A direction to evolution

Discussions on general biology and biological evolution, genetics, zoology, ecology, botany, etc.

A direction to evolution

Postby hyksos on July 11th, 2018, 5:00 pm 

In academic settings , the discipline of Biology is silent about the issue of evolution by natural selection having a direction towards any future destination. That is, it does not suggest there is a direction, nor does it outright deny the existence of it.

  • The orthodox Darwinian theory of natural selection only predicts that speciation will happen, and nothing more.
  • Universities of the 21st century still define "evolution" as a quote, "Changes in allele frequencies".

Does evolution have a larger and broader direction to it? Perhaps evolution slowly gives rise to "higher levels of conscious awareness" or some such.

Your thoughts?
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Re: A direction to evolution

Postby wolfhnd on July 11th, 2018, 5:26 pm 

The universe seems to evolve more complex elements starting with hydrogen and producing heavier elements as stars over a certain mass threshold produce carbon, nitrogen, oxygen and lots of heavier elements. Chaos seems to produce complexity which seems to be a rule you could apply to biology.

The relationship between complexity and consciousness is not clear.
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Re: A direction to evolution

Postby Serpent on July 11th, 2018, 6:21 pm 

hyksos » July 11th, 2018, 4:00 pm wrote:... Biology ....does not suggest there is a direction, nor does it outright deny the existence of it.

That would be because biological specimens can only show what they are made of, from which biologists may infer how they became what they are - their past. There is nothing available to biologists to illustrate or demonstrate a purpose or destination of a specimen - its genetic future.
Yes, evolution has produced increasingly complex organisms over time, but many complex organisms have also become extinct over the same period, while many simpler ones have persisted for billions of years, virtually unchanged.
All we can surmise from this is that if and when environmental conditions change, organisms live or die according to their adaptability.

Does evolution have a larger and broader direction to it?

There is no way to tell from inside a process what that process is intended/expected, ultimately, to produce, or whether there is an intender/expector outside the process. That question is beyond the purview of biology or any other science - or, indeed, any component of the ongoing process.
But Physics may contain a hint: entropy. Heat is lost, order breaks down, processes run down and stop.

If you consider that evolution - and for that matter, all of biology - is a byproduct of the physical universe that only comprises a minuscule fraction of the matter in the universe and that complex biological processes only comprise a minuscule fraction of the activities of the universe, it seems unlikely that the fate of biological entities is central to the function or purpose (if any) of the universe.
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Re: A direction to evolution

Postby BadgerJelly on July 12th, 2018, 3:51 am 

Well ... I may start spamming a little about Schiller across this site so may as well start here:

However emphatically and frequently nature might impress itself upon our organs, all nature’s variety is lost upon us because we seek in it only what we have already placed there, because we do not allow it to move into us, but instead thrust ourselves upon it, employing an impatient and interfering reason. If centuries later someone comes along whose sense are calm, innocent and open, and so stumbles on a quantity of phenomena that our prejudice has caused us to ignore, then we are amazed that so many eyes could in broad daylight have missed so much. This premature striving for harmony before one has registered the individual tones from which it is made, the monstrous usurpation by the power of thought of a domain that it in no respect commands, is the reason that so many thinkers fail to further the best of science, and it is hard to say which has harmed the extension of knowledge the more: a faculty of sense lacking form, or a faculty of reason that cannot wait for content.

Friedrich Schiller - On the Aesthetic Education of Man, Thirteenth letter (footnote)


Funnily enough this “letter” seems to have more words in the footnotes than in the main text. A sign that he was digging deep here.

Hope you can see the relevance to the thread.
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Re: A direction to evolution

Postby Forest_Dump on July 12th, 2018, 8:02 am 

I suppose following from that, I do follow Dennett, Dawkins and others when I see it as a matter of perspective. The hugely overwhelming majority of individual organisms are single cell creatures that breed asexuallyrics and therefore are all unique species since they do not really constitute populations that interbreed, share genetic material, etc. There is some variation in how they move about, gather or produce food, etc., but not much. A very tiny minority have gotten more complex through time but not many and most may well have also taken a step back although there is not much back they could go. But if we were to do an unbiased random sampling of individuals/species through time we would find that virtually all were extremely simple and stayed that with no direction towards greater complexity. Nonetheless, a tiny, tiny fraction of a fraction did manage to evolve towards greater complexity with an even smaller percentage producing sexuality and some of them, again a negligible fraction, becoming sentient and marvelling about our luck and coming to the conclusion that it must have been meant to be. Kind of like being born a billionaire and thus concluding you must be special and it was all meant to be that way.
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Re: A direction to evolution

