Are we alone.... The answer is ''Yes''

maninasia

I like to call it the 'Perspective Paradox', if we are only one of trillions of planets why do we think we are so unique?

maninasia

Capt'n Midnight wrote: »

what if it's a beserker probe ? :eek:

What if it's an Analleaki Probe?

dyer

the cylons weren't all that bad in the end

Capt'n Midnight

maninasia wrote: »

The Fermi paradox is not a paradox, it's just an observation based on very poor technological capability.

As I stated already, we can't even figure out if Mars has life yet (the latest multi billion probe can only scrape 6cm into the surface of Mars), let alone all the moons and gas giants in our solar system, let alone any other solar system light years away.

If a planet supports life, and it isn't at the very start or very end of life then it will be easily detectable,

simulations like daisyworld show that life can easily enter feedback loops that modify the environment to it's advantage.

If any body in the solar system had enough life to be anything other than on the brink of extinction then it's presence would be detected spectroscopically from the composition of gases in the atmosphere

(some chemical reactions can mimic this and that creates some uncertainty -but we can be certain that mars doesn't have a lot of living organism (unless they are frozen solid)

maninasia

The gold standard would be nucleic acid testing in terms of bacterial life here on Earth, not spectroscopic testing. As you mentioned yourself it is difficult to ferret out the difference between gas produced metabolically by microorganisms or by chemical reactions. There are huge differences between bacteria, methanogenic, aerobic, anaerobic...it's hard to predict which gases would be emitted by microbial action. According to earlier Voyager experiments, life may already have been detected but the results ignored due to perchlorate contamination.

And life is life, and why would it be close to extinction on Mars if it lasted billions of years? What does that mean?

Besides we haven't really done any proper analysis of the moons in our solar system beyond our own moon, they are some great candidates. Here's a nice summary.

http://www.space.com/15716-alien-life-search-solar-system.html

In fact we know very little about our own subsurface biosphere.
http://www.astrobiology.com/news/viewpr.html?pid=38715

Capt'n Midnight

maninasia wrote: »

The gold standard would be nucleic acid testing in terms of bacterial life here on Earth, not spectroscopic testing. As you mentioned yourself it is difficult to ferret out the difference between gas produced metabolically by microorganisms or by chemical reactions.

it's easy

all you do is detect non-equilibrium quantities of substances that react with each other and rule out volcanoes if the concentrations are high enough (it's not quite that simple, but nearly - with mars the concentrations are very low )

maninasia

If it was easy it would have been done already. Gold standard of Earth type life should be direct detection using DNA/RNA/protein analysis, however the Curiosity probe was only designed to detect 'conditions that might support life or show evidence of life in the past', which I find very curious myself! It was obviously designed by geologists and space scientists, not biologists. It also has no drill to get decent samples from the subsurface.
Great probe but missing some tools.

Curly Judge

maninasia wrote: »

If it was easy it would have been done already. Gold standard of Earth type life should be direct detection using DNA/RNA/protein analysis, however the Curiosity probe was only designed to detect 'conditions that might support life or show evidence of life in the past', which I find very curious myself! It was obviously designed by geologists and space scientists, not biologists. It also has no drill to get decent samples from the subsurface.
Great probe but missing some tools.

It's early days yet.
I have great hopes for Curiosity.

flanna01

Curiosity does not have the tools to detect life on Mars....

The ONLY way that Curiosity could discover life, is by taking a picture of it!

Justin1982

maninasia wrote: »

Yes there is excellent evidence, us. If you see a tree do you think it's the only tree? If you see a fish do you think it's the only fish?

Life as we know it appeared very quickly after the crust cooled on Earth, there are trillions of planets out there, it's close to mathematically impossible that Earth is that unique, plus life is simply an extension of evolutionary processes of replication and entropy, the structure that allows the replication and energy storage and transmission could be made of many different chemistries.

It happens that the only one we know of us is based on DNA and proteins, but we are currently technologically blind as to what is going on out there.

