Evolution - clarifications

[uwbrother]

Hi,
It's not a question. There are a few misconceptions around the concept of natural selection that has always bothered me. I'd like to clarify them :-

• There is no "end goal"."Evolution" is a horribly confusing term. It does not imply a march towards a "goal". It does not need "time" to reach a goal. At any given time for any given environment you'll find species adapted, or evolved, for that environment. As environments change, some mutations will die out while others will survive. That's it.
  (Even then, organisms are not necessarily "perfectly adapted". You just have to be better adapted than the one you are competing with)
• You do not 'un-evolve'. There is no such thing as "unevolving". A species can only change to adapt to its current environment. There are places on Earth where due to darkness or muddiness, fish no longer need eyes and they actually lost their eyes. They did not "unevolve". They merely adapted to their environment. They cannot survive in ours and we cannot in theirs. Environments do change and render old adaptations useless or sometimes harmful, but that's not "unevolving".
• "Most evolved" or "highly evolved" does not mean "complex". A hoof (horse's foot) is perfectly evolved for the task it has to perform, even though it's much simpler than feet of many other animals (which are evolved for the task they performed).
• Organisms do not always improveEvolution does not imply that the current state is the best design. Sometimes a less-than-ideal mutation accompanies another mutation that allows you to pass your DNA more successfully. Sometimes environments change. Sometimes you get by with a less than ideal mutation because there wasn't a better one to compete with.
• Better mutations do not always survive. Many species have gone tens of millions of years with relative little change. It's not that they did not have mutations that were better. But current design is probably adapted enough that new mutation did not get a chance to noticeably change the gene pool. Just because an individual has a better mutation it does not necessarily follow that the mutation will change the gene pool.
• Mutations are random. You get a random mutation that may allow you to be more successful in passing your genes. Weather patterns and other changes are also random that disrupt normal eco systems and make new selections and new winners / losers. If you go back 500 million years then we'd have totally different animals.
  (I should clarify, that convergence will still happen. There will still be sea creatures that are agile swimmers. Their bodies will be similar to shark's. They may have different type of eyes or different senses altogether or different locations but ultimately, there are only that many ways of being agile swimmers)
• Natural selection is not random. I know I just said mutations are random, but what survives and what doesn't is anything but random.
• However, everything is not due to natural selection - Some changes happen simply due to genetic drift that over time, change species without any "natural selection".
• Evolution is anything but efficient - Male nipples, enough said.
• It's too early to know whether intelligence and body design that leads to technological advancement is a successful adaptation. Humans may well not only go extinct themselves, but cause a massive extinction due to their actions. If so, then at least on our planet this level of intelligence would turn out to be a poor adaptation that got wiped out by natural selection.
• Evolution does not give you what you need. Sometimes well meaning individuals imply that natural selection will give an organism what it "needs". Evolution isn't smart. If a population has a genetic variant that is more successful in reproducing then that variance increases with each generation and changes the gene pool. But that adaptation may never come. It may happen but not survive long enough to change the gene pool. It may be accompanied by another mutation that makes the individual less competitive. And a whole lot of other reasons why organisms may not adapt. If they always did then there wouldn't be natural extinctions.

I hope it clarifies a few things. Some other concrete examples that demonstrate some of my points above: male nipples

[Gillianren]

Yes, we know. Is there a reason you're telling us this?

[Moose]

Moved to S&T.

[uwbrother]

Ya, cuz lately this has come up in a lot of threads.

[Jens]

It's a bit confusing: it seems like these are problems you have with how other people think of natural selection, or how it's described, rather than with the process itself. Right?

[mugaliens]

Oh, gosh, I love this...