Postby Braininvat on July 12th, 2018, 9:16 am 

AKA "observer selection. "

If there were a direction to evolution, sharks didn't get the memo on that.
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Re: A direction to evolution

Postby Serpent on July 12th, 2018, 9:55 am 

It's not about the algae, nematodes and sharks -- it's all about me!
All those improbable, serendipitous events since the Big Bang were leading up to me.
(and I've left no progeny, so it's all been wasted)
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Re: A direction to evolution

Postby SciameriKen on July 12th, 2018, 10:09 am 

If you want to argue from a scio-religious perspective that evolution is God's tool then I suppose you could say there was a direction to evolution - and that no further evolution will occur in humans (since we are in God's image) -- of course, maybe we haven't reached God's image yet - so I take that back!

From a scientific perspective to put any claim of a direction to evolution would be our arbitrary assessment of ranking organisms as more advanced than others. Although this is useful for humanity's purposes, nature does not care.
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Re: A direction to evolution

Postby Serpent on July 12th, 2018, 10:16 am 

Nature perfected the ant. After that, it was all just bells and whistles.
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Re: A direction to evolution

Postby SciameriKen on July 12th, 2018, 10:46 am 

Serpent » Thu Jul 12, 2018 2:16 pm wrote:Nature perfected the ant. After that, it was all just bells and whistles.


Not sure about that -- the cockroach seems fairly well built!
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Re: A direction to evolution

Postby Serpent on July 12th, 2018, 11:42 am 

This is weirdly reminiscent of a game the men in Corner Gashttps://www.youtube.com/watch?v=Veu-Cm7aHMw play.
In the epic Final Battle, ants vs roaches, who will win?
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Re: A direction to evolution

Postby Braininvat on July 12th, 2018, 12:07 pm 

SciameriKen » July 12th, 2018, 7:46 am wrote:
Serpent » Thu Jul 12, 2018 2:16 pm wrote:Nature perfected the ant. After that, it was all just bells and whistles.


Not sure about that -- the cockroach seems fairly well built!


Yes, but the roaches do not comprise 15-20% of the total biomass of living creatures on Earth. Last I heard, ants do. Which is sort of disturbing. In terms of poundage, ants are the Earth's dominant species.
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Re: A direction to evolution

Postby Braininvat on July 12th, 2018, 12:12 pm 

Serpent » July 12th, 2018, 6:55 am wrote:It's not about the algae, nematodes and sharks -- it's all about me!
All those improbable, serendipitous events since the Big Bang were leading up to me.
(and I've left no progeny, so it's all been wasted)


You selfish bastard! Good god, man, don't you realize how badly we need little Serpent Juniors with their high-functioning brains? And their ability to estivate should come in handy.
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Re: A direction to evolution

Postby Serpent on July 12th, 2018, 12:50 pm 

Braininvat » July 12th, 2018, 11:12 am wrote:You selfish bastard! Good god, man, don't you realize how badly we need little Serpent Juniors with their high-functioning brains?

We haven't fared so well in the last 6000 years. Should have hibernated over this whole sordid bit of history. What we really should have done, of course, was refrain from engagement with the bald monkeys in that walled garden. It's just... they were so pathetically self-important, we thought enlightenment would be an improvement. And I can't even perform a face-palm!

As for the ants, I'm completely in awe of them. Besides co-operation and diversity, what they do really well is fit into whatever conditions and environments they find. They'll only increase, too, as humans eradicate other insect species; they'll keep filling vacant niches and adapting to take advantage of ecological changes. They have always had a part in plant pollination and have already begun taking over from honeybees and butterflies. They build up tolerance for insecticide faster than cockroaches and multiply more efficiently.
(They might even end up inadvertently saving our food crops.)
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Re: A direction to evolution

Postby SciameriKen on July 12th, 2018, 1:33 pm 

Braininvat » Thu Jul 12, 2018 4:07 pm wrote:
SciameriKen » July 12th, 2018, 7:46 am wrote:
Serpent » Thu Jul 12, 2018 2:16 pm wrote:Nature perfected the ant. After that, it was all just bells and whistles.


Not sure about that -- the cockroach seems fairly well built!


Yes, but the roaches do not comprise 15-20% of the total biomass of living creatures on Earth. Last I heard, ants do. Which is sort of disturbing. In terms of poundage, ants are the Earth's dominant species.