I still disagree categorically. Just because we exist and because life began so early on Earth, doesnt mean anything, except that life is a possibility.

Once you know that life is a possibility then you need to calculate the possibility that life will come into being over a given period of time in conditions similar to Earth. We have absolutely no clue what that probablity is. It could be 1 in 10 chance. It could be 1 in 1 million to the power of 1 billion zillion trillion capillion.

Even with evidence that the sub proteins that form DNA are available in abundance on earth and probably throughout the universe on similar planets, we dont know what the likely hood is that the proteins form together in the pattern that makes up DNA and that the same DNA will end up in some sort of cell which forms life.

We just have no idea. Its wishful thinking to suggest anything.

maninasia

Actually I disagree completely with your conclusions.

- The chemiical ingredients for life as we know it is abundant and widespread through this galaxy and universe
- Physical laws are thought to be the same across the universe
- Life has existed on Earth for over 4.5 billion years, very soon after the crust cooled, it has maintained a solid foothold on Earth ever since through massive climatic events and even through complete changes in athmospheric gases. The point here is that over billions of years Earth has changed so much that it could be deemed to be completely different planets at different times in terms of supporting life and yet life just evolved and thrived through it all (and also had a strong hand in that process of change)
- There is nothing to suggest that Earth and our solar system is particularly unique, neither is our sun
- Most stars that we have been able to analyse closely have proven to harbour a solar system
- The solar system moves through the galaxy and is interacting with other solar systems and molecular clouds, comets are also regularly ejected across space which allows intermixing of material

Why should I equate your idea that life is EXTREMELY unique when everything points to us not being particularly unique?

Also unless we are 1 in a trillion unique, then there will be life in the universe.
It just doesn't look like that does it? What are the odds of that from the facts above? Why are we and the Earth 1 in a trillion SPECIAL?

Plus life is simply an extension of evolutionary processes which themselves come out of the fundamental laws , it does not depend on one type of chemistry, rather it is simply a self replicating entity capable of regulating its metabolism and storing and processing energy. The fixation on life as we know it on Earth is very Earthcentric.

Capt'n Midnight

maninasia wrote: »

- Most stars that we have been able to analyse closely have proven to harbour a solar system

Point of Information
http://blogs.voanews.com/science-world/2013/01/09/studies-find-milky-way-contains-billions-of-earth-sized-planets/

One group, led by Francois Fressin of the Harvard-Smithsonian Center for Astrophysics (CfA), said its studies show 50 percent of stars in our galaxy have a planet the size of Earth or larger closely orbiting them.
...
Perhaps one percent of stars have planets the size of Jupiter, while 10 percent have planets the size of Neptune, according to the Berkeley/ Hawaii team.
...
They suggest planets orbiting close to their stars may even be water worlds, with oceans hundreds of kilometers deep, surrounding a rocky core.

To get life you need a planet in the Goldilocks zone
having a magnetic field to keep hydrogen in the atmosphere is probably essential
having a large moon is possibly essential
having asteroids to deliver light elements after the planet cools is probably essential
having a large Jupiter size planet to protect the planet from planet killers later on is also probably essential

having asteroids delivering heavy metals is highly desirable for advanced civilisation

the odds drop rapidly , and as always the question splits into two parts
did life evolve elsewhere in the universe - probably
will it evolve in to a a civilisation that could contact us by now - almost certainly not

Plus life is simply an extension of evolutionary processes which themselves come out of the fundamental laws , it does not depend on one type of chemistry, rather it is simply a self replicating entity capable of regulating its metabolism and storing and processing energy. The fixation on life as we know it on Earth is very Earthcentric.

the Miller experiment and obeservations of interstellar molecules show that some are more common than others , like you said chemistry is the same all over so it's likely that life would be presented with a similar starting mix

Maximus Alexander

maninasia wrote: »

Actually I disagree completely with your conclusions.

The problem is that without any actual data, you're drawing wild conclusions.