Hi,
It's not a question. There are a few misconceptions around the concept of natural selection that has always bothered me. I'd like to clarify them :-

[LIST][*]There is no "end goal"."Evolution" is a horribly confusing term. It does not imply a march towards a "goal". It does not need "time" to reach a goal. At any given time for any given environment you'll find species adapted, or evolved, for that environment. As environments change, some mutations will die out while others will survive. That's it.
(Even then, organisms are not necessarily "perfectly adapted". You just have to be better adapted than the one you are competing with)

Ka-Pow! You nailed it. "Survival of the fittest" is very appropriate, but this term fails to hint at genetic variation, which is the other side of the coin. For highly variated species, change is relatively normal, but for species which hardly variates at all, they're considered genetically "fragile."

[*]You do not 'un-evolve'. There is no such thing as "unevolving". A species can only change to adapt to its current environment. There are places on Earth where due to darkness or muddiness, fish no longer need eyes and they actually lost their eyes. They did not "unevolve". They merely adapted to their environment. They cannot survive in ours and we cannot in theirs. Environments do change and render old adaptations useless or sometimes harmful, but that's not "unevolving".

Agreed. Growing and maintaining eyes requires energy, and in the absence of requiring such a gift, the eye-less stand a better chance of surviving, as they require less energy than do the eye'd.

[*]"Most evolved" or "highly evolved" does not mean "complex". A hoof (horse's foot) is perfectly evolved for the task it has to perform, even though it's much simpler than feet of many other animals (which are evolved for the task they performed). [*]Organisms do not always improve

I would argue they always improve to fill their ecological niche, but only to the extent the fires of evolution allow them to. If variation is the norm (and I believe it is), then you'll always find that variations will populate the environment.

Evolution does not imply that the current state is the best design. Sometimes a less-than-ideal mutation accompanies another mutation that allows you to pass your DNA more successfully. Sometimes environments change. Sometimes you get by with a less than ideal mutation because there wasn't a better one to compete with.

Permissive environments allow for genetic expression.

[*]Better mutations do not always survive.

"Better" by who's standards? Nature holds no grudge! It's just life.

Many species have gone tens of millions of years with relative little change.

Lacking changes in environmental pressures, random change only serves to produce offspring which are less suited to the environment than one's parents.

It's not that they did not have mutations that were better. But current design is probably adapted enough that new mutation did not get a chance to noticeably change the gene pool. Just because an individual has a better mutation it does not necessarily follow that the mutation will change the gene pool.

Bingo!

[*]Mutations are random. You get a random mutation that may allow you to be more successful in passing your genes. Weather patterns and other changes are also random that disrupt normal eco systems and make new selections and new winners / losers. If you go back 500 million years then we'd have totally different animals.

Agreed. I think we'd have a difficult time existing 500 my ago.

(I should clarify, that convergence will still happen. There will still be sea creatures that are agile swimmers. Their bodies will be similar to shark's. They may have different type of eyes or different senses altogether or different locations but ultimately, there are only that many ways of being agile swimmers)[*]Natural selection is not random. I know I just said mutations are random, but what survives and what doesn't is anything but random. [*]However, everything is not due to natural selection - Some changes happen simply due to genetic drift...

...or natural variation, which has itself resulted in a more advantageous genetic result over time to that over time...

[*]Evolution is anything but efficient - Male nipples, enough said.

Hardly! My goodness, one might as well say because females have hair that hair is a genetically female trait.

Hair is efficient. So are the various female triats, the vast majority of which are mirrored in males to either more or lessor extent, and vice versa. Just a few hormones at key points in the development cycle.

I hope it clarifies a few things. Some other concrete examples that demonstrate some of my points above: male nipples

Yeah, well, we've discussed that issue... I the meantime, I hope we've also addressed the issue of how evolution manifests itself.

[Strange]

Nice summary. (Although I am worried about your obsession with male nipples.)

Ka-Pow! You nailed it. "Survival of the fittest" is very appropriate, but this term fails to hint at genetic variation, which is the other side of the coin.

I think "survival of the fittest" is very misleading. It has too often been interpreted as "survival of the healthiest/strongest" (this has been abused in some management circles, for example).

