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Posted

Natural selection is self evident, there's not a person on the planet who disagrees with it! (if you die, you die! If you don't reproduce, you don't reproduce!)

But how come there seems to be so many people who take this blatantly obvious undeniable fact, and then assert that life is merely about our own survival/reproduction!?

(Just for the record, I'm not denying that life on our planet has developed gradually! The fossil record points to that fairly clearly!)

Posted
1 hour ago, Free_Pepe said:

But how come there seems to be so many people who take this blatantly obvious undeniable fact, and then assert that life is merely about our own survival/reproduction!?

Whilst I won't say I have never met such a person I haven't met many.

What information do you base your statement on ?

It must be clear that unless your statement can be substantiated there is no case to answer M'Lud.

Posted
On 7/25/2020 at 4:22 AM, Free_Pepe said:

Natural selection is self evident, there's not a person on the planet who disagrees with it! (if you die, you die! If you don't reproduce, you don't reproduce!)

But how come there seems to be so many people who take this blatantly obvious undeniable fact, and then assert that life is merely about our own survival/reproduction!?

I can't believe I'm defending an anti-evolution stance, but you're strawmanning their argument. The part they disagree with is natural selection leading to a change in species over time, not that traits are passed along without reproduction. You're making their argument too simple in order to discredit it, and that's using a fallacy to support your own argument.

Most anti-evolution arguments acknowledge what they call "microevolution", where children share traits from their parents. They just don't believe natural selection can account for a complete change in species.

Anybody who is looking only at their own life and reproduction isn't addressing evolutionary concerns. Natural selection is one way to change allele frequencies within a population over time.

Posted

Help me out here because I left school when I was 15 to work in a factory so I had to work things out for myself instead of being told how it is by a teacher or an elder. So my understanding of evolution is that if you pick up ten thousand Africans and drop them in Ireland  where no other humans of any colour exist, then you return 100,000 later the general population would have evolved to Blue eyed blonds because as soon as they hit ground zero they would have realised that the climate was really cold and they should only choose lighter skin mates, and the cold would prevent the darker skin men from reproducing because of the cold and being of a darker complexion they couldn't resource food as well as the lighter skin men who had all the girls and could sneak up to a vegetable without scaring it away. Have I got it right?

12 hours ago, Free_Pepe said:

Natural selection is self evident, there's not a person on the planet who disagrees with it! (if you die, you die! If you don't reproduce, you don't reproduce!)

But how come there seems to be so many people who take this blatantly obvious undeniable fact, and then assert that life is merely about our own survival/reproduction!?

(Just for the record, I'm not denying that life on our planet has developed gradually! The fossil record points to that fairly clearly!)

A giraffe grew a long neck so that it could reach the leafs on the top branches, that is so clever!  

Posted
2 hours ago, Polykephalous said:

So my understanding of evolution is that if you pick up ten thousand Africans and drop them in Ireland  where no other humans of any colour exist, then you return 100,000 later the general population would have evolved to Blue eyed blonds because as soon as they hit ground zero they would have realised that the climate was really cold and they should only choose lighter skin mates, and the cold would prevent the darker skin men from reproducing because of the cold and being of a darker complexion they couldn't resource food as well as the lighter skin men who had all the girls and could sneak up to a vegetable without scaring it away. Have I got it right?

Nope that is not how it would work. For the most part organisms do not know what adaptations are going to work (and even with extensive research it can be difficult to tell). Rather what happens is that the conditions the organisms live in create so-called selective pressures. What it basically means is that certain genetic traits are more likely to reproduce than others. But different pressures can have different strengths. So let's say lack of sunlight is a strong pressure. Also assume that folks with more melanin (i.e. who are darker) produce less vitamin D are are prone to vitamin D deficiency. What fist needs to happen is that there are either already folks with lighter skin in the population or that at some point mutants arise with lighter skin.  Let's further assume that this make folks less likely to reproduce so mutants with less melanin may be more successful in reproduction and over many generations the pool will be dominated by them. However, unless the selection is super strong, there is likely always going to be a mix. 