You claim that, because there are trillions of planets in the observable universe, if x is the likelihood that any given planet gives rise to intelligent life, and y is the total number of planets, then:

x * y >> 1

But that is not true if x turns out to be 1 * 10 ^ - 40. And you can't claim otherwise based on anything other than blind faith or desire.

Justin1982

maninasia wrote: »

- The chemiical ingredients for life as we know it is abundant and widespread through this galaxy and universe
- Physical laws are thought to be the same across the universe
- Life has existed on Earth for over 4.5 billion years, very soon after the crust cooled, it has maintained a solid foothold on Earth ever since through massive climatic events and even through complete changes in athmospheric gases. The point here is that over billions of years Earth has changed so much that it could be deemed to be completely different planets at different times in terms of supporting life and yet life just evolved and thrived through it all (and also had a strong hand in that process of change)
- There is nothing to suggest that Earth and our solar system is particularly unique, neither is our sun
- Most stars that we have been able to analyse closely have proven to harbour a solar system
- The solar system moves through the galaxy and is interacting with other solar systems and molecular clouds, comets are also regularly ejected across space which allows intermixing of material

I agree completely. The conditions for life are prevalent throughout the universe. There is probably zillions upon dillions of capillions of planets throughout the universe where the conditions are favourable for life to exist.

maninasia wrote: »

What are the odds of that from the facts above?

I agree again. This is the problem. Its a matter of maths and statistics. The universe as we know it is essentially finite in size. Essentially a sphere of radius 14 Billion light years. We will probably be able to calculate to a degree of accuracy how many planets exist in the known universe, take that number as the top range of planets where life can exist in universe. That number is most likely in the range of 1 Billion Billion.
So you then have to calculate the chance that life takes off on average on one of these planets within the 14 billion years of the universe's existence.
Noone knows that number. There is no evidence that the chance is 1 in 10, where life is inevitable, or if the chance is 1 in a billion billion billion, where life would be almost impossible throughout the known universe, or if the chance would be 1 in 1 Billion Billion, in which case planet earth and maybe 2 or 3 other planets in the Universe have life on them.

maninasia wrote: »

The fixation on life as we know it on Earth is very Earthcentric.

Agree again. We see life throughout Earth and think "Yeah if it started here then its defo everywhere else". Its obvious that if life takes off at all then it evolves. But that doesnt mean that life will definitely take off. That first cell is the sticking point. Noone has ever seen a cell come into existence from a bunch of proteins. Until we do and until we study it, we wont know what the chances are of it happening.

Life on Earth could have been an inevitability. Life on Earth could have been a complete fluke. We just dont know.

Life might exist on other planets in our galaxy and be passing from one planet and solar system to the next.

But we have no evidence of this at all yet.

Justin1982

Capt'n Midnight wrote: »

Point of Information
http://blogs.voanews.com/science-world/2013/01/09/studies-find-milky-way-contains-billions-of-earth-sized-planets/To get life you need a planet in the Goldilocks zone
having a magnetic field to keep hydrogen in the atmosphere is probably essential
having a large moon is possibly essential
having asteroids to deliver light elements after the planet cools is probably essential
having a large Jupiter size planet to protect the planet from planet killers later on is also probably essential

having asteroids delivering heavy metals is highly desirable for advanced civilisation

the odds drop rapidly , and as always the question splits into two parts
did life evolve elsewhere in the universe - probably
will it evolve in to a a civilisation that could contact us by now - almost certainly not

the Miller experiment and obeservations of interstellar molecules show that some are more common than others , like you said chemistry is the same all over so it's likely that life would be presented with a similar starting mix

Bang on the money.

Whatever about life taking off on a planet, the chance of intelligent life getting rooted on a planet is almost zero. We have no idea how much of a goldilocks zone we live in or how many variables turned out in our favour to enable humans to evolve.

We are lucky sons of biachs!

flanna01

Guys.. Let's have a look at the facts...

The Planet Earth is around 4.5 billion years old - This is the accepted age among respected scientists... (Not arguing over this point, it there, there about's).

