Did humans descend from other primates?

[McCulloch]

Man did not descend from the primates.

Did humans descend from other primates?
Are humans primates or should there be special biological taxonomy for humanity?
Please cite evidence.

[Goat]

Predictions=brain size smaller, height shorter, weight less, less well developed walking(as opposed to grasping)feet, shorter lifespans, fewer and cruder tools as you go backward in time.

The average height and size of Homo heidelbergensis is larger than humans. Cranal capacity is also quite large.

"Homo heidelbergensis had a larger brain when compared to other hominid species, and a body type which appears to be very similar to that of modern humans, although Homo heidelbergensis was somewhat taller."
http://www.wisegeek.com/what-was-homo-h ... gensis.htm

"The species was tall, 1.8 m (6 ft) on average, and more muscular than modern humans."
http://en.wikipedia.org/wiki/Homo_heidelbergensis

"H. heidelbergensis had a larger brain-case, up to 1400 cc, more than the 1350 cc average of modern humans."
http://news.softpedia.com/news/Top-10-E ... 2131.shtml

"He resembled a modern human but was more robust and slightly taller, averaging about 6 feet in height for adult males."
http://wiki.cotch.net/index.php/Homo#Ho ... lbergensis

How to falsify these predictions=show how primitive hominids do not have these features, but are fully formed modern humans(as created 6000 years ago)in every case, even as we look further back in time.

As mentioned in the links above, Homo heidelbergensis is similar to humans, but just larger.

Your point?? Similar is not the same. The TOE says that things happen in small steps. Having it 'similar' but either bigger or smaller is exactly what would be expected. 100% expected.

The TOE says that changes happen small steps at a time, and over time, the accumulated small changes can account for new species. What you are describing is 100% in line with what the TOE predicts .. not only for humans, but for all species... the older species it develops from is almost identical.. but the previous species to that is a bit more different.

Go back a few million years, and the species that are extant are even more different. But, the TOE specifically says that changes are small steps at a time.


Now, I see you taking much time to try to attack the evidence presented for Evolution, and to hand wave the predictions and evidence of evolution away. What I have not seen from you is anything more than 'An intelligent designer can explain that too', and attacking the evidence for evolution.

What is the evidence for an intelligent designer? How can you distinguish evidence for evolution with your claims for 'an intelligent designer can explain that too'?

What is the criteria for evidence for an intelligent designer. Some of the criteria for the evidence for evolution is 'one small step at a time', and 'consistency of morphology verses the age of a fossil'.

[Grumpy]

otseng

As mentioned in the links above, Homo heidelbergensis is similar to humans, but just larger.

Very similar, but not quite modern man. But he is probably our nearest ancestor(as well as Neanderthal's ancestor)and is in the genus Homo(Man). He is an ancient human. You have not shown that Homo heidelbergensis did not descend from lesser creatures.

God created the first man and woman (tens of thousands of years ago).

The last Homo heidelbergensis died at least 200,000 years ago. He was either man's ancestor(meaning the second of the above quotes can not be true)or he didn't exist. God-did-it explains absolutely nothing and is a religious belief, not science.

Oh, the human bottleneck happened 75,000 years ago when Toba caused mass extinctions worldwide.

"The volcano ejected an estimated 800 cubic kilometers of ash into the atmosphere, leaving a crater (now the world's largest volcanic lake) that is 100 kilometers long and 35 kilometers wide. Ash from the event has been found in India, the Indian Ocean, the Bay of Bengal and the South China Sea.

The bright ash reflected sunlight off the landscape, and volcanic sulfur aerosols impeded solar radiation for six years, initiating an "Instant Ice Age" that -- according to evidence in ice cores taken in Greenland -- lasted about 1,800 years.

In 1998, Ambrose proposed in the Journal of Human Evolution that the effects of the Toba eruption and the Ice Age that followed could explain the apparent bottleneck in human populations that geneticists believe occurred between 50,000 and 100,000 years ago. The lack of genetic diversity among humans alive today suggests that during this time period humans came very close to becoming extinct."

http://www.sciencedaily.com/releases/20 ... 142739.htm

Maybe you are talking about the end of the last Ice Age between 10,000 and 15,000 years ago, that's when Homo Sapiens Sapiens appears.

You know, when the history of life on Earth is known as well as we now know it this...

Human Creation Model:
- God created the first man and woman (tens of thousands of years ago).
- God created the first humans distinct from the animals.
- All humans arose from the first couple.
- A global flood occurred. Noah and his sons and all their wives were the only humans (total of 8) to survive. They repopulated the Earth near the Middle East.

Predictions:
- All humanity traces lineage to one man and one woman.
- There is no gradual transition from animals (specifically primates) to humans.
- Humanity traces origins to around the Middle East area.
- Origin of man traces to tens of thousands of years ago.
- Greater genetic diversity of females than males during the Flood. Males were direct descendants of Noah. Their wives were not direct descendants of Noah's wife.
- Human culture should appear quickly in history.