If a population is relatively homogeneous, more often than not another aspect is important, the so-called bottleneck effect. This is when there is a small starting population where drift can play a large effect, resulting in small population with low genetic diversity. This is one of the reasons why in Africa we have a large genetic variability compared to Europeans. 

On top of it there are other random effects which have nothing to do with geography. For example if a in a population no mutations for blue eyes occur (which is basically traced to a mutation in a single gene), there will never be blue-eyed folks. 

Posted

The kids that didn't get rickets would do better and go on to have more and healthier kids as adults - bigger families - than those that did get rickets. That sounds like natural selection, not sexual selection yet mate selection would be part of it. I'm not sure how obvious any connection with skin colour would be; there will be different susceptibility to deficiency illness according to lifestyle and dietary differences as well.

The more obvious mate selection criteria might be the unattractiveness of bow legged sick youths - choosing for health, not skin colour - but I suppose an enduring mate preference for lighter skins, as a sign of good luck re healthy children could emerge. But then again maybe we get coastal fisherfolk with dark skins and forest hunter gatherers with lighter skins.

Posted
On 7/26/2020 at 1:38 PM, Ken Fabian said:

The kids that didn't get rickets would do better and go on to have more and healthier kids as adults - bigger families - than those that did get rickets. That sounds like natural selection, not sexual selection yet mate selection would be part of it. I'm not sure how obvious any connection with skin colour would be; there will be different susceptibility to deficiency illness according to lifestyle and dietary differences as well.

The more obvious mate selection criteria might be the unattractiveness of bow legged sick youths - choosing for health, not skin colour - but I suppose an enduring mate preference for lighter skins, as a sign of good luck re healthy children could emerge. But then again maybe we get coastal fisherfolk with dark skins and forest hunter gatherers with lighter skins.

So does that mean that any Africans who move to Ireland and don't take vitamins will have a high probability of being afflicted with rickets?  

Posted
22 minutes ago, Polykephalous said:

So does that mean that any Africans who move to Ireland and don't take vitamins will have a high probability of being afflicted with rickets?  

No, it their vitamin D levels are, on average, lower. While this increases risk somewhat, only a small subset actually develop a disease.

Posted

Am I wrong in believing that if a primitive group relocated to another environment that was unpleasant but not deadly, then there would be no need to evolve? Is it more possible that variants of humans originated in different parts of the world and mixed with each other?      

Posted

Evolution is never a need. It is just something that happens if the genetic composition of a group starts changing. This can be due to random events, but also due to selective pressures (i.e. there is different reproductive success). 

With regard to human origins, DNA evidence strongly support divergence from a central group originating in Africa. From there we have multiple waves of migration. Also note that skin colour as  a whole is only a tiny part of our genetic history, it is mostly historical baggage that emphasizes it so much.

Posted
On 7/29/2020 at 3:59 AM, CharonY said:

Evolution is never a need. It is just something that happens if the genetic composition of a group starts changing. This can be due to random events, but also due to selective pressures (i.e. there is different reproductive success). 

With regard to human origins, DNA evidence strongly support divergence from a central group originating in Africa. From there we have multiple waves of migration. Also note that skin colour as  a whole is only a tiny part of our genetic history, it is mostly historical baggage that emphasizes it so much.

I do hope no one was offended by my using skin colour as an example, it wasn't meant as a superior or inferior reference to any race.

Posted
On 7/25/2020 at 11:35 PM, Polykephalous said:

A giraffe grew a long neck so that it could reach the leafs on the top branches, that is so clever!  

In what way was this clever - ie a display of learning something ?

There is another effect, not quite the same as Natural Selection that works like this.

Consider a room where there is an efficient fly killer, that kills and removes flies in range.
Now consider a naturalist who measures the average fly density in that room and in adjoining volumes.

Unsuprisingly he finds that the fly density is lower in the room than elsewhere nearby.
He also notices the lethal killer.
Based on the fly density comparisons he comes to the conclusion that the flies have learned to avoid the danger zone.

Was his conclusion correct ?