Yes, we know. Is there a reason you're telling us this?

It may have been a recent post about modern society allowing people who are not "fit" to reproduce....

(And not everyone knows this; it is useful to have it clearly restated occasionally)

[uwbrother]

I've often tried to come up with a better term and my favourite is "natural selection". "Survival of the fittest" is open to abuse, and anyway there is some randomness that causes "fit" to not necessarily survive. "Evolution" hints towards "progress" or for some people, a march towards "complexity". Natural selection doesn't seem to have other conotations.

[Gillianren]

(And not everyone knows this; it is useful to have it clearly restated occasionally)

That's as may be; this really isn't the place for just giving lessons. They're generally to be an answer to things.

I've often tried to come up with a better term and my favourite is "natural selection". "Survival of the fittest" is open to abuse, and anyway there is some randomness that causes "fit" to not necessarily survive. "Evolution" hints towards "progress" or for some people, a march towards "complexity". Natural selection doesn't seem to have other conotations.

"Natural selection"? You mean the term Darwin himself used instead of the corrupted "survival of the fittest"? Really, the most confusing language about evolution, including that word, is that which was imposed on Darwin's work after he'd written it.

[forrest noble]

uwbrother,

Evolution - clarifications

I really don't know what clarification you have accomplished. Many people here on BAUT are highly educated and already know much of this material. It appears that your point is that of education, which is a good thing. But to just discuss well-known knowledge is not that interesting to most readers since they could just read it on the net if they are interested.

It's not a question. There are a few misconceptions around the concept of natural selection that has always bothered me. I'd like to clarify them :-

OK

* There is no "end goal"."Evolution" is a horribly confusing term. It does not imply a march towards a "goal". It does not need "time" to reach a goal. At any given time for any given environment you'll find species adapted, or evolved, for that environment. As environments change, some mutations will die out while others will survive. That's it. (Even then, organisms are not necessarily "perfectly adapted". You just have to be better adapted than the one you are competing with)

Hence, natural selection. My goal here will be to make some comments to you, that's about it.

As far as end goals, of course not, its natural selection. Nature selects the fittest for the present environment by allowing them to survive and procreate more often than those that are less fit or able to adapt to a changing environment. Your explanation is good.

* You do not 'un-evolve'. There is no such thing as "unevolving". A species can only change to adapt to its current environment. There are places on Earth where due to darkness or muddiness, fish no longer need eyes and they actually lost their eyes. They did not "unevolve". They merely adapted to their environment. They cannot survive in ours and we cannot in theirs. Environments do change and render old adaptations useless or sometimes harmful, but that's not "unevolving".

Again evolution does not have a "forward" direction to it but some species could be called "unevolving." A particular favorable trait in a species might evolve such as sight, but be discontinued in a cave-like environment (as you suggest) because eyes could convey false images in the dark to the brain and those individuals with other senses more acute with little or no eye sight would have a better chance of survival in this environment. It's just a question of how you choose to define the word unevolve.

Evolution is just a term. It implies moving forward as an improved model but the only "improvement" that natural selection considers are the ones that allow better survival and/ or more procreation, this sometimes may mean a simpler creature with less wits but more pro-creation talents. Many members of our species are working on this one as individuals.

* "Most evolved" or "highly evolved" does not mean "complex". A hoof (horse's foot) is perfectly evolved for the task it has to perform, even though it's much simpler than feet of many other animals (which are evolved for the task they performed).

OK

* Organisms do not always improve Evolution does not imply that the current state is the best design. Sometimes a less-than-ideal mutation accompanies another mutation that allows you to pass your DNA more successfully. Sometimes environments change. Sometimes you get by with a less than ideal mutation because there wasn't a better one to compete with.

This sounds right.

* Better mutations do not always survive. Many species have gone tens of millions of years with relative little change. It's not that they did not have mutations that were better. But current design is probably adapted enough that new mutation did not get a chance to noticeably change the gene pool. Just because an individual has a better mutation it does not necessarily follow that the mutation will change the gene pool.