Ok... Since the crust of the Earth cooled down, it has developed plant life, marine life and land life..... ( I think it's safe to say that this statment is undisputed..?)

Yet... In all of the billions, and more recent millions of Earth years, not one alien instrument has been found.. Not one building that could not be explained, not one carving, painting, sculpture.....Nothing!

Going back to my original post... I was not doubting the possibility of the Universe harboring life - I would even say it is a certainty in my opinion..

My statment was... That we have never been visited by an alien race. We will never be visited by an alien race. We will never communicate with another race.

Two clear pointers are: If we were going to be visited by our galactic neighbours - they would have called by before now. Secondly: The distance between us is too far... Much too far.

Capt'n Midnight

Justin1982 wrote: »

We have no idea how much of a goldilocks zone we live in or how many variables turned out in our favour to enable humans to evolve.

We are lucky sons of biachs!

Forgot to mention about size of the planet.

Any smaller and we'd be like Mars and loose a lot of the atmosphere - then again stuff like water bears wouldn't care

Any larger and it would be difficult to leave the planet without using nukes like project Orion. And that would be very difficult if heavy metals weren't delivered by asteroids.
Saturn V could get 1.5% of it's takeoff weight to escape velocity
( The Shuttle's payload was only 1% of takeoff weight )


Very roughly you can use the rocket equation to predict the number of stages needed. On earth we generally use two stages to low orbit and three to get to geosynch orbit or escape velocity. Each stage gives ~ 4km/s delta-V

So let's look at ET visiting a moon of their own planet.

Surface gravity on Neptune is 1.2 times ours. So if we could survive the temperature and pressure we'd just be a bit heavier. But the escape velocity is over twice that of the Earth. So to break free using our technology you'd need a Saturn V weighing 200,000 tonnes.

For Saturn (surface gravity 1.16 times ours) to get to three times the velocity you'd need a 13.3 million tonne rocket

For Jupiter (surface gravity 1.24) it's 5 times the escape velocity so the Saturn V would be 59 billion tonnes - ET won' t need to phone home because they will still be at home.




If we evolved on a water planet then it would be very difficult to smelt metals and other technologies. Though you could use icebergs and shells and gas bags but not easy.

dyer

flanna01 wrote: »

My statment was... That we have never been visited by an alien race. We will never be visited by an alien race. We will never communicate with another race.

I've been fortunate enough to witness ufo's on a handful of occasions which is why i'm fascinated by all of this. One experience in particular stood out from the rest, think something along the lines of a science fiction movie and you wouldn't be far wrong. That begs the question, do they belong to us or not? For all i've read into the subject and from what i've experienced, i don't think that they do. You can take that as you like, i'm not here to force my beliefs on anyone. If it turns out that they are man made objects, some truly amazing technology is being kept hidden from the world.

Gwynston

Some really interesting discussion here everyone! :cool:

Capt'n Midnight wrote: »

To get life you need a planet in the Goldilocks zone
having a magnetic field to keep hydrogen in the atmosphere is probably essential
having a large moon is possibly essential
having asteroids to deliver light elements after the planet cools is probably essential
having a large Jupiter size planet to protect the planet from planet killers later on is also probably essential

having asteroids delivering heavy metals is highly desirable for advanced civilisation

the odds drop rapidly

But that's still working out the odds based on what we observe here on Earth. The list of supposed coincidences that have led to where we are now, are only observable because of where we ended up. A different set of coincidences doesn't make the odds of life hugely more unlikely, just the form of life as we observe it.

Take for example just one of those requirements: Jupiter's role in protecting us from asteroids. Maybe it does (although some people hypothesis it might actually do the opposite), but the fact is asteroid impacts have had a direct influence on how life HAS evolved. We wouldn't be here if the dinosaurs hadn't been wiped out! So asteroid impacts don't preclude the formation of life, even if they might not be great for some forms of life.