Posted
2 hours ago, Polykephalous said:

I do hope no one was offended by my using skin colour as an example, it wasn't meant as a superior or inferior reference to any race.

That's fine, the issue is that one has to be very careful with extrapolating things, especially if the basic assumption is flawed. Such as that evolution only happens under certain challenges.

The reason for being careful is of course that there are certain folks that weaponize such misunderstandings or flawed premises to create narratives that imply inferiority of certain groups.

  • 4 months later...
Posted
On 7/25/2020 at 6:35 PM, Polykephalous said:

Help me out here because I left school when I was 15 to work in a factory so I had to work things out for myself instead of being told how it is by a teacher or an elder. So my understanding of evolution is that if you pick up ten thousand Africans and drop them in Ireland  where no other humans of any colour exist, then you return 100,000 later the general population would have evolved to Blue eyed blonds because as soon as they hit ground zero they would have realised that the climate was really cold and they should only choose lighter skin mates, and the cold would prevent the darker skin men from reproducing because of the cold and being of a darker complexion they couldn't resource food as well as the lighter skin men who had all the girls and could sneak up to a vegetable without scaring it away. Have I got it right?

A giraffe grew a long neck so that it could reach the leafs on the top branches, that is so clever!  

Ok, so what ponders me is, take the statement about the giraffe, if the giraffe came to realize if his neck was longer he could teach the leafs on high branches then what lines of communication were/are used (in natural selection) to ensure that would happen. It's as if the giraffe told something with a working, thinking mind and (it?) came up with the plan to achieve this.

I mean don't anybody wonder this too about natural selection where all adaptations to all species have become so?

Posted
On ‎7‎/‎25‎/‎2020 at 6:35 PM, Polykephalous said:

A giraffe grew a long neck so that it could reach the leafs on the top branches, that is so clever!  

What is NOT clever is the total misunderstanding of evolution, as Studiot also points out.

A giraffe did not 'grow' a long neck in response to the difficulty of reaching the top branches.
What actually happened was that giraffes with slightly longer necks have a favorable advantage to reaching the top branches.
They then do better than the others ( with shorter necks ) at the survival game.
Over time, this environmental forcing results in longer, and longer necks better adapted for survival.
Really not that difficult if you think about it.

Posted
1 hour ago, SerengetiLion said:

Ok, so what ponders me is, take the statement about the giraffe, if the giraffe came to realize if his neck was longer he could teach the leafs on high branches then what lines of communication were/are used (in natural selection) to ensure that would happen. It's as if the giraffe told something with a working, thinking mind and (it?) came up with the plan to achieve this.

I mean don't anybody wonder this too about natural selection where all adaptations to all species have become so?

This is what Lamarck thought. He was wrong; evolution doesn’t work that way.

Posted
On 7/25/2020 at 11:22 AM, Free_Pepe said:

But how come there seems to be so many people who take this blatantly obvious undeniable fact,

I think it is worth noting that until Darwin and Wallace came along natural selection was not a "blatantly obvious undeniable fact". Thomas Huxley,"Darwin's bulldog", a considerable thinker himself, remarked (and I paraphrase this, to save searching for the precise wording) "How silly, I should have thought of that."

On the subject of giraffe necks, I read some research four or five years ago arguing that the long necks were not related to advantages associated with reaching higher foliage. I may be misrembering, but I think the researchers had determined that a) giraffes don't favour the higher foliage, (b) longer necked specimens do not appear to enjoy a reproductive advantage. While searching for a link to the research I found this one: E.M.Williams "Giraffe Stature and Neck Elongation: Vigilance as an Evolutionary Mechanism" Biology 2016, 5(3), 35