From what I'm reading -- thanks to Humans, Cows are the #1 in terms of Biomass:
http://www.sciencefocus.com/qa/what-ani ... mass-earth
listed at about 600 billion KG compared to about 40 billion KG for ants (https://www.bbc.com/news/magazine-29281253)
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Re: A direction to evolution

Postby Braininvat on July 12th, 2018, 1:45 pm 

Yes, I should have clarified that the entire genus of ant (thousand of species) is the largest in biomass. I meant "species" plural, but the word seems to be both singular and plural. If you go by individual species, then yes, it would be larger mammals like those your article mentions. Like those bald monkeys Serpent shouldn't have engaged with.
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Re: A direction to evolution

Postby wolfhnd on July 12th, 2018, 2:43 pm 

In the case of sharks and other creatures mentioned evolution is taking place at a very slow rate. The direction is hidden to some degree or static so they fall outside the scope of the discussion. In the analogy to stars it's only the less stable stars that produce heavy elements. The less massive stars "evolve" slower.

Evolution is not constant nor universal. It's rate and direction varies across species. If it isn't happening then it doesn't exist within that specific context.

Conflating purpose and direction does injustice to the original question. A more productive avenue of discussion may be the relationship between entropy and complexity.
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Re: A direction to evolution

Postby Serpent on July 12th, 2018, 6:28 pm 

wolfhnd » July 12th, 2018, 1:43 pm wrote:Conflating purpose and direction does injustice to the original question.

Maybe so, but in cases like this, doesn't direction at least imply, if not require, a destination? The east-west or left-right or up-down kind of direction isn't necessarily purposeful, but to determine the direction of a process, don't you have to assume a starting-point and and an end-point? It's hard to consider destination without purpose.
A more productive avenue of discussion may be the relationship between entropy and complexity.

Yes, it might. If we were in a position to know at what level of complexity systems must begin to break down and what stage of complexity we are currently observing. We can't even know the scale on which the cycle takes place, and whether the evolution of life on this planet plays any significant part in the larger system, or it's just the fuzz on a peach among the fifteen tons of peaches going into the Big Juicer.
It's only because of all these unknowns that I have not taken the topic too seriously.
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Re: A direction to evolution

Postby wolfhnd on July 12th, 2018, 7:12 pm 

Humans assign purpose and direction because life must move forward. Even singled celled organisms move toward nutrients and away from toxins. In this sense direction is a property of life.

As humans we are accustomed to top down design making bottom up design seems unnatural. In bottom up design evolution doesn't need to know where it started or where it is going but a human designer requires an understanding of what is and what can be.
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Re: A direction to evolution

Postby mitchellmckain on July 12th, 2018, 9:02 pm 

The only direction aspect of the process is survival. But the requirements of survival is dictated by the environment, and as the environment changes so does the implied direction of development. These changes depend on numerous internal and external events. Since the process of evolution is not all that deterministic, not even the internal events are all that predictable. Furthermore, if environment is sufficiently favorable then this survival direction is a weak one, and the process of evolution produces considerable diversity. In other words, instead of a single direction their are many. In conclusion, the idea that evolution has some inherent direction or ultimate goal built into it, is unsupportable.
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Re: A direction to evolution

Postby Serpent on July 12th, 2018, 9:27 pm 

wolfhnd » July 12th, 2018, 6:12 pm wrote:Humans assign purpose and direction because life must move forward.

No, that's not movement; that's just time passing and processes taking place.
Even singled celled organisms move toward nutrients and away from toxins. In this sense direction is a property of life.

Yes, that is purposeful motion. But it's omnidirectional: "forward" changes all the time, depending on where the front is pointing. Organisms move this way when it's too cold; that way when they smell food, back the other way when there is a predator, upward to light, downward to safety, hither-and-yon in search of mating opportunities.
Processes are unidirectional and their progress is measured in changes from one state to another. What happens there isn't movement; it has no physical direction, only start- and end-points - and in life-processes, even those are arbitrarily designated (marked out along an uninterrupted chain of chemical reactions) by humans with an anthropocentric perspective.
When we use the word "direction" for a process, it's usually because we know its start and finish; we know the changes that must take place in order to turn x into y. The baking process is supposed to turn a lump of blubbery beige dough into a loaf of golden crusty bread. We know that this process is irreversible. But, in reality, the process didn't start when we popped the pan into the oven; nor does it end when we take the pan out - these are the arbitrary defining moments of an arbitrarily selected portion of all the processes wheat and yeast had already gone through before their encounter with a human, and will continue to go through whatever happens next. "It" doesn't have a direction: we give it a direction that fits our purpose.


