Re: Were Neanderthals another species of Homo Sapiens?

On 12/8/24 1:01 PM, JTEM wrote:

 No.

Well, thanks for making an argument using actual support from published literature, and thanks for having fewer insults than usual.

  RonO wrote:
 

Two anthropologists are making the case that Neanderthals were different enough to be considered to be a different species from modern humans.

 There's a better case that everyone/everything following habilis is
the same species.
 https://pubmed.ncbi.nlm.nih.gov/12733395/
 Predicted response:  "It's too old!"
 What the response should be:  "Here's a cite that refutes it."
 THAT doesn't happen though...
 The point is that all these claims are based on assumptions, and
the assumptions in the "Different Species" claim are not only
questionable but unnecessary. Put short:  They don't tell us
anything of value.
 

We could obviously interbreed, but there were physical and genetic differences.

 Is this NOT to be expected?
 Seems to me to appear exactly as it should:  Divergences as temporal
distance expands, convergence as it closes...
 The further back we go, the bigger the differences. The closer in
time to us, the fewer the distances.

True, but the neandertal genomes are from much more recent fossils than the estimated time of divergence, so that's not a significant factor. One can also, of course, correct the divergence estimates for fossils of substantially different ages.

How could it be any other way?
 

We are around as different from Neanderthal in our DNA sequence as Bos taurus (western domestic cattle) and Bos indicus (Asian domestic castle).  Taurus and indicus can freely interbreed, but the Auroch populations that they were derived from had been genetically separated for over half a million years.

 Again:
 https://pubmed.ncbi.nlm.nih.gov/12733395/

According to the above, you're shy about 75%.

I didn't see any relevant claim there, but in any case that publication uses an odd species concept in which genetic distance is the only relevant factor. But if speciation —- evolution of an isolating mechanism —— is rapid, then you can have completely isolated species that are genetically identical at most loci other than the ones creating isolation. There are a number of bird species, for example, that do not interbreed but that can't be distinguished by mitochondrial haplotype. If we go with the biological species concept, their argument doesn't work; if we go with their implied species concept, species are quite a different thing from what we commonly suppose, and isolating mechanisms are irrelevant.
There are a number of other problems with that abstract, but that's the one that annoys me most.

This is about the same amount of time that Neanderthals and Modern humans have been estimated to have been separated.

 So an assumption based on an assumption.

No, based on genetic distance. Unless you have reason to believe that the rate of evolution in one or both lineages is much different from current estimates, you should accept those estimates.

The physical differences are mainly due to Neanderthal having to survive multiple 100,000 year long glacial periods.

 An assumption.
 Case in point:  The Habsburgs
 Inbreeding is a VERY powerful influence.
 Also Google:  Founder Effect
 Neanderthal populations were small, they would have suffered a
number of "Bottleneck" events... why pretend that they were
shaped exclusively by climate?

Possible. The implicit assumption is that morphology is shaped by selection rather than drift. Might not be true.

Neanderthal retain many features associated with Homo erectus

 Is there a reason why they should not have?
 My stock example is sauropod dinosaurs. The really BIG dinosaurs!
Their anatomy looks so much like their bipedal cousins that some
have suggested that they often reared up on their hind legs. A
far simpler explanation though is that BECAUSE THEY EVOLVED FROM
BIPEDAL ANCESTORS, they retained much of their anatomy. How? Why?
Because why wouldn't they?  We're not discussing Intelligent
Design, we're speaking of evolution. Without selective pressures
on losing a trait, the trait should remain.
 The big issue here is likely Toba and maybe one or more other
bottlenecks. They favored the African population, and that African
population was sexually selected.
 Do the Google on r-K selection...
 BECAUSE there wasn't "a" population in Africa. There were many.
And "The One" to win the race, to bounce back first, repopulate
and start filling the vacuums was the sexually selected group.
 Predicted response:  "You're claiming Africans are dumb! That their
evolution was dictated by boners!
 No, WokeTarded twits. I'm saying EURASIANS are! That, what we
pretend are "Modern Humans" were a sexually selected group that
recovered FIRST, spread in the vacuum left by other groups and
outbred the older populations... which would be us.

The claim you're making here is unclear.