The case for Evolution

[ASHES]

I tried this before, it didn't work. I even used pictures and diagrams and charts, yet hundreds of pages later, "but bananas!"

 

[MamboDervish]

“Every living thing is a masterpiece, written by nature and edited by evolution.”
― Neil deGrasse Tyson

Evidence Supporting Biological Evolution

Along path leads from the origins of primitive "life," which existed at least 3.5 billion years ago, to the profusion and diversity of life that exists today. This path is best understood as a product of evolution.
Contrary to popular opinion, neither the term nor the idea of biological evolution began with Charles Darwin and his foremost work, On the Origin of Species by Means of Natural Selection (1859). Many scholars from the ancient Greek philosophers on had inferred that similar species were descended from a common ancestor. The word "evolution" first appeared in the English language in 1647 in a nonbiological connection, and it became widely used in English for all sorts of progressions from simpler beginnings. The term Darwin most often used to refer to biological evolution was "descent with modification," which remains a good brief definition of the process today. Darwin proposed that evolution could be explained by the differential survival of organisms following their naturally occurring variation—a process he termed "natural selection." According to this view, the offspring of organisms differ from one another and from their parents in ways that are heritable—that is, they can pass on the differences genetically to their own offspring. Furthermore, organisms in nature typically produce more offspring than can survive and reproduce given the constraints of food, space, and other environmental resources. If a particular off-spring has traits that give it an advantage in a particular environment, that organism will be more likely to survive and pass on those traits. As differences accumulate over generations, populations of organisms diverge from their ancestors.

--Continued...

... and continued ... and continued .... and continued.

Well intentioned but, at least in part, casting pearls before swine.
Those who most need to read and grasp what you have presented will not, and those who already fully grasp these concepts need not.
Kudos at least for posting it under a correct forum.

 

[NatMorton]

At this point, why does anyone feel this "case" needs to be made? The case for evolution is already overwhelming. Those arguing against it are almost exclusively doing so out of religious zeal, and as such no volume of evidence or reasoning is ever going to move them.

 

[Gordy327]

At this point, why does anyone feel this "case" needs to be made? The case for evolution is already overwhelming.

There is still a significant portion of the population who do not understand or accept evolution. So let's consider this a little educational reminder.

Those arguing against it are almost exclusively doing so out of religious zeal, and as such no volume of evidence or reasoning is ever going to move them.

Most likely. But such willful ignorance should always be combated, regardless of some peoples irrationality.

 

[NatMorton]

There is still a significant portion of the population who do not understand or accept evolution. So let's consider this a little educational reminder.

Most likely. But such willful ignorance should always be combated, regardless of some peoples irrationality.

One might as well argue with squid.

 

[OrphanSlug]

I agree with others in that the evidence for the principles and theories of Evolution are well established, and we have every means within systems of process to consistently question and refine our understandings with an ideology of wanting to learn more.

Whatever population still out there believing the world is several thousand years old are our problem.

 

[Gordy327]

One might as well argue with squid.

I often do.

Whatever population still out there believing the world is several thousand years old are our problem.

The best way to deal with that problem is to provide actual scientific information and education to combat such willful ignorance.

 

[Channe79]

I don't accept the idea that the first modern homo sapiens evolved in Africa about 400k year ago and we are all descended from them. There's too much phenotype and biological variances and not enough time for them to have formed that way.

I contend all the homo groups evolved from Homo Antecessor (HA) who left Africa about 1.5 million years ago and spread throughout the world. By around 300k years ago HA had evolved into the nine known homo species that we've accounted for thus far.

From around 300k years to 100k years, we homo sapiens fought with and occasionally mixed with the other eight homo groups - eventually ending all except for the Neanderthals and Homo Floresiensis by around 65k years.
Then, around 65k years ago, it was just us and Homo Floresiensis. Then it was just us homo sapiens for the past 50k years. I do, however, think we sapiens had already evolved into the various phenotypes that still exist today about 50k years ago.

 

[NatMorton]

I don't accept the idea that the first modern homo sapiens evolved in Africa about 400k year ago and we are all descended from them. There's too much phenotype and biological variances and not enough time for them to have formed that way.

I contend all the homo groups evolved from Homo Antecessor (HA) who left Africa about 1.5 million years ago and spread throughout the world. By around 300k years ago HA had evolved into the nine known homo species that we've accounted for thus far.

From around 300k years to 100k years, we homo sapiens fought with and occasionally mixed with the other eight homo groups - eventually ending all except for the Neanderthals and Homo Floresiensis by around 65k years.
Then, around 15000 years ago, it was just us and Homo Floresiensis. Then it was just us homo sapiens for the past 12k years. I do, however, think we sapiens had already evolved into the various phenotypes that still exist today about 50k years ago.