...is really rather ridiculous.

Grumpy

[SailingCyclops]

Human Creation Model:
- God created the first man and woman (tens of thousands of years ago).
- God created the first humans distinct from the animals.

Since this is biblically based, can I safely assume that this model mandates that all life including vegetation was created as is, at about the same time? Within the same 6 days?

Bob

[SailingCyclops]

... What it should be based on is the evidence presented. And if human evolution is indeed a fact, it should be quite simply to prove, without simply relying on the vast majority of scientists in the field agreeing with it.

Given the very technical biological discussions upthread, I don't think this is a fair statement. It is obviously not "simple", otherwise several scientific disciplines would not be involved in the discovery process.

To deal with my high blood pressure, I get advice from my doctor. He prescribes chemicals, I research those chemicals to the best of my ability to verify they are correct for me. However, I do not have the background in chemistry to understand the pill's activity on the molecular level. I leave that up to the chemists.

I no more need to be a biologist, an archaeologist, a geneticist, or a paleontologist to know about evolution, than I need to be a surgeon to have my appendix removed.

Bob

[Abraxas]

Human Creation Model:
- God created the first man and woman (tens of thousands of years ago).
- God created the first humans distinct from the animals.
- All humans arose from the first couple.
- A global flood occurred. Noah and his sons and all their wives were the only humans (total of 8) to survive. They repopulated the Earth near the Middle East.

Fair enough. Let's see how it pans out.

Predictions:
- All humanity traces lineage to one man and one woman.

I'd like to modify that. I hope you have no objection to changing it to "- All humanity traces lineage to the pairing one man and one woman."

This is not what we find. Instead, we find that the mitochondrial Eve lived 200,000 years ago but the comparative Adam lived a mere 60,000-90,000 years ago.

http://en.wikipedia.org/wiki/Y-chromosomal_Adam
http://en.wikipedia.org/wiki/Mitochondrial_Eve

Firstly, as the two did not exist during the same time frame, they certainly could not have produced offspring together. Secondly, as there is not a comparable Adam or Eve in each of their time frames, we are looking at multiple sexual partners, at least for Adam as otherwise an Eve would exist in his timeframe. This prediction is wrong.

- There is no gradual transition from animals (specifically primates) to humans.

http://en.wikipedia.org/wiki/Human_evolution

That prediction fails pretty dramatically. We have countless fossils from the past few million years showing gradual changes to what is modern man.

- Humanity traces origins to around the Middle East area.

Give you this one.

- Origin of man traces to tens of thousands of years ago.

False, per the above, we can trace Man back millions of years with declining degrees of resemblance.

- Greater genetic diversity of females than males during the Flood. Males were direct descendants of Noah. Their wives were not direct descendants of Noah's wife.

Presupposes a flood to begin with, but more than that it is not testable. The genetic variation would become more uniform across both sexes within just a few generations. The reason we can track it in men is through the Y chromosome, but as the X chromosome exists for both males and females, it is impossible to follow.

- Human culture should appear quickly in history.

Falsified by cave drawing and tools dating back tens to hundreds of thousands of years.

http://en.wikipedia.org/wiki/History_of ... technology
http://en.wikipedia.org/wiki/Cave_drawing

Falsified by:
- A gradual transition is found from animals to humans in the fossil record.

Shown above.

- Genetic changes from one species to another and leading to humans are identified.

http://en.wikipedia.org/wiki/Human_evol ... y_genetics

Thus, as I think most expected, the Human Creation Model fails in all but one prediction, and is falsified by evidence.

[SailingCyclops]

"He resembled a modern human but was more robust and slightly taller, averaging about 6 feet in height for adult males."

That's not the case for Homo floresiensis which is an entirely different human species. They lived between 95,000 and 13,000 years ago. Making their existence contemporaneous with modern humans. They Used fire, made stone tools (technology), hunted large prey in groups (so had at least a rudimentary language) but had a brain 1/3 the size and of a completely different structure from modern humans. The Nova video is here: Alien From Earth See also : How a hobbit is rewriting the history of the human race.

Humans are defined by the following attributes: bipedalism -- highly developed brain, capable of abstract reasoning, language, introspection, and problem solving -- use of tools -- build fires, cook their food. All attributes of this species. So, were two different species of humans created at the same time?

Bob

[Dr.Physics]

Did humans descend from other primates?
Are humans primates?

yes

[otseng]

Which leads me to wonder, is there data showing roughly what percentage of mutations result in detrimental, neutral, and beneficial results?