There is no such thing as a better mutation, there are only those which allow better survival and/ or more prolific procreation. It's probably just your choice of words.

* Mutations are random. You get a random mutation that may allow you to be more successful in passing your genes. Weather patterns and other changes are also random that disrupt normal eco systems and make new selections and new winners / losers. If you go back 500 million years then we'd have totally different animals.

OK

(I should clarify, that convergence will still happen. There will still be sea creatures that are agile swimmers. Their bodies will be similar to shark's. They may have different type of eyes or different senses altogether or different locations but ultimately, there are only that many ways of being agile swimmers)

no problem here.

* Natural selection is not random. I know I just said mutations are random, but what survives and what doesn't is anything but random.

Here it might be your choice of words, but Natural selection in the short run may be random concerning small populations and their survival. In the long run it is simply the survival of the fittest as you suggest.

* However, everything is not due to natural selection - Some changes happen simply due to genetic drift that over time, change species without any "natural selection".

The new field of epi-genetics also will come to play here where the environment could change the genetic expression in a living species/ individual discarding death , or procreation as the median. This epigenitic change may be further passed on by genetics. This is still theoretical.

* Evolution is anything but efficient - Male nipples, enough said.

Your example is just a value judgment on your part. What would be the genetic advantage to mammals if the males lost their nipples.There is a type of efficiency here. Don't change what isn't broken.

* It's too early to know whether intelligence and body design that leads to technological advancement is a successful adaptation. Humans may well not only go extinct themselves, but cause a massive extinction due to their actions. If so, then at least on our planet this level of intelligence would turn out to be a poor adaptation that got wiped out by natural selection.

I think we can successfully say that human intelligence and their body design has been a boon to our survival and proliferation as a species. Great adaptations and evolution don't last forever for any species. There are only a few examples of relatively unchanged species over the hundreds of millions of years; that doesn't mean that some dinosaurs that didn't make the cut after 10 million years weren't well adapted, it just means that conditions changed and they were gobbled up or something. Often a species has changed their own environment by their numbers causing their numbers to diminish greatly. Humans may nuke themselves or pollute themselves but I see no ending to them as a species in the foreseeable future.

* Evolution does not give you what you need. Sometimes well meaning individuals imply that natural selection will give an organism what it "needs". Evolution isn't smart. If a population has a genetic variant that is more successful in reproducing then that variance increases with each generation and changes the gene pool. But that adaptation may never come. It may happen but not survive long enough to change the gene pool. It may be accompanied by another mutation that makes the individual less competitive. And a whole lot of other reasons why organisms may not adapt. If they always did then there wouldn't be natural extinctions.

sounds right.

[uwbrother]

I am a junior member and haven't been here for too long. Yet pretty much every day I read posts (sometimes from old-timers) that use one of the misconceptions.

[Gillianren]

I would suggest the place to point them out would be in the thread where the misunderstanding occurs.

[slang]

I am a junior member and haven't been here for too long. Young pretty much every day I read posts (sometimes but old-timers) that use one of the misconceptions.

Junior, Order Of Kilopi, it means nothing here. The only thing you can take away from a high status group is that the poster in question has managed to stay unbanned for a big number of posts. It doesn't necessarily mean (s)he's more right or more wrong than any other poster. The other day I noticed a poster who has been here for eight years, and is still considered a "newbie" by the system, just because he reads more than he posts. *shrug*

I liked your post. It's probably old news for most people here, but you never know who might benefit from it. Who knows, maybe one or two people just causally visiting here may have long lingering questions or doubts answered by your post, and who knows how they might benefit from it in life.

[Canis Lupus]

Hi,
It's not a question. There are a few misconceptions around the concept of natural selection that has always bothered me. I'd like to clarify them :-

[LIST][*]There is no "end goal". ...

