Species or Varieties

[doubtingmerle]

I guess it depends on how one sees it, like the cladoclast Malte Ebach, John Hawkes believes “Humans are not apes. Humans are hominoids, and all hominoids are anthropoids. So are Old World monkeys like baboons and New World monkeys like marmosets. All of us anthropoids. But humans aren’t monkeys.“

Now first it is largely due to a difference in language (how one defines terms, and there is disagreement there as well), and secondly to a difference in predisposed perspective.

It seems to me that you are getting hung up on the language and missing the evidence. The evidence is that there are many, many fossils of intermediates between humans and apes. See, for instance, http://www.talkorigins.org/faqs/homs/specimen.html .

 

[pshun2404]

Darwin thought, "I look at the term species as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other…it does not essentially differ from the term variety which is given to less distinct and more fluctuating forms." So in effect when speaking of his finches he rightly uses the term “species” as he would describe it, thus the long and short beaked finches are ever (even now) still nothing more than VARIETIES of finches (actually passerines).

Templeton later defined species as “the most inclusive group of organisms having the potential for genetic and/or demographic exchangeability.”

Later we see Nelson’s view of species and taxa as supported by D. Otte and J.A. Endler, Speciation and its Consequences (Sunderland, Massachusetts, Sinauer Press, 1989)… speaking on what constitutes a species, he tells us, “problems are insoluble, for they stem from a false assumption: that there is an empirical difference between species and the taxa such that species evolve through speciation of other species.... Evolution of taxa is not a phenomenon confined to the species level, except in neo-darwinian theory, which in this respect is simply false."

Mahr said “A biological species definition, based on the criteria of crossability or reproductive isolation, has theoretically fewer flaws than any other...Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups." (Neanderthals, Denisovans, and Sapien sapiens, would all mate with one another, but never with Apes because Apes and Humans are two different species).

I have reviewed all the evidence for about 2 and 1/2 decades as it surfaced....according to the definition science uses to define a "species" Neanderthals, Denisovans, and the Sapien sapiens are one species (homo sapiens)

 

[pshun2404]

"Anthropology can now confidently report that Neandertals, Denisovans, and others labelled archaic are in fact an interbreeding part of the modern human lineage. We are the same species. There has been extensive admixture across modern humans for tens of thousands of years, and at least some admixture across several archaic groups. Neandertals, Denisovans, and other archaics may be the best example of a true human race or sub-species. They are also fully part of the human lineage, with almost all contemporary humans showing genetic admixture with archaics in our genetic signatures."

http://www.livinganthropologically.com/anthropology/denisovans-neandertals-human-races/

John Hawkes states “We know for a fact that some Neandertal genes are today very common – for example, one 100-kilobase region occurs at a frequency of 28 percent outside of Africa. Any assignment to a species is a hypothesis, provisional on finding new facts to refute it. For the moment the facts point to them being the same species as us.”

We all have some input from Neanderthal (more or less) though slight as should be expected since most of them died out in the ice age around 100,000 years ago. Most solely African people contain no Neanderthal input (which should be expected since they stayed put. Some have Denisovan (homo sapien Altai) but more so in Tibet, Southeast Asia, and Western Native Americans. Some specifically African genes unique to ancient Sapiens from there…the rest of our genes are shared between the three groups…Neands and Denis’s had most of the same genes we have today (though some are unique in each case). Of course their gene contributions in modern man are more distant (because THEY were more distant). Gene contributions from early Sapien sapiens are also distant (time does pass you know)…but nothing anatomically or genetically would transverse what we mean when we say “species”….

In the history the actual data shows different varieties of early humans (homo sapiens) socially interacting, becoming attracted, having sex, bearing offspring to the exclusion of having this social networking and sexual interaction with Apes (not that such a mating could produce offspring anyway as we KNOW it could not)…unless you are saying "humans" were attracted to and actually had sex with "non-humans" and produced offspring...????