Here is the abstract

Giraffe (Giraffa camelopardalis), with their long neck and legs, are unique amongst mammals. How these features evolved is a matter of conjecture. The two leading ideas are the high browse and the sexual-selection hypotheses. While both explain many of the characteristics and the behaviour of giraffe, neither is fully supported by the available evidence. The extended viewing horizon afforded by increased height and a need to maintain horizon vigilance, as a mechanism favouring the evolution of increased height is reviewed. In giraffe, vigilance of predators whilst feeding and drinking are important survival factors, as is the ability to interact with immediate herd members, young and male suitors. The evidence regarding giraffe vigilance behaviour is sparse and suggests that over-vigilance has a negative cost, serving as a distraction to feeding. In woodland savannah, increased height allows giraffe to see further, allowing each giraffe to increase the distance between its neighbours while browsing. Increased height allows the giraffe to see the early approach of predators, as well as bull males. It is postulated that the wider panorama afforded by an increase in height and longer neck has improved survival via allowing giraffe to browse safely over wider areas, decreasing competition within groups and with other herbivores

Posted
46 minutes ago, MigL said:

What is NOT clever is the total misunderstanding of evolution, as Studiot also points out.

A giraffe did not 'grow' a long neck in response to the difficulty of reaching the top branches.
What actually happened was that giraffes with slightly longer necks have a favorable advantage to reaching the top branches.
They then do better than the others ( with shorter necks ) at the survival game.
Over time, this environmental forcing results in longer, and longer necks better adapted for survival.
Really not that difficult if you think about it.

See you're not getting what I'm saying. The giraffe didn't say, ok neck, grow longer and the next generation said the same. Something is communicated to to achieve these adaptations. I wouldn't think the giraffe had much say in the process or at least not concious of it.

Posted (edited)
3 hours ago, SerengetiLion said:

Ok, so what ponders me is, take the statement about the giraffe, if the giraffe came to realize if his neck was longer he could teach the leafs on high branches then what lines of communication were/are used (in natural selection) to ensure that would happen. It's as if the giraffe told something with a working, thinking mind and (it?) came up with the plan to achieve this.

I mean don't anybody wonder this too about natural selection where all adaptations to all species have become so?

It is very easy to visualize. But it's better to show it with the example of birds and camouflage color.

We have a bird population. They have offspring. Some are whiter than their parents, others are blacker than their parents. If they live on rocks, the more gray-black ones are harder for predators to spot. If they live in cold regions of the Earth, whitish ones are more difficult to see on snow by predators. These more visible are more likely to be a target for predators than those with a better camouflage color as they blend in with the surroundings they live in.

Cells subdivide. DNA splits to two chains, then rebuilds in two new pieces. But unlike people thought couple hundred years ago (mostly religious people), replication is not perfect. There is introduced random error. Radioactive Carbon C-14 is decaying at a random moment (Carbon is part of DNA/RNA/cells in organic compounds, proteins, fats, amino acids etc.), cosmic rays pass through everything and damage (ionize) everything on their path, free radicals are reacting with DNA/RNA/cell compounds and damaging them etc. etc.

Majority of these damages can be fixed. Some are meaningless to living cell and cell survives change. Some are so dramatic that cell is dying. But tiny part of mutations are appropriate and meaningful. Depending where animal is living (e.g. rocks or on snow) random gradual change of gene responsible for coding skin or feather color is accidentally giving better camouflage against predators.

1 hour ago, SerengetiLion said:

See you're not getting what I'm saying. The giraffe didn't say, ok neck, grow longer and the next generation said the same. Something is communicated to to achieve these adaptations. I wouldn't think the giraffe had much say in the process or at least not concious of it.

From time to time, there is created random mutation in which animal is getting yet another vertebrae in the spine. From time to time there is born animal which has LESS vertebrae in the spine than parents.. From time to time there is born animal/human which has one finger more and one finger less than parents. etc. etc. They still could be successful in other alternative environments.

https://en.wikipedia.org/wiki/Polydactyly

"Polydactyly or polydactylism (from Greek πολύς (polys) 'many', and δάκτυλος (daktylos) 'finger'),[1] also known as hyperdactyly, is an anomaly in humans and animals resulting in supernumerary fingers and/or toes.[2] Polydactyly is the opposite of oligodactyly (fewer fingers or toes)."

https://en.wikipedia.org/wiki/Oligodactyly

"Oligodactyly (from the Ancient Greek oligos meaning "few" and δάκτυλος daktylos meaning "finger") is the presence of fewer than five fingers or toes on a hand or foot.[1][2]"

"humans have 33 vertebrae, frogs have 10 or fewer, and snakes can have more than 300."