Again, don't have a link handy as the reading I did on this was a long time ago and in book form, but I think the counter argument is that the accumulated DNA differences we see across all humans today does not represent enough accumulated genetic drift for a common ancestor to be older than, say, 120k years. That data refutes the multi-region theory is the primary driver of homo sapien evolution.

 

[NatMorton]

I don't accept the idea that the first modern homo sapiens evolved in Africa about 400k year ago and we are all descended from them. There's too much phenotype and biological variances and not enough time for them to have formed that way.

I contend all the homo groups evolved from Homo Antecessor (HA) who left Africa about 1.5 million years ago and spread throughout the world. By around 300k years ago HA had evolved into the nine known homo species that we've accounted for thus far.

From around 300k years to 100k years, we homo sapiens fought with and occasionally mixed with the other eight homo groups - eventually ending all except for the Neanderthals and Homo Floresiensis by around 65k years.
Then, around 15000 years ago, it was just us and Homo Floresiensis. Then it was just us homo sapiens for the past 12k years. I do, however, think we sapiens had already evolved into the various phenotypes that still exist today about 50k years ago.

And very dated, but this is the sort of thing I was referring to:

As reported in this week's issue of Science, a team led by human population geneticist Li Jin of the University of Texas, Houston, and Fudan University in China took blood samples from 12,127 men in 163 populations in Asia, including China, Southeast Asia, and Siberia. They found that every one had inherited one of three markers indicating that their Y chromosome could be traced to forefathers who lived in Africa in the past 35,000 to 89,000 years. "We came to a simple conclusion," Jin says. "There are no mutations left [from archaic Asians]."

Source: https://www.science.org/content/art...nd that every one,past 35,000 to 89,000 years.

 

[Channe79]

They found that every one had inherited one of three markers indicating that their Y chromosome could be traced to forefathers who lived in Africa in the past 35,000 to 89,000 years. "We came to a simple conclusion," Jin says. "There are no mutations left [from archaic Asians]."

If that's what the science says, I'll accept it.
I just figured it would take more than 89k years to go from this:



to this:



Forget change in skin tone, but also the shape of the face, height, hair changes, etc ...
If you told me 500k years, I could accept it easier.
89k just seems so crazy short.

 

[NatMorton]

If that's what the science says, I'll accept it.
I just figured it would take more than 89k years to go from this:

View attachment 67408210

to this:

View attachment 67408214

Forget change in skin tone, but also the shape of the face, height, hair changes, etc ...
If you told me 500k years, I could accept it easier.
89k just seems so crazy short.

You're letting your eyes fool you. Very small changes in DNA lead to extreme changes in expression.

For example, these two organisms:



and



... have a 99% DNA match. That 1% difference makes all the difference.

 

[Channe79]

You're letting your eyes fool you. Very small changes in DNA lead to extreme changes in expression.

For example, these two organisms:

View attachment 67408231

and

View attachment 67408228

... have a 99% DNA match. That 1% difference makes all the difference.

In what other species do we see such intellectual and physical differences with only 1% of variance ?
The anaconda and python are two different species but look similar. It's always intrigued me how we and chimps are so alike yet so different.

 

[NatMorton]

In what other species do we see such intellectual and physical differences with only 1% of variance ?
The anaconda and python are two different species but look similar. It's always intrigued me how we and chimps are so alike yet so different.

I suspect many, but why do you need more than one example to demonstrate how very little DNA change can generate extreme changes in gene expression?

 

[Gordy327]

In what other species do we see such intellectual and physical differences with only 1% of variance ?
The anaconda and python are two different species but look similar. It's always intrigued me how we and chimps are so alike yet so different.

Organisms that share the same genus, family, ect will be more closely related genetically than Organisms that do not share similar taxonomic lines.

 

[brothern]

In what other species do we see such intellectual and physical differences with only 1% of variance ?
The anaconda and python are two different species but look similar. It's always intrigued me how we and chimps are so alike yet so different.

I suspect many, but why do you need more than one example to demonstrate how very little DNA change can generate extreme changes in gene expression?

The faulty assumption that a lot of people make about DNA is that all of it is functional. I.e., the entire sequence available is referenced by something or codes for something. However that's not the case. In humans the running estimate is that only something like 7-9% of our DNA is functional. The remainder is junk. It does nothing. It just sits there getting dusty.

Couple that faulty assumption with these "X percent is identical" comparisons, and what it seems like what should be the case is a predictable linear scale of difference between species. E.g., a 75% similarity match between two species means that the two organisms should look roughly 75% identical. Or a 99% similarity should result in 99% identical organisms.

But, of course, not the case because ... functionality.