 

[Loudmouth]

Ancient Denisovan lineage has been found in Western Europe going back 400,000 years. They are a variety of early Homo Sapien that had already begun mingling with Neanderthals (another variety of Homo Sapiens). Since they lived in close proximity, and socially and sexually mingled, calling them “a different species” would not be accurate. The toe bone found at Denisova, in Asia, show the socio-sexual blending occurred there as well. These two varieties of human being were blending there at least 130,000 years ago. By definition if they were different species they would most likely be somewhat geo-physically and definitely sexually separated (by choice if not by nature).

If they were the same species, then there would be unhindered gene flow. This wasn't the case. For example, only 5% of some H. sapiens lineages are made up of Neanderthal DNA. That speaks to very restricted gene flow, which is consistent with being in different species.

Therefore, these were not ape-men, nor even ape-ish people, they were Homo Sapiens.

Neanderthals were definitely not H. sapiens, as the DNA evidence demonstrates.

http://www.nature.com/nature/journal/v505/n7481/full/nature12886.html

Likewise the idea that they emerged from Erectus or Heidelbergensis is entirely speculative.

What we do know is that Homo species found earlier in the fossil record are more ape-like, just as we would expect to see if evolution is true. When a theory makes accurate predictions, it is considered a supported theory.

Now it is true that all varieties of Homo Sapien share DNA in common not shared with others, and it is also true that we also share DNA in common with other primates, all mammals, and yes even with fruit and other plants, however that does not necessitate lineage either.

The fact that comparisons of DNA form a well supported objective phylogeny is evidence of common ancestry and evolution.

http://www.talkorigins.org/faqs/comdesc/section1.html#nested_hierarchy

It isn't the similarities that support evolution. It is the phylogenies.

Despite hypothesis driven interpretations of the evidence, there is no evidence which actually demonstrates man came from ape-kind, only that we share similar characteristics.

Are you saying that if we were related that we wouldn't share any DNA?

What is missing in a DNA comparison that should be there if we really did share a common ancestor?

Where Paabo believes their ancient ancestor was in fact erectus, others like Dr. Sarah Tishkoff believea this to merely be one explanation of the data, but not the only one. I tend to agree with her thought that it may or may not be the case. In my opinion, hominidae, pongidae, and hylobatae should remain separate, BECAUSE they are in fact, DIFFERENT species, and thus should not all blended under some man-made blanket term to support the accepted hypothesis.

We already have the genetic evidence that we share a common ancestor with other primates.

"Given the size of vertebrate genomes (>1 × 10^9 bp) and the random nature of retroviral integration (22, 23), multiple integrations (and subsequent fixation) of ERV loci at precisely the same location are highly unlikely (24). Therefore, an ERV locus shared by two or more species is descended from a single integration event and is proof that the species share a common ancestor into whose germ line the original integration took place (14)."
http://www.pnas.org/content/96/18/10254.full

We share thousands and thousands of endogenous retroviruses with other primate species. It is no different than finding thousands of the suspect's fingerprints all over the murder victim.

The differences in the skulls and locomotive anatomies are clearly distinct. There is no interest between humans and the alleged “other” Great Apes to form relationships or have sex and likewise no such interests form between any of the others.

My sisters are physically distinct from one another, yet they share a common ancestor.

Likewise as far as I see it, the evidence really does not show that these distinct groups of humans DIVERGED from one another at some given point, but rather that these three or more distinct varieties of humans MERGED at various times and places.

Are you forgetting that they are using divergent DNA to map the mergers?

Dr. Montgomery Slatkin from the University of California, Berkeley, tells us, “We don’t know if interbreeding took place once, where a group of Neanderthals got mixed in with modern humans, and it didn’t happen again, or whether groups lived side by side, and there was interbreeding over a prolonged period…”, but the more important point is that “interbreeding” does not occur naturally between different “species”. As Webster puts it a species is simply “a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding.” The Cambridge/Oxford definition is “a set of animals or plants the members of which have similar characteristics to each other and which can breed with each other.”

Interbreeding does happen all of the time between species. The importance is the magnitude of the interbreeding.

