When the sun burns out

[Tibby]

@SentientMeat

Of course, Anne, but in a thousand million years there won’t be anything like “us” about anyway - a billion years is how long multicellular life has existed on Earth. Heck, even the Cambrian explosion was a mere 550 million years ago, before which there were only jellyfish and the like.

We can’t always predict the future based on what has occurred in the past.

I believe that a good argument can be made in favor of the position that humans may have reached a point of biological evolutionary stagnation. Rephrase: we have changed a lot in the past, but we may not change much in the future.

Biological evolution has fueled the engine of change for species since the spark of life arced on earth billions of years ago – human evolution was no exception, our ancestors changed with the best of them. Species will continue to evolve far into the future, as well. But, does this apply to all species? Well, it will certainly apply to all species that must adapt to a changing environment, lest they become extinct. And it will certainly apply to all species whose breeding habits are predictable and tend toward improvement. Does it necessarily apply to humans from this point in time forward? I don’t believe that it does.

Unfortunately, this is a hypothesis that cannot be readily fleshed out by comparison to similar cases, because we are unique. We are unique in that we are at the tip of the spear with regard to sapient biological evolution on earth. I posit that our species crossed a particular threshold at some point over the last few millennia and this threshold is one that leads to evolutionary stagnation.

Actually, I believe that the threshold we crossed was a two-step process:

Step 1) Who or what adapts? We made the switch from a species adaptable to a changing environment to a species that changes it’s environment. Mild to moderate environmental change no longer necessitates physiological adaptation in our species; technological evolution is all that is required. Since environment change is the conditio sine qua non of biological change, negation of environmental stressors must impede the forward thrust of biological evolution.

Step 2) Breeding habits. Ultimately, biological evolution is expressed through the breeding habits of species. If certain qualities are deemed beneficial to the survivability of a species, they must be breed into the species one flagrante delecto at a time, many times, times many. This is how species change over time; this is why species typically improve over time. This system has worked well, historically, for all species that have sex (viruses, bacteria and Michael Jackson have their own way of evolving). This system works particularly well in sexual species whose sex drive is driven instinctually. But what about us tip-of-the-spear, super-sapient humans? I have more faith that my cat will mate with the best that her species has to offer than I will have in my daughters choices (believe me, when they start dating in 15 years, I’m going to screen every shaggy-haired, motorcycle-riding miscreant** they bring home with a fine tooth comb…and a cattle prod).

We no longer rely on instinct to do what is best genetically for the survivability of our species – we rely on our penises. Our penises usually forgo the strongest and brightest for the loosest and largest breasted ( :D…just kidding, a little). At best, I believe that average people with average qualities breed most readily in contemporary humans. This is not a value judgment and I’m not saying that this is necessarily a bad thing (I don’t want to be accused of being a proponent of eugenics). However, breeding average traits genetically leads to biological evolutionary stagnation…IMO.

Bottom line: I don’t believe that we humans, even with mild to moderate environmental changes, will be evolving into silicon-based, muscle-bound brainiacs anytime in the foreseeable future.
On the other hand, 5 billion years is a bit beyond the foreseeable future, and most likely enough time to present our species with severe environmental changes, so some change is, begrudgingly, inevitable.

**I used to be one of them 2 decades ago, so I know what to look for

[bup]

Our oceans won’t boil away - computer models have already been tested that slowly increase the earth’s orbit - all you need to do is set a kilometer-wide asteroid on an orbit just outside earth’s that gives it a little tug every time it goes past.

Also, the old “common wisdom” about the earth being swallowed when the sun goes supernova is wrong - if you take into account that the sun will have a lot less mass when it dies than it does now, the radius of the sun does not reach 93 million miles.

My best guess? Whatever we evolve into will play some astronomical billiards, using gravity to pull a bunch of brown dwarves together - and they’ll build a new sun - say, half a light-year away. Then they’ll set sail - moving the whole planet. It’ll be cold and they’ll live underground for the trip, but then they get about 10 billion more years.

[levdrakon]

Look, I hate to be the one to tell you all this, but someone has to. The sun went red giant a billion years ago. Humans were technologically advanced enough to put us into a digital matrix, and that’s where we’ve been living ever since. We’re never actually going to experience the death of our sun. We just reset the program every 10,000 years or so.

[jawdirk]

@Dr. PoopiePants

And it will certainly apply to all species whose breeding habits are predictable and tend toward improvement… (believe me, when they start dating in 15 years, I’m going to screen every shaggy-haired, motorcycle-riding miscreant** they bring home with a fine tooth comb…and a cattle prod).

Dude, you’re refuting your own argument.

We no longer rely on instinct to do what is best genetically for the survivability of our species – we rely on our penises. Our penises usually forgo the strongest and brightest for the loosest and largest breasted ( :D…just kidding, a little)… Bottom line: I don’t believe that we humans, even with mild to moderate environmental changes, will be evolving into silicon-based, muscle-bound brainiacs anytime in the foreseeable future.