I hope it clarifies a few things...

I enjoyed reading your OP, uwbrother, even if I disagree with some of its content. My apologies for the large snip in the quote I have used, but I thought I would concentrate on one point for the time being.

You state "there is no end goal to evolution". At best, one can only say that as opinion, speculation or theory, which may be right or wrong. I have no problem with a "theory of evolution", provided the idea of theory is not lost sight of. To many it is a complete answer, as presently put forward. To others, such as myself, while being impressed with how far the theory explains the mechanics of some of what is occurring in nature, it still leaves open many questions and implications.

An end goal may be difficult to discern, particularly from an individual's point view, but that does not mean one does not exist. The implications of an end goal, however, carry with it baggage which the scientific community, generally speaking, probably finds challenging. I'd hasten to add, I have no grasp of this end goal, however, in observing "nature" and its many wonders, I have been impressed enough to conclude that the way it works dwarfs Man's intelligence, even on a collective scale.

Given my own inferiority in understanding its complexities, one which is shared by all others to some degree (the differences being quite minor between us all when compared to the totality of Nature's intelligence) I'm in no rush to conclude there is no aim to it all. My mind is well and truly open on that point. On the balance of probabilities, I'd go further purely on the basis that something demonstrating intelligence inevitably does so for a reason, even though I may not understand that reason.

On the other hand, if I was an individual who saw no real purpose to my own life and other people's, then I would have to conclude that all those facts, circumstances and occurrences behind my existence, and theirs, had no aim also. When I read the idea that evolution has no aim, I see it more as a subjective viewpoint or comment revealing one's own lack of aims and purposes in life, which suggests upon analyses, very little or no purpose or at least one which fails to satisfy oneself as meaningful. The fact that an idea may generally be held by many, does not change its nature, but rather just creates more pressure for people to think it believable.

If it is really part of the theory of evolution that evolution has no aim, then it is indeed a very proscriptive theory which might explain why some folk reject it vehemently as contradicting too much which they intuitively feel to be otherwise. It seems an unnecessary addition to a good theory, which when kept simple, acknowledging its own limitations, is hard to dismiss, and one when argued from a more limited perspective provides a solid foundation to refute those with contrary ideas.

As far as end goals, of course not, its natural selection. Nature selects the fittest for the present environment by allowing them to survive and procreate more often than those that are less fit or able to adapt to a changing environment. Your explanation is good.

It is interesting reading your response, forest noble, in the way you express yourself. We do inevitably think about "Nature" as an identity, somewhat like ourselves, doing something. It seems unavoidable. Conceptually with us, it is a thing, and this thing appears to possess intelligence and a will, doesn't it?

[uwbrother]

You state "there is no end goal to evolution".
....
If it is really part of the theory of evolution that evolution has no aim, then it is indeed a very proscriptive theory....

Nice post. Except I think you misunderstood a point. I did not say evolution had no "aim". I said it had no "end-goal". There is no body design evolution is trying to achieve. There is no eventual goal evolution is taking species towards.

That's not to say there is no "aim". The aim is to optimize the genetic makeup for a given environment.

[uwbrother]

I am a junior member and haven't been here for too long. Young pretty much every day I read posts (sometimes but old-timers) that use one of the misconceptions.

Did I really type that? Kudos to you readers for actually understanding what I was trying to say. I am ashamed .

I would suggest the place to point them out would be in the thread where the misunderstanding occurs.

But is there a reason why we can't discuss evolution? A lot of topics posted here are old news to a lot of people.

[Canis Lupus]

But is there a reason why we can't discuss evolution? A lot of topics posted here are old new to a lot of people.

