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Euclides
Sunday, June 13th, 2004, 04:13 PM
Nature. 2004 Apr 29;428(6986):936-9.

Comment in:
Nature. 2004 Apr 29;428(6986):904-5.

Surprisingly rapid growth in Neanderthals.

Ramirez Rozzi FV, Bermudez De Castro JM.

UPR 2147, Dyamique de l'Evolution Humaine, CNRS, 44, Rue de l'Amiral Mouchez, 75014 Paris, France. ramrozzi@ivry.cnrs.fr

Life-history traits correlate closely with dental growth, so differences in dental growth within Homo can enable us to determine how somatic development has evolved and to identify developmental shifts that warrant species-level distinctions. Dental growth can be determined from the speed of enamel formation (or extension rate). We analysed the enamel extension rate in Homo antecessor (8 teeth analysed), Homo heidelbergensis (106), Homo neanderthalensis ('Neanderthals'; 146) and Upper Palaeolithic-Mesolithic Homo sapiens (100). Here we report that Upper Palaeolithic-Mesolithic H. sapiens shared an identical dental development pattern with modern humans, but that H. antecessor and H. heidelbergensis had shorter periods of dental growth. Surprisingly, Neanderthals were characterized by having the shortest period of dental growth. Because dental growth is an excellent indicator of somatic development, our results suggest that Neanderthals developed faster even than their immediate ancestor, H. heidelbergensis. Dental growth became longer and brain size increased from the Plio-Pleistocene in hominid evolution. Neanderthals, despite having a large brain, were characterized by a short period of development. This autapomorphy in growth is an evolutionary reversal, and points strongly to a specific distinction between H. sapiens and H. neanderthalensis

Agrippa
Sunday, June 13th, 2004, 04:53 PM
This autapomorphy in growth is an evolutionary reversal, and points strongly to a specific distinction between H. sapiens and H. neanderthalensis

Another point, which I knew, but didnt knew that the differences are so big, for my convinction that the neanderthalensis didnt contributed to the modern sapiens populations of Europe.

Furthermore that they are more likely to be considered as an distinct species.

I have the impression, no the conviction, that the classical Neandertalids evolved in a non-human way.
What does that mean?

After the Australopithecus populations died out, niche-specialization was never present in a way like it was in Australopithecus robustus.
The advantageous features in general were prefered, mainly large brain, omnivorous, mobile, manipulation of the environment etc.

Thats was true for almost all populations afterwards, but ESPECIALLY for H. sapiens.

The Neanderalids on the other hand were from my perspective a total niche-specialization in a "mainly physical" adaptation more than environmental manipulation.
Maybe that was necessary because of the extreme conditions, their subsistence and small group organization.

They adapted their body away from a generalist, to a specialist.

I would even compare that difference between H.s. and H.n. with the difference between Reptiles/Dinosaurs with higher developed mammals.

The first just developed physcial advantageous features, the second a bigger brain, more flexible behaviour.
A generalized specialization with flexible behaviour almost always wins on the long run.

That together with the low birthrate was the reason classical Neandertalids disappeared.

I really doubt that their brain was as developed and effective as that of H.s., even if it was slightly bigger. They were just made to be as soon as possible mature and for survive in small groups, even alone, because of the extreme conditions.

Such "humans" can be compete with good organized, creative and in big groups hunting populations.

Maybe they can in their niche, but even there not if the new ones adapt the material culture, and for sure not if the climate changes to something which is much worse for their negative over-specialization.
I think that even the structures of the brain are very different from that of H.s. If we would be able to reproduce it, we will see, and what we know from the skulls goes in that direction as well.

Rodskarl Dubhgall
Monday, June 14th, 2004, 12:27 AM
That together with the low birthrate was the reason classical Neandertalids disappeared.Now you know that Europa is indeed troubled. Check the birthrates, bucko! I believe that in order for monotheists to assert their beliefs, they push for people to believe that only in Africa did humanity originate. I am in favor of the multi-region explanation. I believe polytheism has its merits, in the fact, to me, that Neanderthals were the precursors to European peoples.

Agrippa
Monday, June 14th, 2004, 01:43 AM
Now you know that Europa is indeed troubled. Check the birthrates, bucko! I believe that in order for monotheists to assert their beliefs, they push for people to believe that only in Africa did humanity originate. I am in favor of the multi-region explanation. I believe polytheism has its merits, in the fact, to me, that Neanderthals were the precursors to European peoples.

Maybe my point of view is influenced by ideology, but yours even more so.

You that issue from the wrong perspective. Europids are more progressive than Neandertalids, Negrids arent better adapted to Europe than Europids.

Europids would be superiour, the only reason why they may disappear is their idiotic culture at the moment and contraselection.
Thats the only reason why Negrids can spread themselves and Europeans lose.

Its a total different situation to that of Neandertalids to Europids.

Rodskarl Dubhgall
Monday, June 14th, 2004, 01:47 AM
Different stages of evolution, my friend...

Agrippa
Monday, June 14th, 2004, 02:16 AM
Different stages of evolution, my friend...

Neandertalids are a negative niche-specialization with no future on the long run.

Europids are progressive sapiens variants.

Negrids are a tropical race, not made for Europe, strongly specialiized for the tropic regions, even more than the early sapiens types.
They are not progressive and not in any way superiour to Europids, especially not in the temperate climate.

You cant compare such totally different situations.

Rodskarl Dubhgall
Monday, June 14th, 2004, 02:18 AM
Climate changes have occured, and techno-advances have allowed this dispersal...Man has brought this upon himself as a result of evolution. Neanderthals burnt themselves out and so will we...