Males and females of the same specie can have different number of vertebrae.

https://www.researchgate.net/figure/Average-number-of-vertebrae-in-males-and-females-of-27-species-of-caudate-amphibians-and_tbl1_232710526

 

Edited by Sensei
Posted

I have an even more simple example, Sensei ...

Let's say SerengetiLion is ugly as sin, while I am ridiculously good looking.
( I assure you, not far from the truth 😁 )
I have access to many more females than he does, and father 8 boys to his two.
Let's say we pass on our ugly/beautiful genes to our kids, and the same thing eventually happens to them.
After two generations there are 64 of my beautiful boys and four of his ugly ones.
After three generations 512 beautiful boys and only 8 ugly ones.
The exponential growth of beautiful kids far outpaces the growth of ugly kids, until another environmental factor becomes active; the supply of available females diminish, until all the ones available choose beautiful boys as partners, and there are none left to reproduce with the ugly boys, who can no longer pass on their genes.
The ugly boys then go extinct.

1 hour ago, SerengetiLion said:

Something is communicated to to achieve these adaptations.

What exactly, do you think needs to be communicated to achieve this ?
And to whom ?

Posted
35 minutes ago, MigL said:

I have an even more simple example, Sensei ...

Let's say SerengetiLion is ugly as sin, while I am ridiculously good looking.
( I assure you, not far from the truth 😁 )
I have access to many more females than he does, and father 8 boys to his two.
Let's say we pass on our ugly/beautiful genes to our kids, and the same thing eventually happens to them.
After two generations there are 64 of my beautiful boys and four of his ugly ones.
After three generations 512 beautiful boys and only 8 ugly ones.
The exponential growth of beautiful kids far outpaces the growth of ugly kids, until another environmental factor becomes active; the supply of available females diminish, until all the ones available choose beautiful boys as partners, and there are none left to reproduce with the ugly boys, who can no longer pass on their genes.
The ugly boys then go extinct.

What exactly, do you think needs to be communicated to achieve this ?
And to whom ?

First let's get one thing straight

35 minutes ago, MigL said:

I have an even more simple example, Sensei ...

Let's say SerengetiLion is ugly as sin, while I am ridiculously good looking.
( I assure you, not far from the truth 😁 )
I have access to many more females than he does, and father 8 boys to his two.
Let's say we pass on our ugly/beautiful genes to our kids, and the same thing eventually happens to them.
After two generations there are 64 of my beautiful boys and four of his ugly ones.
After three generations 512 beautiful boys and only 8 ugly ones.
The exponential growth of beautiful kids far outpaces the growth of ugly kids, until another environmental factor becomes active; the supply of available females diminish, until all the ones available choose beautiful boys as partners, and there are none left to reproduce with the ugly boys, who can no longer pass on their genes.
The ugly boys then go extinct.

What exactly, do you think needs to be communicated to achieve this ?
And to whom ?

First off, you need not assume I'm a "he" because I'm not. 

We can get into all sorts of examples for you to understand what I was asking. But since nobody knows what's communicated as far as all adaptations of all species and to "whom" then I have no choice but to keep wondering.

Posted (edited)
1 hour ago, SerengetiLion said:

First off, you need not assume I'm a "he" because I'm not. 

Makes no difference to an EXAMPLE.
For all you know, I'm female; how is this pertinent to the argument ?

 

1 hour ago, SerengetiLion said:

But since nobody knows what's communicated as far as all adaptations of all species and to "whom" then I have no choice but to keep wondering.

Sure; nobody knows what's communicated.
Nobody knows what is paid.
Nobody knows what's learned.
Nobody knows what's stolen.
Or knows what's real.
Or what's true.
Etc. Etc. Etc.

None of those statements make any sense.
I guess you have no choice but to keep wondering.

 

Or are you merely asking how dominant genes are passed on to the next generation ??

Edited by MigL

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