That's an interesting question to pose, although in the "Life In Space" sub-forum, the theory is discussed, but in a different manner. There appears to be a lack of general discussion within the scientific community about aspects of the theory of evolution, which is preventing its refinement - its own evolution. To some extent, I have concluded this is because of a type of political dynamic. There are challenges to the theory, the most outspoken of which comes from religious fundamentalist quarters. In order to keep that opposition at bay, there appears to have developed a natural solidarity among the scientific community not to question too much about the theory, lest that questioning gets picked up and used by those who reject the theory out rightly. Alternatively, fundamentalist challenges, have distracted the scientific community from refining the theory. There is always the risk, of course, that anyone posing challenging questions to the theory's general orthodoxies, will be labelled a "crackpot", and lumped in with the fundamentalists, something which I have been suspected of in another thread on a similar issue by an ungracious member. Not to worry, I've long given up the idea we live in a just and reasonable world, those concepts being an abstraction, leaving me with the dilemma of deciding whether the abstraction is real or its quite imperfect reflection, as experienced in human affairs.

[Swift]

That's as may be; this really isn't the place for just giving lessons. They're generally to be an answer to things.

I am a junior member and haven't been here for too long. Yet pretty much every day I read posts (sometimes from old-timers) that use one of the misconceptions.

I would suggest the place to point them out would be in the thread where the misunderstanding occurs.

Junior, Order Of Kilopi, it means nothing here. The only thing you can take away from a high status group is that the poster in question has managed to stay unbanned for a big number of posts.

OK, enough self-moderation and enough meta-discussion.

First, I have no problem with uwbrother's "lesson" in evolution. It is completely appropriate for the Science & Technology forum. If you are not interested in the lesson (I wouldn't have used that term), then don't participate in the thread. But the sharing of knowledge about science is a primary function of this forum.

Second, particularly the experienced members should know that if you do not think someone's thread or post is appropriate, comments in thread to that effect are not the appropriate mechanism; please use the Report Post function by clicking on the black triangle with the ! in it, in the lower left corner of the post.

Please, let's stick with talking about evolution. Thank you.

[Gillianren]

I have no problem with a "theory of evolution", provided the idea of theory is not lost sight of.

You mean that it's the strongest word in science and evolution is considered to be one of the strongest theories in science?

[tashirosgt]

"Survival of the fittest" is very appropriate

I think "survival of the fittest" is merely another way of saying "survival of the survivors". Whoever survives is, by definition, "fittest". There is no other criterion for being "fittest" than surviving.

[baric]

[*]Evolution is anything but efficient - Male nipples, enough said.

I would like to comment on this. There is no reason to think that male nipples are inefficient.

You have to remember that evolution occurs on a genetic level and nipples (male & female) are a morphological expression of certain genes.

Since male & female humans share the vast majority of their genes, it could actually be LESS efficient for the common human gene pool to maintain separate sets of "nipple genes" since that would require additional male/female variation to be encoded on the genome.

Since there is no reproductive downside to men having nipples, there's no selective pressure to alter genes.

[mike alexander]

I think "survival of the fittest" is merely another way of saying "survival of the survivors". Whoever survives is, by definition, "fittest". There is no other criterion for being "fittest" than surviving.

Use 'Differential reproductive success' instead.

And remember that survival always contains a strong thread of luck.

[Nereid]

I think "survival of the fittest" is merely another way of saying "survival of the survivors". Whoever survives is, by definition, "fittest". There is no other criterion for being "fittest" than surviving.

Actually, mere survival is not enough ... you have to reproduce, and your offspring (or whatever word you choose to use) have to both survive and reproduce too. The concept gets a little blurry for social species like ants - only the queen survives, in an evolutionary sense.

[Robert Tulip]

There is no "end goal"... You do not 'un-evolve'... "Most evolved" or "highly evolved" does not mean "complex"... Natural selection is not random... It's too early to know whether intelligence and body design that leads to technological advancement is a successful adaptation. Humans may well not only go extinct themselves, but cause a massive extinction due to their actions. If so, then at least on our planet this level of intelligence would turn out to be a poor adaptation that got wiped out by natural selection.

