
Perhaps, but, why would you suppose that we are more “highly” evolved than other creatures on the earth? Just because we have written language and use tools?
One thing that I think factors into this conversation, that I’ve never heard anyone say, is that we live on a planet teeming with life, and yet, we can not really communicate in any “intelligent” way with any other species on Earth. Why is there no other species on Earth that has evolved in our “direction”?
I think there are likely to be many planets teeming with life, but, not “intelligent” life that resembles ourselves.
Out of all solutions to the Fermi paradox (besides that we are alone…which I suspect could be the solution though it is unpopular) this is the most appealing. Maybe we essentially are ‘the first’.
This may seem strange but maybe the earlier universe was not conducive to life…the lack of metals as another poster talked about. I know the Sun is what…a third geneneration star? Is it one of the first formed or close to it third generation stars?
Here’s something else to add to the equation. Maybe our big bang isn’t the first or the last big bang. Multiple Big Bangs : NPR
Unlimited possibilities unfold here.
There’s some debate over this - mostly because there’s some debate over absolutely everything.
It seems like the consensus is on the other side. So many events, over so long a time, with so many chance variation, had to lead up to us that it’s hard to imagine another full set of scenarios that would have the same ending over the same time frame.
Just the fact that a moon of such a large comparative size was formed early in the earth’s history seems to be a wildly unlikely occurrence, and there’s no question that the moon has had a profound influence on life.
Some of the people who are against this seem not to like it because Stephen Jay Gould was its first major proponent. He was wrong about a lot of things - the Burgess Shale, for one - and he made a ton of enemies even when he was right. Other scientists have taken up the thread since his death, though. I haven’t read anything in the opposition that is a convincing argument to me.
If we *are *the first sentient race, then we have an obligation to wander the universe, messing with other species genetic codes and setting up enigmatic monoliths in remote locales, before we elevate ourselves into beings of pure energy and/or madness. Hey, it’s the rules.
There might have been but we killed them and ate them.
I’ve probably posted this before but it is the one image I get whenever someone brings this question up again. What I see is the galaxy spinning before me and within the galaxy there are little lights lighting up and then snuffing out all over it. (Well, mostly in the outer arms) The little lights are like fireflies. One lights briefly in one place and then fades, another lights and fades. There are many fireflies but they don’t stay lit for long and are rarely close to one another. The lights represent civilizations capable of external communications. In terms of the age of the galaxy they are frequent but very short lived, and the galaxy is vast. Why are they so short lived? Some of them are destroyed externally, some destroy themselves. Some simply lose interest. Some evolve past the point where we would recognize each other. In any case, while we are in existence here on Earth there may well be (some arbitrary large number) of other civilizations out there, but not necessarily any that are close enough, AND capable enough, AND interested enough, to communicate with us.
Let’s look at this. We have done some pretty good examination of the Moon, and it seems to be pretty lifeless. We have done a little examination of Mars, without finding any life, yet. We have a glimpse of Venus, nothing yet. We haven’t been able to look at any other body in the universe that might support life, just as we know it, in detail. Maybe that has something to do with not finding extra-terrestrials.