The more apt comparisons would be to (for example) just compare the 7-9% of functional human DNA and then the X-Y% of functional chimpanzee/apple/mushroom/etc. DNA.

 

[NatMorton]

The faulty assumption that a lot of people make about DNA is that all of it is functional. I.e., the entire sequence available is referenced by something or codes for something. However that's not the case. In humans the running estimate is that only something like 7-9% of our DNA is functional. The remainder is junk. It does nothing. It just sits there getting dusty.

Couple that faulty assumption with these "X percent is identical" comparisons, and what it seems like what should be the case is a predictable linear scale of difference between species. E.g., a 75% similarity match between two species means that the two organisms should look roughly 75% identical. Or a 99% similarity should result in 99% identical organisms.

But, of course, not the case because ... functionality.

The more apt comparisons would be to (for example) just compare the 7-9% of functional human DNA and then the X-Y% of functional chimpanzee/apple/mushroom/etc. DNA.

In a sense, that really doesn't matter. Even if most of our DNA is not used, we have almost the exact same unused DNA as does a chimp. That is not an accident. We both inherited most of that unused DNA from a common ancestor.

Back to humans (and the point), there just does not seem to be enough genetic drift between even the most distantly related humans to cover more than ~100k years worth of random mutations. If homo sapiens's common ancestor was ~500+k years ago, we'd see more genetic differentiation than we do.

 

[brothern]

In a sense, that really doesn't matter. Even if most of our DNA is not used, we have almost the exact same unused DNA as does a chimp. That is not an accident. We both inherited most of that unused DNA from a common ancestor.

Back to humans (and the point), there just does not seem to be enough genetic drift between even the most distantly related humans to cover more than ~100k years worth of random mutations. If homo sapiens's common ancestor was ~500+k years ago, we'd see more genetic differentiation than we do.

Yes. Correct.

 

[Channe79]

In a sense, that really doesn't matter. Even if most of our DNA is not used, we have almost the exact same unused DNA as does a chimp. That is not an accident. We both inherited most of that unused DNA from a common ancestor.

Back to humans (and the point), there just does not seem to be enough genetic drift between even the most distantly related humans to cover more than ~100k years worth of random mutations. If homo sapiens's common ancestor was ~500+k years ago, we'd see more genetic differentiation than we do.

Using rounded numbers: If 100k years went from African looking fellows to producing East Asians, how come human groups haven't changed all that must in the last 10k years ? There should be some change in how the Chinese, Indians, and Germans of today look vs what they looked like 10k years ago, shouldn't there ? At least a 10% variation in how we look. Yet, most paleoanthropologists say we haven't changed much in that time.

 

[Galactic Spin]

There's too much phenotype and biological variances and not enough time for them to have formed that way.

No.

The human species is well understood to have very little genetic variation. We even know of far more recent population bottlenecks, as the variation is SO LOW that it would be higher after 400,000 years, without population bottlenecks.

 

[NatMorton]

Using rounded numbers: If 100k years went from African looking fellows to producing East Asians, how come human groups haven't changed all that must in the last 10k years ? There should be some change in how the Chinese, Indians, and Germans of today look vs what they looked like 10k years ago, shouldn't there ? At least a 10% variation in how we look. Yet, most paleoanthropologists say we haven't changed much in that time.

How do you know there hasn't been change in the way "Chinese, Indians, and Germans look vs what they looked like 10k years ago?"

 

[gboisjo]

What does theistic babble have to do with evolution?

Nothing.

 

[Gordy327]

Nothing.

Exactly!

 

[gboisjo]

Using rounded numbers: If 100k years went from African looking fellows to producing East Asians, how come human groups haven't changed all that must in the last 10k years ? There should be some change in how the Chinese, Indians, and Germans of today look vs what they looked like 10k years ago, shouldn't there ? At least a 10% variation in how we look. Yet, most paleoanthropologists say we haven't changed much in that time.

So, whats your point ..are you saying humans didn't evolve from Great Apes.

That somehow we just appeared the way we are ..I mean how ****ing ridiculous is that.

Doesn't belong in a science thread, religion and beliefs is more appropriate.

 

[Channe79]

So, whats your point ..are you saying humans didn't evolve from Great Apes.

That somehow we just appeared the way we are ..I mean how ****ing ridiculous is that.

Doesn't belong in a science thread, religion and beliefs is more appropriate.

I do not believe all the humans above are the result of a single migration of homo sapiens who left Africa 50k years ago. That's not enough time to explain the immense diversity of how we humans look, behave, and think. We are missing something. Yes we are all human beings, yes we all share 99% of the same genetic matter. I just don't think 50k years is enough to create this much diversity in phenotype.