 

[Loudmouth]

"Anthropology can now confidently report that Neandertals, Denisovans, and others labelled archaic are in fact an interbreeding part of the modern human lineage. We are the same species. There has been extensive admixture across modern humans for tens of thousands of years, and at least some admixture across several archaic groups. Neandertals, Denisovans, and other archaics may be the best example of a true human race or sub-species. They are also fully part of the human lineage, with almost all contemporary humans showing genetic admixture with archaics in our genetic signatures."

http://www.livinganthropologically.com/anthropology/denisovans-neandertals-human-races/

John Hawkes states “We know for a fact that some Neandertal genes are today very common – for example, one 100-kilobase region occurs at a frequency of 28 percent outside of Africa. Any assignment to a species is a hypothesis, provisional on finding new facts to refute it. For the moment the facts point to them being the same species as us.”

We all have some input from Neanderthal (more or less) though slight as should be expected since most of them died out in the ice age around 100,000 years ago. Most solely African people contain no Neanderthal input (which should be expected since they stayed put. Some have Denisovan (homo sapien Altai) but more so in Tibet, Southeast Asia, and Western Native Americans. Some specifically African genes unique to ancient Sapiens from there…the rest of our genes are shared between the three groups…Neands and Denis’s had most of the same genes we have today (though some are unique in each case). Of course their gene contributions in modern man are more distant (because THEY were more distant). Gene contributions from early Sapien sapiens are also distant (time does pass you know)…but nothing anatomically or genetically would transverse what we mean when we say “species”….

In the history the actual data shows different varieties of early humans (homo sapiens) socially interacting, becoming attracted, having sex, bearing offspring to the exclusion of having this social networking and sexual interaction with Apes (not that such a mating could produce offspring anyway as we KNOW it could not)…unless you are saying "humans" were attracted to and actually had sex with "non-humans" and produced offspring...????

If there were unhindered gene flow, then we wouldn't be able to tell them apart. They are considered separate species because gene flow was restricted.

 

[pshun2404]

Not so LM! You obviously do not understand the concept of restricted versus unrestricted gene flow. Of which I am surprised actually.

This just means we can exchange inheritable material...it is just the flow of alleles from one population to another, therefore we would not all have to look the same (in fact it implies we probably would not) and we could still have many factors by which we could be told apart (skin tone, quality of hair, color of eyes, certain skeletal differences, and so on...)

Like my example of if Pygmies mated with Asians (same species different varieties)...because there is unrestricted gene flow does not mean they should or would look the same, nor that there would be a full exchange across the board...those who did mate would share a 50/50 selection of alleles via the parent-shared Chromosomes which would diminish over non-mating generations. As mixed pygmies mated in their own populations the Asian influence would become less apparent (and vice versa)...

Your article from Nature (The complete genome sequence of a Neanderthal from the Altai Mountains) clearly does not prove or even demonstrate they were not Homo Sapiens...

Almost all now agree Neanderthal and Denisovans were Homo Sapiens (thus the need to rename the African based group Homo Sapien sapiens)...that was not the question...it was are they all one species and I hold that by the definition of the term used by so many (Dobhansky, Mayr, Templeton, even Darwin) they are....

But are you saying all these scientists are incorrect? And that our common definition of what constitutes a species is also incorrect?

Not to go off topic even further but regarding the alleged ancient retroviral insertions you implied, can you demonstrate any early "human" genomes where they did not exist to show they were inserted at some given point in the past?

I have never seen a time when they were not so possibly they were always there and not insertions at all

 

[Loudmouth]

Not so LM! You obviously do not understand the concept of restricted versus unrestricted gene flow. Of which I am surprised actually.

This just means we can exchange inheritable material...

No, it doesn't. Gene flow means that we DO exchange heritable material. It doesn't matter if two populations are interfertile. What matters is if they actually exchange genes between the populations when given the chance.

For anatomically modern humans and other Homo species, the exchange of DNA between populations was rare. This is defined as restricted gene flow, and is part of the process of speciation.