As humans we are accustomed to top down design making bottom up design seems unnatural.

Not so much unnatural as a contradiction in terms. That's what makes the OP question misleading.
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Re: A direction to evolution

Postby wolfhnd on July 12th, 2018, 9:43 pm 

Why do people confuse direction with goal or purpose. Hydrogen makes up 75 percent of normal matter but no one would argue that this fact has anything to do with stellar evolution. The hydrogen not in heavy stars is not part of the evolution of more complex elements. Similarly life not in an environment that rewards evolution is not evolving. Where we have observed evolution it typically increases complexity but not always. Does that mean that a shark is less evolved than a human? It depends on what you mean by evolved.

In evolution fitness is everything but again fitness can be measured in various time frames. Technically fitness is simply a count of offspring whether the species is undergoing evolution or not. Is that the number of offspring over the past million years or 10 million years into the future. You can't make these judgments without an inappropriate value system so for the purposes of this discussion the mechanisms of evolution can be put aside and only the static at this moment conditions need apply.
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Re: A direction to evolution

Postby wolfhnd on July 12th, 2018, 9:54 pm 

Serpent your are getting a bit to literally. The analogy was to moving forward towards nutrients and away from toxic waste.

I keep thinking that information theory is the key to unlocking these questions. Some people like to call it a mathematical universe. In any case simple autamata always produce increasingly complex patterns.
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Re: A direction to evolution

Postby Serpent on July 13th, 2018, 12:01 am 

wolfhnd » July 12th, 2018, 8:54 pm wrote:Serpent your are getting a bit to literally. The analogy was to moving forward towards nutrients and away from toxic waste.

Yes, I understand that. But I believe it's important, on this topic, to be very precise in our choice of words.
- Living things move. They move with purpose, in a definite direction, for a particular reason. In this context, "forward" is defined by intention.
- Time and change proceed 'forward', which, in this context, means that they have only one 'direction': the processes are irreversible and without intelligent purpose. In this context, 'direction' is used metaphorically, because there is neither motion nor volition involved.
It is the the metaphorical reference to "movement" and "direction" that give rise to misinterpretation. If we begin with non-literal terms [each of which carries an unstated load of assumption and association], and then allow even a little bit of leeway for subjective interpretation [more assumptions], we very quickly go off the rails into fantasy or superstition or poetry. All those things are nice, but incompatible with science.

I keep thinking that information theory is the key to unlocking these questions.

I don't know anything about information theory. I do think, though, that any scientific question must be couched in precise, unambiguous and accurate terms before they can be answered appropriately.

In any case simple autamata always produce increasingly complex patterns.

Do they?! I had no idea. Examples would be appreciated.

Similarly life not in an environment that rewards evolution is not evolving.

Well, sure. Fitness doesn't just mean having more offspring than a competitor: it means having more offspring survive and succeed. This fitness is like that of a shoe: both are fine workmanship, but only one is the right shape for my foot: it's being better suited to the particular environment.
Where we have observed evolution it typically increases complexity but not always.

As Forest_Dump pointed out a while back, only in a small percentage of cases. Increased complexity is not typical: it's an unusual response to extreme stress. The majority of species subjected to extreme stress die out; only a few have the potential extra level of complexity [in some particular organ, appendage or metabolic adaptation] which allows them to surmount the difficulty.
The ideal circumstance of long survival is stability: a balance of capabilities and environmental conditions.

Does that mean that a shark is less evolved than a human?

Not at all! All species alive at the same time are evolved to the exact same degree. The only way one can compare milestones of evolution is in the time-line.

It depends on what you mean by evolved.

In science, the word must have a single, objective definition, like
Evolution is a process of gradual change that takes place over many generations, during which species of animals, plants, or insects slowly change some of their physical characteristics.
Otherwise, we don't know what we're talking about.
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Re: A direction to evolution

Postby wolfhnd on July 13th, 2018, 2:36 am 

Where is Hyksos

We have made some progress in defining the terms.

The only problem I have so far is with people pointing out that only a small percentage of species are actively evolving. To which I say well then that isn't evolution is it?
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Re: A direction to evolution

Postby Serpent on July 13th, 2018, 9:40 am 

wolfhnd » July 13th, 2018, 1:36 am wrote:The only problem I have so far is with people pointing out that only a small percentage of species are actively evolving. To which I say well then that isn't evolution is it?