One could argue about some of those other prerequisites too. They're just from our point of observation looking back at how WE got here. There are possibly other scenarios and other possible outcomes.

According to David Darling, the Rare Earth hypothesis is neither hypothesis nor prediction, but merely a description of how life arose on Earth. In his view the theory does nothing more than select the factors that best suit the case.

What matters is not whether there's anything unusual about the Earth; there's going to be something idiosyncratic about every planet in space. What matters is whether any of Earth's circumstances are not only unusual but also essential for complex life. So far we've seen nothing to suggest there is. B]Darling, 2001[/B

Capt'n Midnight

Gwynston wrote: »

but the fact is asteroid impacts have had a direct influence on how life HAS evolved. We wouldn't be here if the dinosaurs hadn't been wiped out! So asteroid impacts don't preclude the formation of life, even if they might not be great for some forms of life.

It's reckoned (by who ?) that we got hit many times during the (late?) heavy bombardment by BIG asteroids, as in planet-killers that could boil the seas and effectively sterilize the biosphere

mickey mouse ones like the KT didn't change much. Yes one branch of vertebrates benefited relative to another but that's like comparing a cold to the flu that was the Permian Extinction or even comparing the Permian to what could have happened to Snowball Earth.



What would have happened if Shoemaker Levy 9 had hit earth ?



Jupiter gets hit thousands of times more than we do. Don't know the stats but life here would be very different if we got a KT every 60,000 years and a Permian (not sure if asteroid) every quarter million years.

Gwynston

I knew you'd find fault with my picking apart of Jupiter's role! Touché!

I don't have the expertise to do it properly, but my point is that we've got where we are via the history we've unraveled. All we can do is play Sherlock Holmes and deduce all that's occurred based on observation and where we've ended up. We don't know much about the possibilities of what else might have occurred to life given a different set of occurrences that are equally as unlikely as what did happen.

"Intelligent" life has only evolved in the past few million years. Without the KT event, it might have happened earlier on a different branch. Or if we end up not doing so well, it might yet happen again in a few million years, Planet Of The Apes-style (feel free to replace "Apes" with your own likely candidate).

While it seems unlikely how we've got to where we are, maybe it's just those sort of wild variables that inevitably lead to life? Entropy makes things happen and perhaps life is one of the inevitable outcomes?

So it's not so easy to dismiss life elsewhere based on the Rare Earth idea because there may be a lot of other "Rare Planet X" scenarios elsewhere that have also led to life via a different set of coincidences....

maninasia

Gwynston wrote: »

I knew you'd find fault with my picking apart of Jupiter's role! Touché!

I don't have the expertise to do it properly, but my point is that we've got where we are via the history we've unraveled. All we can do is play Sherlock Holmes and deduce all that's occurred based on observation and where we've ended up. We don't know much about the possibilities of what else might have occurred to life given a different set of occurrences that are equally as unlikely as what did happen.

"Intelligent" life has only evolved in the past few million years. Without the KT event, it might have happened earlier on a different branch. Or if we end up not doing so well, it might yet happen again in a few million years, Planet Of The Apes-style (feel free to replace "Apes" with your own likely candidate).

While it seems unlikely how we've got to where we are, maybe it's just those sort of wild variables that inevitably lead to life? Entropy makes things happen and perhaps life is one of the inevitable outcomes?

So it's not so easy to dismiss life elsewhere based on the Rare Earth idea because there may be a lot of other "Rare Planet X" scenarios elsewhere that have also led to life via a different set of coincidences....

It's simple, WE are alive to reason because all our ancestors lived before us. If something different happened THEY would be alive to reason because all their ancestors lived before them. I think some posters have fallen badly for the 'just so' logical fallacy.

The earth is not just rare, it IS unique. I am unique, you are unique, big frigging deal! However if a given alien was asked to point out the difference between me and Mr Chen in Beijing , China they would have a bloody hard time doing it ERGO I am not as unique as I may have thought I was nor is it very important in the bigger scheme of things. In the same vein there is no exact clone of Earth but there are probably lots of similar type watery planets and moons for Earth like life to evolve on.