Like my example of if Pygmies mated with Asians (same species different varieties)...

Why are there pygmies and Asians to begin with?

Your article from Nature (The complete genome sequence of a Neanderthal from the Altai Mountains) clearly does not prove or even demonstrate they were not Homo Sapiens...

Yeah, it does. Their DNA was different from anatomically modern humans. Here is another study:

"Our analyses suggest that on average the Neanderthal genomic sequence we obtained and the reference human genome sequence share a most recent common ancestor approximately 706,000 years ago, and that the human and Neanderthal ancestral populations split approximately 370,000 years ago, before the emergence of anatomically modern humans."
http://www.ncbi.nlm.nih.gov/pubmed/17110569

Almost all now agree Neanderthal and Denisovans were Homo Sapiens (thus the need to rename the African based group Homo Sapien sapiens)...

Who is "all"? Can you cite some papers?

But are you saying all these scientists are incorrect? And that our common definition of what constitutes a species is also incorrect?

I am a scientist, and I am telling you the definitions that we use.

Not to go off topic even further but regarding the alleged ancient retroviral insertions you implied, can you demonstrate any early "human" genomes where they did not exist to show they were inserted at some given point in the past?

They should exist in early human genomes. Many of these retroviruses inserted tens of millions of years ago in a primate ancestor that predated the emergence of all apes.

The species distribution and LTR divergence of the ERV's tells us when they inserted. An ERV that is found at the same position in many primate genomes inserted very early in the primate tree. This is independently supported by the divergence of the long tandem repeats (LTR) at the beginning and end of an ERV. When a retrovirus inserts into a genome, the 2 LTRs are identical in sequence. Since there is no mechanism that would keep the LTRs the same over time within the host genome, the longer they are around the more mutations they accumulate and the further they diverge from one another. Therefore, if common ancestry and evolution are true you should see a correlation between species distribution and LTR divergence, and that is exactly what we see. The ERVs found most widely in the primate family are also the ERVs with the greatest LTR divergence.

I have never seen a time when they were not so possibly they were always there and not insertions at all

We can watch retroviruses producing ERVs in the lab. ERVs contain all of the parts of a retrovirus, from the LTRs to the gag, pol, and env genes. Why shouldn't we conclude that the ERVs we see in the genomes of humans and other primates was from a retrovirus? The kind of denial you are pushing is like trying to ignore fingerprint and DNA evidence at a crime scene.

 

[Loudmouth]

Although I don't like using secondary sources, this is a well sourced quote:

"Some of the genes, meanwhile, appear to have led to fertility problems. For instance, Sankararaman found that the X chromosome is almost devoid of Neanderthal DNA. This suggests that most Neanderthal DNA that wound up on the X chromosome made the bearer less fertile – a common occurrence when related but distinct species interbreed – and so it quickly disappeared from the human gene pool. “Neanderthal alleles were swept away,” says Sankararaman.

“This underlines that modern humans and Neanderthals are indeed different species,” says Fred Spoor of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who was not involved in any of the studies.

The genetic evidence further backs this up. Neanderthal DNA is irregularly spaced through the modern human genome rather than being fully mixed. That implies that interbreeding occurred very rarely. Sankararaman estimates it may have happened just four times."
https://www.newscientist.com/articl...red-light-skins-and-infertility/#.Uu1F0LT4LvY

It would seem that the scientists think modern humans and Neanderthals were separate species.

 

[pshun2404]

I guess these few deny the opinion of the many...what can we do? One group will in the end turn out to be correct...we will see! Some say they are all "sub-species" a smaller group say "different species"....hmmm?

Speaking of another contender, Herto Man, F. Clark Howell, UC Berkeley professor emeritus of integrative biology and co-director with Tim White of UC Berkeley's Laboratory for Human Evolutionary Studies believes “these anatomically modern humans pre-date most neanderthals, and therefore could not have descended from them, as some scientists have proposed” (UC Berkley News, “160,000-year-old fossilized skulls uncovered in Ethiopia are oldest anatomically modern humans”, R. Sanders, June 2003).


