Posted on 12/17/2024 5:58:14 AM PST by Red Badger
A replica of an approximately 50,000-year-old Neanderthal cranium from La Ferrassie, France, compared to a recent Homo Sapiens cranium. Credit: Trustees of the Natural History Museum A study suggests that by the time H. sapiens expanded, the differentiation between the two species had progressed to the extent that they were distinct and recognizable as separate species.
A recent study conducted by researchers from London’s Natural History Museum and the Institute of Philosophy at KU Leuven has strengthened the argument that Neanderthals and modern humans (Homo sapiens) should be classified as distinct species to more accurately trace our evolutionary history.
Different researchers have different definitions as to what classifies as a species. It is undisputed that H. sapiens and Neanderthals originate from the same parental species, however studies into Neanderthal genetics and evolution have reignited the debate over whether they should be classed as separate from H. sapiens or rather a subspecies (H. sapiens neanderthalensis).
Evidence Supporting Species Distinction
Advocating the former, Chris Stringer (Natural History Museum, London) and Andra Meneganzin (Institute of Philosophy, KU Leuven, Belgium) state that despite the inherent limitations of the fossil record, there is enough morphological, ecological, genetic, and temporal evidence to justify this categorization, and claim that this evidence reflects the complexity of the speciation process, in which populations from one parent species progressively diverge to become different descendant species. Taxonomic disagreement, they claim, is best explained by how the speciation process is modeled in the record, rather than conflicts between evidence types.
Dr. Andra Meneganzin, Post-doctoral Fellow at the KU Leuven Institute of Philosophy and lead author of the study, says: “In the science of human origins, implicit and unrealistic theoretical assumptions can be just as limiting as the scarcity of data. Taxonomic disagreement over the classification of our species and Neanderthals offer a prime example of oversimplified expectations regarding the nature of speciation. Both in present and past taxa, speciation unfolds across space and time, through multiple stages involving the incremental acquisition of distinct characters. By reading the fossil records through the temporal and geographic dimensions that shaped past human diversity, available data can become increasingly informative rather than more limiting, and help move debates beyond unproductive deadlocks.
Professor Chris Stringer, Research Leader at the Natural History Museum and joint author of the paper, says: “In the context of Neanderthals and Homo sapiens, we need to regard speciation as a gradual process that occurred over more than 400,000 years. It is correct that the two interbred where they were not geographically separate, but over time differentiation continued to a point where the two were distinctly different species. When the Neanderthals died out around 40,000 years ago, the two species were in the final stage of the speciation process and were developing reproductive isolation from each other.”
Challenges in Mapping Speciation
Mapping speciation over a 400,000-year period from palaeontological and archaeological evidence has proven challenging for scientists, as in the later stages of speciation H. sapiens and Neanderthals continued to interbreed and exchange genes and behaviours. However, to reliably trace modern human evolution, categorizations need to be made about anatomical and geographical developments. The study claims that if interbreeding was the final word in determining species status, then hundreds of distinct species of mammals and birds today would have their separate species status revoked and that without recognizing patterns in evolution and subsequent categorization, the question of when a species first appeared becomes more intractable.
Fossil records show that H. sapiens developed in Africa, whilst Neanderthals evolved in Eurasia for at least 400,000 years, with interbreeding occurring as H. sapiens expanded out of the former region. However, the study argues that by the time of H. sapiens expansion and subsequent interbreeding, differentiation between the two species had occurred to the point where they were distinguishable species. One striking example of differentiation is that their ecological profiles were distinguishable and associated with “minimally different” habitats.
Neanderthals were better equipped to cope with colder climates – an adaptation which even today we have not yet fully developed without the use of technology. They had to be more physically active and for longer periods, to gather the resources they needed for survival, which helps to explain morphological differences including ribcage and pelvis shapes, inferring bigger internal organs such as the lungs, heart, and liver – amongst a wide range of anatomical distinctions. This may have been a factor in their extinction, as the more gracile skeleton of H. sapiens suggests a more economical physiology, less demanding of energy and resources, and aided by complex technology. This could have made the difference between survival and extinction when there was rapid climate change, or a strong competition for resources where the two coexisted.
An ever-evolving field of research, this bold new paper hopes to provide an explicit theoretical framework for future study, calling for a more nuanced chronological and evolutionary contextualisation of the available fossil record.
Reference:
“Homo sapiens, Neanderthals and Speciation Complexity in Palaeoanthropology”
by Andra Meneganzin and Chris Stringer, 14 November 2024, Evolutionary Journal of the Linnean Society.
DOI: 10.1093/evolinnean/kzae033
“Interbreeding with fertile offspring says there was only one species involved unless”
Yes, exactly. If they want to say that Neanderthals were a separate species, then they need to change the definition of “species” to remove the fertility/sterile elements. Maybe it’d be more accurate to say that Neanderthals were a “race.”
> The study claims that if interbreeding was the final word in determining species status, then hundreds of distinct species of mammals and birds today would have their separate species status revoked
And there goes the EPA’s power to declare species “endangered” or “protected” and f*** with people’s lives.
Last Sunday my folks were playing a tune that went, “She wouldn’t let you inside, then she turned and said, but honey, he’s not our kind!”
It could mean Africans didn’t like ugly folk, or Neandertals were racists.
I evolved from a long line of hetero erectus.
So, you’re not a ‘homo’?........................
always loved them women.
Any Neanderthal DNA brought back to life still has a “First Nations” claim over all of Europe.
Reparations time!
Lol.
The “Endangered Species Act” decided no species, no matter how insignificant could be allowed to go extinct, no matter the cost or impact.
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In any given subset of its possible range as determined by University Profs and grad students.
In flowers they would be varieties.
The whole “Out of Africa” theory is currently out of favor.
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My money is on Antarctica as the prime radiant before it froze over 14 million years ago.
“Some people will buy and plant hybrid corn getting a great crop, then plant the seeds and expect the same The stalk may come up but the ear of corn is a failure.”
Correct, must use heirloom seeds to reproduce.
If they could breed, they were. Otherwise, breeding the two would have resulted in a sterile species.
I don’t think they died off so much as interbred until there was only one population. Archaeologists and anthropologists say that the Neanderthal population never exceeded 100,000, and if the two groups mingled for 7000 years then the smaller group would simply have melted into the far larger group and woould leave traces of DNA in the descendants, like maybe the 4% or so that is reported.
When you put it that way, perhaps I was. I gave a bit too much consideration to the old "neanderthal" insult.
What can I say - I'm a small-brained Human. Or uninformed anyway.
God said Let us make ‘man’ in our image ... what? who is this us? no such thing bubbling raging reproducers pre-genesis...
Humans are literally some of the most sottish beings ever.
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