Sorry, when you say mutations do you mean ERV insertions or any mutations? In the former case, I don't know of any papers trying to quantify the ratio of outcomes. In the latter case, there are many papers about the outcomes of single-nucleotide mutations in genes (whether silent (neutral) or not, and whether non-silent mutants are detrimental (many) or beneficial (a few)).

First let me say that I appreciate your thoughtful responses and patience in answering my questions.

When I read posts, I try to understand to the best of my ability what the poster is saying. And since this is an area I've never studied before, it's taking me awhile to research and understand the concepts.

OK, back to answering your question.

Either case (ERV mutations or all mutations) would be fine. Just curious about what is roughly the percentage values.

And another question, how do geneticists decide if something is an ERV?

During the part of their life cycles when retroviruses insert themselves into host genomes, they look like this.


Figure 1: Schematic of retroviral genome arrangement


Figure 3: Schematic of retrotransposon structure
Look familiar? The POL gene (under the control of the LTR) allows the retrotransposon to copy itself. Without working copies of the capsid proteins (GAG) or envelope proteins (ENV), it cannot make new virus particles.

Since ERV and retrotransposon are of similar structure (seemingly identical to me), does that mean that all retrotransposons are an ERV (or can trace its source to an ERV)? If not, how can one distinguish between the two?

To find ERVs, researchers look at genomic sequence data for retroviral genes. Possible hits may look like these (many others are possible, but you get the idea):


Figure 2: Some possible ERV structures

The first case is the equivalent of a "completely intact fossil." All of the genes found in live retroviruses are present (though inactive) and in an order corresponding to a living class of retrovirus.

The second case gives another example of a "completely intact fossil," albeit a partially active one. The LTR still promotes expression of the GAG gene (it could easily be another viral gene), though without the full suite of retroviral genes this ERV is not pathogenic (in most cases). Sometimes expression of partially active ERVs can lead to autoimmune response[1]. Conversely, these genes (though initially neutral) may be co-opted by natural selection to serve host-beneficial functions.[2]

The remaining classes are "partial fossils." These partially deleted fragments may or may not have regulatory activity or gene expression, but they match the general arrangements of other retroviruses.

I understand the first and second cases, but for the others, is it simply because of the existence of a LTR that shows it originally was an ERV and has experienced deletion of material?

Granted, but there's nothing to stop a neutral ERV from gaining a beneficial function. Regardless of whether such a beneficial mutation is passed to subsequent species, creationists shouldn't take issue with the initial neutral-to-beneficial mutation - it would be an example of "microevolution" within a species.

I do not totally discount the possibility of a mutation to result in a beneficial function. But my guess is that the percentage of such mutations would be significantly less than detrimental mutatations.

Far less than 1% of known ERVs show this function - didn't the creationist position hinge on finding many, many functional ERVs?

Since transposons were only discovered relatively recently, I think it would be fair to say that there is still much research that can be done in this area. If further research confirms that ERVs have no function, I acknowledge that it would be more plausible to explain it by evolutionary common descent.

Far less than 1% of known ERVs show this function - didn't the creationist position hinge on finding many, many functional ERVs?

It would be a prediction, yes, that a significant portion of ERVs should have function. And if future research confirms that ERVs are functionless, it would falsify this prediction.

Why do we observe inactive viral genes that are not required for the function of syncytin? Why does a designer include these functionless components when the ENV/syncytin is the only part that's required?

If we do not know the function of something now, it does not necessarily mean that it is actually functionless.

Take for example introns:

Introns may also contain "old code", or sections of a gene that were once translated into a protein, but have since become inactive. It was generally assumed that the sequence of any given intron is junk DNA with no biological function. More recently, however, this is being disputed.

http://en.wikipedia.org/wiki/Intron

And even all ERVs were also assumed to be functionless, but research is starting to reverse this assumption.

Since LTRs are all that is required for gene regulation, why do we often see inactivated viral genes along side them (Figure 5)? These genes may be mutationally reactivated to cause diseases like cancer or MS.

When you say "mutationally reactivated", it would imply the purpose of the original sequence was to cause cancer or MS.

The most parsimonious explanation for these viral relics is retroviral insertion and subsequent natural selection. And if retroviral insertion is truly the cause of ERVs (functional or not), then the incredible odds against random insertion of the same viral strain at the same genomic locus across species provides incredibly strong evidence for shared ancestry. (The inescapable fact creationists were trying to avoid by invoking design of ERVs.)

Again, I would agree with this if ERVs are actually functionless. But, would you also agree that if a signficant portion of ERVs are found to have function, then the better explanation is purposeful design?

[otseng]

what about the 1%-4% neanderthal DNA that all non africans possess? how do you explain this, if not through lineage?

Are you claiming that Neanderthals are ancestors of humans?

[SailingCyclops]

Are you claiming that Neanderthals are ancestors of humans?

It seems we share a close common ancestor, and there was Neanderthal interbreeding with humans.

Bob