Many are rallying this interpretation (not all) but if one looks at the actual evidence it simply cannot be true. Everyone is saying these are the earliest “modern humans” by this I assume they mean “Homo Sapiens” not Homo Sapien sapiens! Though they pre-date the main bodies of Neanderthals we know of so far (rhetorically posed as “most”) we have evidence of Neanderthal using sophisticated techniques for making pitch that pre-date these other alleged Homo Sapiens by at least 100,000 years.


IMO they have made this intentional misrepresentation (their interpretation) so they can call this an intermediary form between other hominids and homo sapien. But it fails if one observes the finds that we have objectively because sub=species of homo sapien obviously pre-existed these alleged “modern humans”!


Tim White (as predictively expected) says "We've lacked intermediate fossils between pre-humans and modern humans, between 100,000 and 300,000 years ago, and that's where the Herto fossils fit”

(pre-human actually only referring to any fossil of any creature that existed before humans but planting the innuendo into the minds of the inundated masses that this forms a link to apes like Habalis and Australopithicus)


One that really stirs the pot (though from a later period) is Australia’s Mungo Man…he is very much a Homo Sapien sub-species with a quite modern anatomy and cranium but has zero linkage genetically to “Out of Africa” man. His mitochondrial DNA is absolutely distinct and he bears no connection to Euro-Asian Neanderthals either. His line died out about 60,000 years ago but they demonstrate (by ritualized burial) that they were socially conscious individuals. The point is, here is yet another “man” not of African origin yet the rhetoric continues to be imposed on our students. This is not only bad reporting in science but dishonest in education showing us there is a degree of intentional indoctrination being mixed in.

 

[Loudmouth]

I guess these few deny the opinion of the many...what can we do?

More than 99.9% of biologists accept the theory of evolution. Do you accept the theory of evolution?

Also, you have not shown that most scientists publishing in the area of human origins have the opinion that Neanderthals and anatomically modern humans were the same species.

Some say they are all "sub-species" a smaller group say "different species"....hmmm?

How did you determine which group was the smaller of the two?

Speaking of another contender, Herto Man, F. Clark Howell, UC Berkeley professor emeritus of integrative biology and co-director with Tim White of UC Berkeley's Laboratory for Human Evolutionary Studies believes “these anatomically modern humans pre-date most neanderthals, and therefore could not have descended from them, as some scientists have proposed” (UC Berkley News, “160,000-year-old fossilized skulls uncovered in Ethiopia are oldest anatomically modern humans”, R. Sanders, June 2003).

Yet another expert who has Neanderthals and modern humans as separate species. If they were the same species, then he would describe them both as modern humans.

Many are rallying this interpretation (not all) but if one looks at the actual evidence it simply cannot be true. Everyone is saying these are the earliest “modern humans” by this I assume they mean “Homo Sapiens” not Homo Sapien sapiens! Though they pre-date the main bodies of Neanderthals we know of so far (rhetorically posed as “most”) we have evidence of Neanderthal using sophisticated techniques for making pitch that pre-date these other alleged Homo Sapiens by at least 100,000 years.

What does that have to do with anything? We can be separate species and both use technology.

IMO they have made this intentional misrepresentation (their interpretation) so they can call this an intermediary form between other hominids and homo sapien.

A species can be intermediate even if they aren't direct ancestors. Intermediate and ancestral ARE TWO DIFFERENT THINGS.

But it fails if one observes the finds that we have objectively because sub=species of homo sapien obviously pre-existed these alleged “modern humans”!

How do you determine if a fossil from hundreds of thousands of years ago is the same species as a living organism? What tests are you using? What criteria are you using?

One that really stirs the pot (though from a later period) is Australia’s Mungo Man…he is very much a Homo Sapien sub-species with a quite modern anatomy and cranium but has zero linkage genetically to “Out of Africa” man.

What makes him a sub-species instead of a separate species?