Plus as I have stated Earth is not a static planet, it has changed massively through billions of years, so which Earth should we be looking for?

The Goldilocks zone is pretty meaningless, it changes according to the wind, and ignores the excellent potential of life bearing moons (there are 20x moons to planets in our own solar system) for earth type life far outside its typical defined limitations. Again what geological era, atmospheric conditions, plate tectonic requirents, species type and abundance, first common ancestor etc. are we talking about when we say Goldilocks zone? Too many variables to be of much use. In our own solar system some of the best current candidates for Earth type life are currently OUTSIDE the Goldilocks zone, namely Europe and Encepheldus.

As for intelligent life, that has existed for hundred of millions of years on earth, not just when apes evolved. The dinosaurs were intelligent, the reptiles were intelligent, the birds are intelligent, the fish are intelligent and even squid and octopi ARE intelligent!

maninasia

Capt'n Midnight wrote: »

It's reckoned (by who ?) that we got hit many times during the (late?) heavy bombardment by BIG asteroids, as in planet-killers that could boil the seas and effectively sterilize the biosphere

mickey mouse ones like the KT didn't change much. Yes one branch of vertebrates benefited relative to another but that's like comparing a cold to the flu that was the Permian Extinction or even comparing the Permian to what could have happened to Snowball Earth.



What would have happened if Shoemaker Levy 9 had hit earth ?



Jupiter gets hit thousands of times more than we do. Don't know the stats but life here would be very different if we got a KT every 60,000 years and a Permian (not sure if asteroid) every quarter million years.

Well yes it would be different but we just don't know what would have happened. A species may have evolved that reached our technological heights faster due to some selective pressures? Life may have spread to other planets or moons easier as vast quantities of material were ejected into the solar system? We don't know because we are arguing from our perspective more than anything.

Capt'n Midnight

maninasia wrote: »

Well yes it would be different but we just don't know what would have happened. A species may have evolved that reached our technological heights faster due to some selective pressures? Life may have spread to other planets or moons easier as vast quantities of material were ejected into the solar system? We don't know because we are arguing from our perspective more than anything.

I'm not sure another species would have evolved earlier.

Don't forget that it's still an arms race out there.

Yes dinosaurs had big brains compared to the competition but by todays standards even the brightest would be like dumb birds. Evolution doesn't regress, useful adaptions are kept.



Anyway even if all the vertebrates had been wiped out we'd still have a contender in the Octopus. Considering how different stuff like parrots and dolphins are to us the world view of an octopus would be interesting.

ps200306

Capt'n Midnight wrote: »

Evolution doesn't regress, useful adaptions are kept.

I'm not sure that's a correct way of looking at it. Regression implies "disimprovement". Evolution is not about improvement or disimprovement, it is about fitness. And fitness is about reproductive success. Is a peackock's tail an improvement? Yes, in the sense that it attracts the ladies. Apart from that it seems a hell of an impediment that any sensible organism would ditch. On the other hand -- much more seemingly useful things have been ditched ... even vision, in the case of blind mole rats.

Much is made of "intelligence" in other mammals and invertebrates like octopi, and it seems like intelligence is certainly a continuum, but humans are so different from any other life on earth in terms of their ability to manipulate the environment that I think it is facile to talk about the inevitability of intelligence arising. If we're going to include dinosaurs and dolphins as "intelligent", then it's not the sort of intelligence that is going to seek out life on other planets. We are completely unique on our planet in that respect ... and we have no idea if the selection pressures that drove us to become such generalists are common elsewhere in the universe. Among the millions of species on planet earth, we are the only ones who behave as we do.

Capt'n Midnight

ps200306 wrote: »

Is a peackock's tail an improvement?

a peacock can't revert back to fins and gills, but it's descendants will have lots of other useful genes tucked away for the future. In a predator prey relationship if intelligence is useful then it will be selected for. And since there are many species of both it's a rising tide.