Hey, my girlfriend is as muscle-bound brainiac as they come. You can have your loose largest breasted :D.

But seriously, there are all sorts of genetic trends in humans. They are called classes. And having a lot of kids is only the best long-term strategy if most of them are going to die off before they breed. Otherwise, it just leads to war, and you know which kids are going to die in the next war: the poor ones.

Personally, I think humans are breeding to become underachievers. It’s better to stay under the radar, and use quiet social manipulation to get ahead, than to try to out-think everyone.

[Der_Trihs]

@Dr. PoopiePants

Step 1) Who or what adapts? We made the switch from a species adaptable to a changing environment to a species that changes it’s environment. Mild to moderate environmental change no longer necessitates physiological adaptation in our species; technological evolution is all that is required. Since environment change is the conditio sine qua non of biological change, negation of environmental stressors must impede the forward thrust of biological evolution.

Environmental adaptation is an evolutionary dead end anyway; once the species adapts well to it’s niche, evolution stagnates. Have you ever read The Red Queen’s Race ? It postulates that the driving engine of most evolution is other species and especially your own species, not the environment. We are still evolving due to the ravages of disease, for example.

@Dr. PoopiePants

Step 2) Breeding habits. Ultimately, biological evolution is expressed through the breeding habits of species. If certain qualities are deemed beneficial to the survivability of a species, they must be breed into the species one flagrante delecto at a time, many times, times many. This is how species change over time; this is why species typically improve over time. This system has worked well, historically, for all species that have sex (viruses, bacteria and Michael Jackson have their own way of evolving). This system works particularly well in sexual species whose sex drive is driven instinctually. But what about us tip-of-the-spear, super-sapient humans? I have more faith that my cat will mate with the best that her species has to offer than I will have in my daughters choices (believe me, when they start dating in 15 years, I’m going to screen every shaggy-haired, motorcycle-riding miscreant** they bring home with a fine tooth comb…and a cattle prod).

First, it’s not about being the best, it’s about being well adapted. Species don’t “improve” over time, they just adapt. “Survival of the fittest” is a political phrase coined by the early Social Darwinists; it’s not how evolution actually works.

In this case however, there is an obvious selection for a useful ability : persuasiveness. The guy who can talk a woman into bed is likely to leave more kids than one who can’t.

@Dr. PoopiePants

We no longer rely on instinct to do what is best genetically for the survivability of our species – we rely on our penises.

That’s all we’ve ever done.

In closing, you’re also forgetting genetic engineering, cybernetic enhancement, and so on. Within a few decades at most, I doubt natural genetics will matter much at all for humans, so your argument is moot anyway.

@bup

Also, the old “common wisdom” about the earth being swallowed when the sun goes supernova is wrong - if you take into account that the sun will have a lot less mass when it dies than it does now, the radius of the sun does not reach 93 million miles.

Semi- nitpick : I know what you mean, but our sun won’t ever go supernove; it can’t, it’s much too small. It will expand into a red giant, then throw off lots of hot gas before and as it collapses, but it won’t supernova.

[chappachula]

I don’t think there is anything that can wipe us out now

@Der Trihs

Offhand :
Nearby supernova.
Our galactic core’s black hole(s) eat something big, and produces galaxy-sterilizing radiation.
A near pass by a massive object pulls Earth into an uninhabitable orbit.
Out of control Von Neumann machines ( we can’t build them yet, but eventually . . .)
Massive asteroid strike renders the Earth molten.
Our slightly variable star turns out to be a bit more variable than we thought. < sizzle >
Runaway greenhouse effect; Earth becomes Venus II.

what about GW Bush?
(Sorry, but somebody had to say it…)

mods–yeah, I know this is GD. But I couldn’t resist. Sorry…I won’t do it again, I promise…

[mks57]

According to the professor who taught my astronomy class, we have much less than five billion years. The Sun’s energy output slowly increases as it ages. This will eventually force the Earth into thermal runaway, like Venus, from the greenhouse effect of water vapor. We may only have a billion years before the Earth becomes uninhabitable.

[bup]

@mks57

We may only have a billion years before the Earth becomes uninhabitable.

And I’ll probably spend 999 million years wasting time before I get serious about doing something about it…

[Bryan_Ekers]

@Der Trihs

Semi- nitpick : I know what you mean, but our sun won’t ever go supernove; it can’t, it’s much too small. It will expand into a red giant, then throw off lots of hot gas before and as it collapses, but it won’t supernova.

Well, it won’t go supernova because it’s too small and it’s not part of a close binary star system. It’ll flare up to a red giant for a while and the core will stabilize as a white dwarf for a long long loooooong time.
If the sun was about 44% more massive, it’d pass the Chandrasekhar Limit and go red giant - white dwarf - neutron star. In any case, Earth won’t be the healthiest place to be.