 

[Gene2memE]

I've been doing the reading here, and the issue is that there is still not a clear consensus on the place of H. neanderthals in H. sapiens origins, or even the taxonomic status of H. neanderthals.

There are a couple of camps, that are arguing their cases.

One of the camps argues for a 'single-origin' model (aka the Out of Africa model), and place H. neanderthals as a distinct species with minimal contribution to the evolution of modern humans. This is the predominant, though far from exclusive view.

Another, the 'multi regional' camp, consider H. neanderthals as a H. sapiens subspecies, with a more significant contribution to the evolution of early modern Europeans. This camp saw its case wax and wane over the past decade, thanks to a number of genetic studies on archaic homonids.

There are also modified versions of both hypothesis being argued and tested.

There's a wrinkle though - the genetic evidence evidence from H. Neanderthals and Denisova doesn't support either hypothesis conclusively.

So the answer is - we don't know enough to conclude either way yet, but the picture is probably much more complicated than we though even 10 years ago.

 

[Derek Meyer]

I've been doing the reading here, and the issue is that there is still not a clear consensus on the place of H. neanderthals in H. sapiens origins, or even the taxonomic status of H. neanderthals.

Hope you do know that the debate on where to place Neanderthals is excellent evidence for the ToE? Those other pesky great ape fossils in the middle; not "fully human" , but could interbreed with some humans, but also not like other great apes such as gorillas or chimps... Somewhere in the middle.

Most modern people of European descent have around 5% the X chromosome from Neanderthals, while the Y-Chromosomes from Neanderthals into humans have been weeded out...Other people from Asia have chromosomes from Denisovians. What better evidence for the ToE?

 

[Derek Meyer]

I guess these few deny the opinion of the many...what can we do? One group will in the end turn out to be correct...we will see!

Actually, in science, there usually is a scientific consensus and the opposite groups come together an realise that it's not either/or, but combinations.

The consensus at the moment is that all forms of humans originated in East and Central Africa, some early forms of humans moved out of Africa, lived in the Middle East and Europe and parts of Asia, then later forms of humans moved out of Africa and interbred with some forms of humans in the Middle East, Europe and Asia.

All forms of humans still originated in Africa. That's the scientific consensus. It's the out of Africa model and in the multiregional model.

 

[Loudmouth]

One of the camps argues for a 'single-origin' model (aka the Out of Africa model), and place H. neanderthals as a distinct species with minimal contribution to the evolution of modern humans. This is the predominant, though far from exclusive view.

That's my conclusion as well. The predominant view is that we were separate species. We have DNA from many human species from that time period, and they are distinct. If they were all one species we wouldn't expect to see this much of a difference between groups, at least from what I have read. What we do see is very small contributions from Neanderthals in modern human genomes, which is consistent with rare and limited interbreeding.

Another, the 'multi regional' camp, consider H. neanderthals as a H. sapiens subspecies, with a more significant contribution to the evolution of early modern Europeans. This camp saw its case wax and wane over the past decade, thanks to a number of genetic studies on archaic homonids.

The idea is that modern human DNA spread in a manner analogous to the old telephone game. This is where you whisper something to one person, and then they try to whisper that same thing to the next person in line. The idea is that Africans interbred with surrounding human populations. Those surrounding human populations did the same. On and on it went until African human DNA was spread to all populations.

The problem I see with the MR hypothesis is the lack of Neanderthal mitochondrial DNA. If interbreeding was common and unrestricted, then why don't we see any surviving mitochondrial lineages from those Neanderthals? The mitochondrial lineages we see today match the mitochondrial lineages we have pulled from ancient anatomically modern humans, and not Neanderthals. The same applies for the Y-chromosome.

Could we find a very rare surviving lineage of Neanderthal mtDNA or Y-chromosome? Yes, it is possible. However, given the apparent rarity of both, it supports rare interbreeding instead of free gene flow.

 

[doubtingmerle]

What we do see is very small contributions from Neanderthals in modern human genomes, which is consistent with rare and limited interbreeding.