Use 'Differential reproductive success' instead. And remember that survival always contains a strong thread of luck.

Evolution involves a progress towards complexity through cumulative adaptation to the environmental niche of life. The differential reproductive success of evolution is directional, towards complex adaptation.

Gradual reversal of entropy caused by growth of complexity and adaptivity is eventually reversed by collapse to a new simpler state of life. Human life could continue to grow more complex for thousands and millions of years. Alternatively, life on earth could collapse into a new simplicity, like the previous planetary extinction events.

Alongside the 'strong thread of luck', in Mike Alexander's phrase, strategies for evolution involve a determination to succeed. For a philosophy of evolution, this determination to reproduce would seem to engage with the ethical material of purpose and meaning, both for humans and for animals. An area of uncertainty in the theory of evolution is the role of free choice and moral responsibility in determining effective survival strategies.

Traditionally, science rejects teleology in the theory of evolution. This is partly because seeing an ethical dimension of evolution opens unsolvable questions of whether we see intrinsic purpose in the universe. It is nevertheless an interesting question whether the theory of evolution, applied to both human and animal situations, raises the need for each organism to see an intrinsic purpose in nature in terms of its own flourishing.

[Nereid]

Evolution involves a progress towards complexity through cumulative adaptation to the environmental niche of life. The differential reproductive success of evolution is directional, towards complex adaptation.

This might be true of the Eukarya, but it is clearly not true of the Bacteria or Archaea.

And even in the Eukarya there are exceptions; most parasites, for example, are driven by differential reproductive success towards much simpler adaptations.

Of course, you may be using "complex adaptation" is a sense different from that I have interpreted ...

[...]

Alongside the 'strong thread of luck', in Mike Alexander's phrase, strategies for evolution involve a determination to succeed. For a philosophy of evolution, this determination to reproduce would seem to engage with the ethical material of purpose and meaning, both for humans and for animals. [...]

Um, I hate to break this to you, but Homo sapiens belongs to kingdom Animalia

[transreality]

Another misconception that is common is 'human' evolution or any other species evolution, is an on-going process of refinement. In actual fact the whole mechanism is just churning over in neutral... in general species do not evolve... but they do give rise to other species through the process of speciation. During this process, the tiny sub-population that becomes the progenitor of the new species evolves rapidly. The whole evolutionary mechanism in general is just spinning in neutral and only comes into any effect only while that speciation process is occurring, in a small window of time, and to a very small subset of individuals from the the parent species.

[Robert Tulip]

This might be true of the Eukarya, but it is clearly not true of the Bacteria or Archaea.

And even in the Eukarya there are exceptions; most parasites, for example, are driven by differential reproductive success towards much simpler adaptations.

Of course, you may be using "complex adaptation" is a sense different from that I have interpreted ...


Um, I hate to break this to you, but Homo sapiens belongs to kingdom Animalia

Fair enough, I was thinking of ecosystems as a whole in saying evolution increases complexity. Sure, bacteria find a simple body plan and stick to it. But they live on a planet dominated by macroscopic life, where the trend of an undisturbed system, eg a rainforest or a coral reef, is towards continually increasing complexity, as organisms find new and better ways to compete and cooperate. Building on precedent, the whole system gets steadily more complex and adaptive until an external disruption occurs. This pattern can be seen in all geological periods since the Cambrian.

Point taken on animalia, it is simply that we conventionally restrict ethics to human life as distinct from animal life. I would argue there is a directionality, a will if you like, in all complex life. Will is a main factor in evolution. Nature selects for strong will, especially in sexual selection. Will is an intrinsically ethical quality that is produced by evolutionary selection in all complex life, crossing the artificial human-animal barrier.

