Evolution: the Facts.

[randman]

There is no directionality in evolution

Maybe so but evos assert there was a direction and that was from unicellular life to ever novel forms of life and so greater complexity that we see today. That's their story. To dismiss that by saying, well, evolution has no direction is a little disingenuous.

It certainly had a direction, right? if you believe in common descent.

 

[steenkh]

Maybe so but evos assert there was a direction and that was from unicellular life to ever novel forms of life and so greater complexity that we see today. That's their story. To dismiss that by saying, well, evolution has no direction is a little disingenuous.

It certainly had a direction, right? if you believe in common descent.

Evolution has a single direction: survival. It does not have a direction towards, say, humans. Common descent does not indicate a direction towards any particular target.

 

[randman]

Evolution has a single direction: survival. It does not have a direction towards, say, humans. Common descent does not indicate a direction towards any particular target.

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

 

[steenkh]

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

What apparent direction? Is it a direction that single-celled organisms evolved into all life forms?

By the way, single-celled organisms are still with us, so they have not been lost as we would have expected if evolution had a direction. On the contrary, measured by biomass, single-celled organisms are the most successful on Earth!

 

[Dinwar]

Maybe so but evos assert there was a direction and that was from unicellular life to ever novel forms of life and so greater complexity that we see today.

This is simply not true. EVERY book on evolution I've read stresses that evolution is, at the largest scales, non-directional (many argue that any apparent directionality is a statistical artifact). So you're no longer debating evolution, randman, but some straw man version you've concocted. I suggest reading REAL evolutionary biology books and journal articles, not the fringe lunatics who think mosasaurs evolved into whales.

 

[ehcks]

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

That's not a direction, that's an outcome. Direction implies intent. There was no intent for multi-cellular life, it just happened to be more successful at what it did, and so came out that way.

There was no intent for humanity to exist. We are just very successful at living.

Edit: Let me bold that. Even outside an evolution argument, I think it's important.

 

[GungHo]

Maybe so but evos assert there was a direction and that was from unicellular life to ever novel forms of life and so greater complexity that we see today. That's their story. To dismiss that by saying, well, evolution has no direction is a little disingenuous.

It certainly had a direction, right? if you believe in common descent.

How many ways and from how many people does something be need to be explained to you in order for you to understand the premise, even if you don't agree with it?

 

[jimbob]

Here's a new attempt:

Drunkard's Walk

 

[Craig B]

Drunkard's walk, yes. Organisms develop in all directions. If you end up with less than the minimum necessary complexity you die. We therefore simply don't see the ones that do this, even if they're in the majority. The only ones we see are those that happen to have evolved in the opposite direction.

An intelligent designer: who needs one?

 

[Dinwar]

Drunkard's walk, yes. Organisms develop in all directions. If you end up with less than the minimum necessary complexity you die.

That's the Left-Hand Wall Rule. The Drunkard's Walk is random variation between either two gutters (areas where once you get in, you can't get out; in biology, that usually means death of the organism/species) or a wall and a gutter (one limit you simply can't get past, such as minimum simplicity, and one gutter). The point of the Drunkard's Walk is that the drunkard always ends up in the gutter, eventually--the question is what happens between the bar and the gutter.

Unless I'm mistaken?

 

[Lowpro]

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

You picked humans out of the massive labyrinth of everything ELSE that lives, has EVER lived, and you imply direction?

First off, do not give humans too much credit on evolution, because we suck except at intelligence, and even you are a mighty blow against that grade -.-

 

[Bram Kaandorp]

You picked humans out of the massive labyrinth of everything ELSE that lives, has EVER lived, and you imply direction?

First off, do not give humans too much credit on evolution, because we suck except at intelligence, and even you are a mighty blow against that grade -.-

But humans can think, therefore they are special.

Or was it:

Humans can think and therefore they think they're special.

It would really be a bummer for creationists and IDers when someone finally finds alien life.