I am curious how we would get a "very small contribution" from Neanderthals. Humans have 46 chromosomes, so if Neanderthals make very little contribution, I would think that means some rare humans have a whole chromosome (with mutations) or perhaps 2 chromosomes from Neanderthals. But that doesn't seem to be what I am hearing from this thread and some of the links I have clicked. They seem to be saying that most people have a small fraction of a chromosome from Neanderthals. Are we saying that Neanderthals somehow contributed fragments of a chromosome to some individuals that remained in the human genome? How would that happen?

 

[Loudmouth]

I am curious how we would get a "very small contribution" from Neanderthals. Humans have 46 chromosomes, so if Neanderthals make very little contribution, I would think that means some rare humans have a whole chromosome (with mutations) or perhaps 2 chromosomes from Neanderthals. But that doesn't seem to be what I am hearing from this thread and some of the links I have clicked. They seem to be saying that most people have a small fraction of a chromosome from Neanderthals. Are we saying that Neanderthals somehow contributed fragments of a chromosome to some individuals that remained in the human genome? How would that happen?

The answer lies in the process of meiosis, the type of cell division that gives rise to sperm and eggs. Here is a decent pic:

During meiosis, there is a stage (Metaphase II) where homologous chromosomes trade DNA. Think of it as shuffling the deck. This caused Neanderthal genes to mix with human genes on the same chromosome. An individual who had a modern human and neanderthal as parents could give its offspring a chromosome that is 50% modern human and 50% Neanderthal. As you repeat this process through the generations, this can dilute the initial contribution of Neanderthal genes if it was a rare or isolated event. If a Neanderthal gene, or DNA close to that Neanderthal gene, are selected for through natural selection then it has a much better chance of becoming a permanent part of the modern human genome.

 

[Astrophile]

the second is that because something exists before something else that that necessitates one came from the other,

But if you think about it, you will realise that everything that is alive now is descended from a selection of the things that were alive, say, 5.3 million years ago, near to the Miocene-Pliocene boundary. Since there is no fossil evidence of anything human in rocks from the Miocene-Pliocene boundary, we have to infer that we are descended from one of the species of apes that lived at that time.

 

[pshun2404]

A chamber at Sima de los Huesos in Spain has unveiled the remains of 28 individuals dating back to 400,000 years. What can we say about this skeleton? When we observe the skull and these lower legs should we call them ape-like (they ARE Neanderthal and Denisovan genetically)? Are they not anatomically equal to modern Homo Sapiens?

 

[pshun2404]

But if you think about it, you will realise that everything that is alive now is descended from a selection of the things that were alive, say, 5.3 million years ago, near to the Miocene-Pliocene boundary. Since there is no fossil evidence of anything human in rocks from the Miocene-Pliocene boundary, we have to infer that we are descended from one of the species of apes that lived at that time.

No! It CAN BE inferred, but we do not have to assume such a relationship. Since most humans were buried only a few feet down and the rest were surface dwellers, there may be reasons they do not demonstrate many fossils (though we are seeing evidence for them further back in time than previously supposed/inferred).

 

[Loudmouth]

A chamber at Sima de los Huesos in Spain has unveiled the remains of 28 individuals dating back to 400,000 years. What can we say about this skeleton? When we observe the skull and these lower legs should we call them ape-like (they ARE Neanderthal and Denisovan genetically)? Are they not anatomically equal to modern Homo Sapiens?

Why don't you show us a picture of the fossil and we can discuss. For comparison, here is a modern human skull.

The first feature we can look at is the eyebrow ridges, which are much reduced compared to earlier Homo species. Second, the forehead vaults quite high over the eyebrow ridge, unlike earlier Homo species which have a forehead that slopes back from the brow ridge. Third, the bottom front of the jaw has a forward jutting process. This is also a feature seen with modern humans but not earlier Homo species. For example, this is H. erectus:

Here we have a pronounced brow ridge, backwards sloping forehead, smaller cranium, and a lack of a forward jutting process on the front of the lower jaw.