[Nereid]

Fair enough, I was thinking of ecosystems as a whole in saying evolution increases complexity. Sure, bacteria find a simple body plan and stick to it. But they live on a planet dominated by macroscopic life, where the trend of an undisturbed system, eg a rainforest or a coral reef, is towards continually increasing complexity, as organisms find new and better ways to compete and cooperate. Building on precedent, the whole system gets steadily more complex and adaptive until an external disruption occurs. This pattern can be seen in all geological periods since the Cambrian.

Point taken on animalia, it is simply that we conventionally restrict ethics to human life as distinct from animal life. I would argue there is a directionality, a will if you like, in all complex life. Will is a main factor in evolution. Nature selects for strong will, especially in sexual selection. Will is an intrinsically ethical quality that is produced by evolutionary selection in all complex life, crossing the artificial human-animal barrier.

But they [bacteria] live on a planet dominated by macroscopic life

Not so. The Age of Bacteria began ~3+ billion years ago, and no change has happened since.

Not only do bacteria comprise the bulk of the Earth's biomass (especially if it turns out they are common in the Earth's lithosphere, down to a depth of ~20+ km), but they likely win in the diversity stakes too (no one really knows yet, partly because we have only the sketchiest view of how many bacterial species there are which do not culture).

Further, all (almost all?) eukaryotes rely completely on bacteria (and, perhaps, some archaea too) for their very existence: think of gut flora, nitrogen fixing, decomposition of dead eukaryotes, ...

I would argue there is a directionality, a will if you like, in all complex life

I guess we need to be clear that we're using "complex life" in the same way, but what's the directionality in Plantea species? Fungi species? Rhodophyta species? Heterokontophyta species?

Nature selects for strong will, especially in sexual selection

How does Nature select for strong will in organisms which reproduce asexuallly?

[Strange]

I would argue there is a directionality, a will if you like, in all complex life. Will is a main factor in evolution. Nature selects for strong will, especially in sexual selection.

I suppose you could say that bacteria that made no attempt to move away from a toxic environment or towards food, would not survive. But that is what natural selection is all about. To use the term "will" to describe this is misleading and leads to...

Will is an intrinsically ethical quality

... this sort of confusion of the forces of natural selection with ethics, which are a purely human invention.

To think of the "struggle for survival" in terms of human ambition or desire is as misleading as the misuse of "survival of the fittest" to define a management strategy.

[Robert Tulip]

But they [bacteria] live on a planet dominated by macroscopic life

Not so. The Age of Bacteria began ~3+ billion years ago, and no change has happened since.

Not only do bacteria comprise the bulk of the Earth's biomass (especially if it turns out they are common in the Earth's lithosphere, down to a depth of ~20+ km), but they likely win in the diversity stakes too (no one really knows yet, partly because we have only the sketchiest view of how many bacterial species there are which do not culture).

Further, all (almost all?) eukaryotes rely completely on bacteria (and, perhaps, some archaea too) for their very existence: think of gut flora, nitrogen fixing, decomposition of dead eukaryotes, ...

I would argue there is a directionality, a will if you like, in all complex life

I guess we need to be clear that we're using "complex life" in the same way, but what's the directionality in Plantea species? Fungi species? Rhodophyta species? Heterokontophyta species?

Nature selects for strong will, especially in sexual selection

How does Nature select for strong will in organisms which reproduce asexuallly?

Life on earth was microbial for over three billion years until the Cambrian explosion, so you have a fair point that microbes are the dominant form of life. However, more recent geological periods are marked by the change of organisms with sexual reproduction, so it is reasonable to focus questions about evolution on the most complex and rapidly changing part of the biosphere.

Yes, macrobial life depends on microbes which stay the same for a long time. It is the organisms that change that are of most interest in terms of evolution.

Macrobes are more complex than microbes. A big part of this complexity is the emergence of sexual selection. We see this in flowers being more complex than ferns, and in humans being more complex than viruses. The more complex, the more need for will, eg in walruses competing for the harem.

It may be un-PC to regard humans as the apex of planetary evolution, but the evolution of language and abstract thought is qualitatively more complex than anything else yet found.