Evolution is life-forms changing in response to change.
Any species that changes over the generations to fit better into its environment is evolving. Even sharks and ants change in some minute ways to take advantage of new factors (like pirates' victims as a food source) or protect themselves from new dangers in their environment (like insecticide) - but they're well enough suited that they don't need to change in any dramatic way - not so's we would notice. Many algae, mollusks and fungi haven't changed for billions of of years: they evolved as far as they needed to, and will evolve some more, if and when they need to.

It is a common misunderstanding to equate evolution with increased complexity. That's not science, that's a egocentric fallacy. We start from the [often unstated] assumption that we are the pinnacle of creation, and so all of evolution must have been directed at creating us, and so all stages of evolution are measured in terms of how nearly human. That makes an alga (so perfectly adapted and efficient that it can fill your whole pond in one summer) "low" on the evolutionary scale, because it's only 1% human. A shark - also extremely fit for its lifestyle - is primitive, but has organs like ours, so it's 20% human and thus higher on the anthropocentric evolutionary scale; a gorilla (even though it's so maladapted to the human-dominated world that there are only about 14 left) looks like us and acts like us, so it's 90% human and very "high" the anthropocentric evolutionary scale.

Nature doesn't use a scale. There is no high and low. There is only ability to continue.
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Re: A direction to evolution

Postby mitchellmckain on July 13th, 2018, 12:35 pm 

Braininvat » July 12th, 2018, 12:45 pm wrote:Yes, I should have clarified that the entire genus of ant (thousand of species) is the largest in biomass. I meant "species" plural, but the word seems to be both singular and plural. If you go by individual species, then yes, it would be larger mammals like those your article mentions. Like those bald monkeys Serpent shouldn't have engaged with.


According to what I am reading on biomass in Wikipedia, the uncertainty with regards to ants is rather high and the information on termites is completely lacking. But even the highest estimates for ants (100 million tons dry) still puts them lower than both humans (105 million tons dry) and cattle (156 million tons dry). Also you said "total mass of living creatures, but according to what I see, it is 80% plants and and another 15% bacteria leaving only 5% for all the other living organisms on the planet. So perhaps you meant a percentage restricted to animal life?

Personally, I am a bit skeptical of all these percentages without more data on beetles whose species greatly outnumber those of any other animal. Also as I keep looking I am finding a lot of contradictory estimates. In one place, I read that Antarctic krill were about on par with humans for biomass and in another place the estimate had them at 5 times the biomass. Looks to me like people are pushing a lot of speculations and guesses around without enough facts behind them.
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Re: A direction to evolution

Postby wolfhnd on July 13th, 2018, 2:51 pm 

I think the fear of being accused of being anthropocentric is distorting this discussion. No where in the discussion did I suggest that humans were the most "evolved" species. It is in any case irrelevant.

The only thing that needs to be acknowledged is that the organisms that can from the primordial soup had molecular complexity greater than the local environment.

A related topic is if complexity reduces stability. It appears to be a universal rule. As it relates to evolution it has been suggested that this rule is captured by the phrase evolved to evolve. This concept also cause great confusion because it seems to imply design.

The adaptation of pathogens to antibiotics has been studied to determine the adaptive mechanism. It would be tempting to assume that the "better designed" individuals would adapt more efficiently but that is not what we find. What we find is that genetic diversity is lower in populations not stressed by antibiotics. Genetic variation is suppressed by the fact that mutations tend to be out competed. As the population starts to die off a small number of less stable individuals survive increasing genetic diversity because of an increased mutation rate. If this sounds like it contradicts survival of the fittest it is only because the way language is normally used follows different rules.
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Re: A direction to evolution

Postby wolfhnd on July 13th, 2018, 5:03 pm 

Chaos, Complexity, and Entropy A physics talk for non-physicists

https://www.researchgate.net/publicatio ... physicists

The relationship between Chaos, complexity and entropy seem to be key to this discussion. As complexity increases entropy decreases and chaos increases. When an organism dies entropy increases and the molecules it is composed of become less complex.
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Re: A direction to evolution

Postby Serpent on July 13th, 2018, 6:27 pm 

Sorry, accidentally quoted myself when i meant to edit.
Last edited by Serpent on July 13th, 2018, 6:43 pm, edited 1 time in total.
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