Life on earth appeared more or less as soon as conditions were suitable. But it percolated along as prokaryotic cells for 2 billion years. Then somehow one cell swallowed another and instead of digesting it, allowed to take up residence and become, say, a mitochondrian and evolution turned the mitochondria into energy generating machines. Another such became a chloroplast and started generating oxygen in the atmosphere (which was poisonous to most life at the time). Eventually, after another billion and a half years, multi-cellular life evolved. And then dinosaurs who lived for something like 165 million years without developing intelligence (or at least technology). Then a large meteor struck the earth and led to the demise of the dinos and the radiation of the heretofore minor group of mammals. One primitive class of these mammals didn’t develop any particular specialization (unless you count tree-living as a specialization). One genus of these primates developed the ability to raise its forelimbs about its head and swing from trees. A few species of this genus came down out of the trees. Its hands and arms allowed to start developing stone tools. And, for some mysterious reason, develop language and so on.
Everyone of these steps was crucial to lead to us. I don’t deny that there are probably many paths, but this was ours. And we have no idea how difficult any of them were. Perhaps, on average it takes longer than the life of a star to produce eukaryotic cells. We don’t know and have no way of estimating.
One thing I recently read pointed out that even though stars smaller and cooler than our sun might have an estimated life of, say, 100 billion years before they turn into red giants, the lower redder radiation will give less free energy making the development of life harder.
Even if whales and dolphins are as intelligent as humans and even if they have language, they have no physical capacity for technology. It is entirely possible that life is common but technology exceedingly rare.
What you keep describing as static environments are incredibly unstable arrangements. Let’s say we’re all happily homeostasising, but I have 2.1 children per generation and you only have 2.0 children. It won’t take all that long (on geologic timescales) before the entire population carries my genes. And if there is a third guy who is having 2.2 children, he’ll out-breed all of us.
As you say, even plants compete for light. There is no limiting resource, not even an inorganic resource like sunlight, that life isn’t in competition for. The plant that grows tallest, fastest, adapts to lower light, climbs on other plants… these will be selected for. The plant that says “Why can’t we all just get along?” is dead.
I’m still unclear why a pronouncement by a physicist, who should have everything about the speed of light, the mechanics of space travel, the passage of time, and the bleeping Inverse Square Law as part of his second nature, would say anything that stupid. First, he didn’t ignite the Earth’s atmosphere, as promised. And then this?
I don’t think Fermi is the kind of person who would have just forgotten about the inverse square law, if it was relevant.
And consider that humans have discovered exoplanets up to 13,000 light-years distant without benefit of FM broadcasts.
And consider that the era of human human science is only 500 years old; The ETIs Fermi was thinking of would have passed our present state of development millions of years ago.
It is tatally relevant. There is no point in sending a shoutout if no one will hear it. The inverse square law is immutable as our technology stands. We are not broadcasting at extra-light frequencies, so unless you have equipment capable of discerning unimaginably small differences it makes no sense to listen for them. If you find one, you island hop to real prospects, settle/incorporate them, and listen for who is less dim. That takes a long time.
I was not hired at Fermilab, so I’m comfortable calling him an idiot.
Well I guess the same is technically true at an interstellar scale, but I think the following caveats make it moot:
There is no plausible scenario at this time for a species to evolve to travel interstellar distances; we’re assuming interstellar species will travel such distances with (hyper-advanced) technology.
The fact that they have achieved this level of technology already implies a lot about such species.
Space is mostly (unimaginably vast) empty space. Species would not be tripping over each other the way that plants on a landmass (figuratively) are.
Or, if we’re imagining a race to particular resources, and we’re speculating that species may compete to make dyson spheres…we’d see evidence of that. And last year when the 100,000 closest galaxies were surveyed for such features, we found nothing.
If Dyson spheres exist, there are no galaxies saturated with them. This kind of competition is objectively not happening over the vast range we’ve looked so far.
Interesting. I clicked the links, clicked again to Dosage_compensation, and now have a question.
If female humans “silence the transcription of one X chromosome of each pair” then why don’t carriers of hemophilia have a 50% of having the disease? (Or is the silencing done cell-by-cell, and 50% “good” cells is enough not to suffer symptoms?)
X-inactivation happens on a cell-by-cell basis when the developing embryo is at the stage of still being made up of a few hundred or so cells, so the adult woman will end up as a mosaic of cells with one or the other X chromosome deactivated. For hemophilia, having some cells without the defective gene is enough, they don’t all have to be good.
I think Dyson spheres are silly. Hey, we can build solar panels, someday we’ll put solar panels around the whole sun! That’s like ancient Egyptians saying, hey, we can build pyramids, someday we’ll build pyramids that reach to the stars!
Um, no. What we eventually build probably won’t be anything we’re imagining now.
Agreed. For one thing, species with hyper-technology can choose their future bodily modifications by gene-scripting. They would have left behind the ordinary non-volitional path of evolution. (Humanity is coming VERY close to this point, if it has not already.)
Also, technology proceeds vastly faster than biological evolution. It takes species millions of years to evolve wings…but we went from the Wright Brothers to the Moon in under 100 years. So if Interstellar travel is possible at all, it would take place in a cosmic eye-blink.
(And that leads to the scary question: how long do hyper-technological civilizations last?)