I just hope there aren't any fundamental religious leaders at the time, or else we'll probably get a Krikkit event.

 

[Lowpro]

But humans can think, therefore they are special.

Or was it:

Humans can think and therefore they think they're special.

It would really be a bummer for creationists and IDers when someone finally finds alien life.

I just hope there aren't any fundamental religious leaders at the time, or else we'll probably get a Krikkit event.

No, sure as the sun rises they will be Jehova's Witnesses spreadin' the good word!

 

[Bram Kaandorp]

No, sure as the sun rises they will be Jehova's Witnesses spreadin' the good word!

Either that, or someone, somewhere, will think "It'll have to go".

Not that I really think it very likely, but it is possible nonetheless.

 

[pakeha]

Maybe so but evos assert there was a direction and that was from unicellular life to ever novel forms of life and so greater complexity that we see today. That's their story. To dismiss that by saying, well, evolution has no direction is a little disingenuous.

It certainly had a direction, right? if you believe in common descent.

It's interesting to see just how wrong you are, randman.
No one claims there was a 'direction'.
Why persist in attacking this strawman?

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

There is no apparent direction, randman.
There are outcomes.

 

[Prometheus]

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

"Apparent" is the key word here, and that appearance is an illusion of bias. That same single-cell organism which is the common ancestor of all known life also evolved in millions of other 'directions' resulting in the staggering diversity of single-celled life that exists today. Only a vanishingly small fraction of its descendants are multi-cellular.

 

[jimbob]

Maybe so but evos assert there was a direction and that was from unicellular life to ever novel forms of life and so greater complexity that we see today. That's their story. To dismiss that by saying, well, evolution has no direction is a little disingenuous.

It certainly had a direction, right? if you believe in common descent.

It's interesting to see just how wrong you are, randman.
No one claims there was a 'direction'.
Why persist in attacking this strawman?

Ok, but evos say humans and all life forms evolved from a single-cell organism, right?

Why the apparent direction then?

There is no apparent direction, randman.
There are outcomes.

All multicellular organisms had unicellular ancestors, most of life on Earth is still unicelllular and thse also had unicellular ancestors. The apparent dierction is simply because some of the more visible organisms exist. There is a school of thought that viruses originated from living organisms, so that would suggest that there is also a direction towards more simplicity.

The Devil facial tumor certainly evolved from the cells of a tasmanian devil, but has outlived many of its hosts. This is an example of a unicellular form of life evolving from a mammal fairly recently.

 

[Wowbagger]

Why the apparent direction then?

I think the best way to answer this would be to say:

There isn't so much as a direction, but a niche to fill.

If there is an opportunity for cells to work together, as a colony, that niche would be filled. If there is an opportunity for those "colonial" cells to become more specialized over time, those niches would be filled, as well. Etc.

If, in the case of viruses, there is an opportunity to survive and thrive in a more simplified manner, (feeding off the complexity now present in other cells), then that niche will be filled.

Over time, it creates the illusion of direction. But, at its root, it's just life filling any and all available niches they have an opportunity to get into.

Natural Selection provides a mechanism by which these niches could get filled more effectively, over time.

 

[Bram Kaandorp]

All multicellular organisms had unicellular ancestors, most of life on Earth is still unicelllular and thse also had unicellular ancestors. The apparent dierction is simply because some of the more visible organisms exist. There is a school of thought that viruses originated from living organisms, so that would suggest that there is also a direction towards more simplicity.

The Devil facial tumor certainly evolved from the cells of a tasmanian devil, but has outlived many of its hosts. This is an example of a unicellular form of life evolving from a mammal fairly recently.

Another reason for the apparent direction is:

We (humans) are multicellular and think about life.

If we weren't as sentient as we are, we wouldn't be here discussing the apparent direction of evolution. Just look at dogs and bears for an example.

 

[Dinwar]

And if we were unicellular we wouldn't be talking about apparent direction, because it would be trivially obvious that life had remained nearly exclusively unicellular, with only a few weird outliers.