Suppose 300 million years ago a large brain, warm blood, and upright stance would have been over kill and well past the point of diminishing returns for the organism to support. Today on the Savannah they'd be kinda handy. (but not so handy in other places)

It's like today a local manufacturer can't churn out shoddy goods because the competition from China is much tougher than it was in the past, and because of that everyone else has had to up their game so even if China disappeared tomorrow you still can't churn out crap because those who have competed with the Chinese would completely wipe you out.

but humans are so different from any other life on earth in terms of their ability to manipulate the environment that I think it is facile to talk about the inevitability of intelligence arising

Beavers also manipulate the environment

Look up the Gaia hypothesis single celled organisms drive clouds , and hence rainfall and water on land and levels of solar radiation. They also drive plate tectonics.


It could be that we've had more competition and that our moon has caused more interesting enviroments down here. Maybe we are the first ?

It took billions of years to get from the first life to pond scum (green algae) and half a billion to get from the first flat multi cellular organisms to proper animals ("that thing looks weird") and it's been accelerating ever since

ps200306

Some good points there. On the other hand, the extinction rate for species has continued unabated since diversification began. Six million years seems to be the average species lifetime. (That stat may be out of date -- I read it many years ago). Will we be the species that beats the odds? Maybe, maybe not. We don't really have much to go on.

Gwynston

ps200306 wrote: »

Some good points there. On the other hand, the extinction rate for species has continued unabated since diversification began. Six million years seems to be the average species lifetime. (That stat may be out of date -- I read it many years ago). Will we be the species that beats the odds? Maybe, maybe not. We don't really have much to go on.

That stat is almost certainly out of date as we've surely accelerated many species' extinction rate just in the past few thousand years, and especially in the past couple of hundred!

Capt'n Midnight

ps200306 wrote: »

Some good points there. On the other hand, the extinction rate for species has continued unabated since diversification began. Six million years seems to be the average species lifetime. (That stat may be out of date -- I read it many years ago). Will we be the species that beats the odds? Maybe, maybe not. We don't really have much to go on.

Tell that to the tuatara or horse shoe crab or the bacteria in the stromatolites in Shark bay

Species can evolve very quickly - look at the fish in African lakes



Our species will change. Even if there is no selective pressure there will still be genes that go extinct and mutations will happen.

BUT we share genes so it's very unlikely that the species will split, yes our ancestors will be different, but with natural selective pressures reduced it's unlikely we will go the way of the elephant - in the last three generations the % with tusks has fallen drastically - perhaps this is why Indian elephants don't have tusks ?

maninasia

Capt'n Midnight wrote: »

Tell that to the tuatara or horse shoe crab or the bacteria in the stromatolites in Shark bay

Species can evolve very quickly - look at the fish in African lakes



Our species will change. Even if there is no selective pressure there will still be genes that go extinct and mutations will happen.

BUT we share genes so it's very unlikely that the species will split, yes our ancestors will be different, but with natural selective pressures reduced it's unlikely we will go the way of the elephant - in the last three generations the % with tusks has fallen drastically - perhaps this is why Indian elephants don't have tusks ?

Natural selection has already been replaced by artificial selection for humans. The future is a whole new ball game for us.

Another common misconception that has come up is the idea that evolution has a direction, that it is the destiny of the next evolved species to 'improve' on the first. That's not how it works, it's simply fitness for the time and environment that the individual and species exist in. As a simple example it's not use to evolve better eyes if the world is now dark or a bigger brain if the key to survival is energy expenditure.

I believe it's also possibly for multicellular animals to have descendants that are single celled, although I haven't checked to see if any have been discovered.

Many have the mistaken belief that we are more evolved than bacteria or plants but that is just not true because it depends on what definition you have.. For examples many plants have multiple more genes than we do and have lasted much longer that we have on the planet and have also had a greater impact than we have had, so how are we considered more evolved? The question doesn't make any sense of itself.