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尼安德特人之所以灭绝是因为他们的眼睛比现代人类大

本帖最后由 198401 于 2013-3-18 11:43 编辑

http://www.bbc.co.uk/news/science-environment-21759233
Neanderthals' large eyes 'caused their demise'

By Pallab Ghosh

A study of Neanderthal skulls suggests that they became extinct because they had larger eyes than our species.

As a result, more of their brains were devoted to seeing in the long, dark nights in Europe, at the expense of high-level processing.

By contrast, the larger frontal brain regions of Homo sapiens led to the fashioning of warmer clothes and the development of larger social networks.

The study is published in Proceedings of the Royal Society B.

Neanderthals are a closely related species of human that lived in Europe from around 250,000 years ago. They coexisted and interacted briefly with our species until they went extinct about 28,000 years ago, in part due to an ice age.

The research team explored the idea that the ancestor of Neanderthals left Africa and had to adapt to the longer, darker nights and murkier days of Europe. The result was that Neanderthals evolved larger eyes and a much larger visual processing area at the backs of their brains.

The humans that stayed in Africa, on the other hand, continued to enjoy bright and beautiful days and so had no need for such an adaption. Instead, these people, our ancestors, evolved their frontal lobes, associated with higher-level thinking, before they spread across the globe.

Eiluned Pearce of Oxford University decided to check this theory. She compared the skulls of 32 Homo sapiens and 13 Neanderthals.
Social networks

Ms Pearce found that Neanderthals had significantly larger eye sockets - by an average of 6mm from top to bottom.

Although this seems like a small amount, she said that it was enough for Neanderthals to use significantly more of their brains to process visual information.

"Since Neanderthals evolved at higher latitudes, more of the Neanderthal brain would have been dedicated to vision and body control, leaving less brain to deal with other functions like social networking," she told BBC News.

This is a view backed by Prof Chris Stringer, who was also involved in the research and is an expert in human origins at the Natural History Museum in London.

"We infer that Neanderthals had a smaller cognitive part of the brain and this would have limited them, including their ability to form larger groups. If you live in a larger group, you need a larger brain in order to process all those extra relationships," he explained.

The Neanderthals' more visually-focused brain structure might also have affected their ability to innovate and to adapt to the ice age that was thought to have contributed to their demise.

Neanderthal wraps

There is archaeological evidence, for example, that the Homo sapiens that coexisted with Neanderthals had needles that they used to make tailored clothing. This would have kept them much warmer than the wraps thought to have been worn by Neanderthals.

Prof Stringer said that all these factors together might have given our species a crucial advantage that enabled us to survive.

"Even if you had a small percent better ability to react quickly, to rely on your neighbours to help you survive and to pass on information - all these things together gave the edge to Homo sapiens over Neanderthals, and that may have made a difference to survival."

The finding runs counter to the idea that Neanderthals were not the stupid, brutish creatures portrayed in Hollywood films; they may well have been as intelligent as our species.

Oxford University's Prof Robin Dunbar, who supervised the study, said that the team wanted to avoid restoring the stereotypical image of Neanderthals.

"They were very, very smart, but not quite in the same league as Homo sapiens," he told BBC News.

"That difference might have been enough to tip the balance when things were beginning to get tough at the end of the last ice age," he said.

Up until now, researchers' knowledge of Neanderthals' brains has been based on casts of skulls. This has given an indication of brain size and structure, but has not given any real indication of how the Neanderthal brain functioned differently from ours. The latest study is an imaginative approach in trying to address this issue.

Previous research by Ms Pearce has shown that modern humans living at higher latitudes evolved bigger vision areas in the brain to cope with lower light levels. There is no suggestion though that their higher cognitive abilities suffered as a consequence.

Studies on primates have shown that eye size is proportional to the amount of brain space devoted to visual processing. So the researchers made the assumption that this would be true of Neanderthals.


The eyes have it: The Neanderthal skull (L) has larger eye sockets compared with a modern human skull (R). Consequently, the now extinct species used more of its brain to process visual information

Neanderthals were close evolutionary cousins of our own species, Homo sapiens
New insights into differences in brain organization between Neanderthals and anatomically modern humans

Eiluned Pearce etc.

Abstract

Previous research has identified morphological differences between the brains of Neanderthals and anatomically modern humans (AMHs). However, studies using endocasts or the cranium itself are limited to investigating external surface features and the overall size and shape of the brain. A complementary approach uses comparative primate data to estimate the size of internal brain areas. Previous attempts to do this have generally assumed that identical total brain volumes imply identical internal organization. Here, we argue that, in the case of Neanderthals and AMHs, differences in the size of the body and visual system imply differences in organization between the same-sized brains of these two taxa. We show that Neanderthals had significantly larger visual systems than contemporary AMHs (indexed by orbital volume) and that when this, along with their greater body mass, is taken into account, Neanderthals have significantly smaller adjusted endocranial capacities than contemporary AMHs. We discuss possible implications of differing brain organization in terms of social cognition, and consider these in the context of differing abilities to cope with fluctuating resources and cultural maintenance.

http://rspb.royalsocietypublishing.org/content/280/1758/20130168
眼睛大通常表示夜视能力强
物变天汰,余者生存
依然不够说服力,正如文中所说“Up until now, researchers' knowledge of Neanderthals' brains has been based on casts of skulls. This has given an indication of brain size and structure, but has not given any real indication of how the Neanderthal brain functioned differently from ours. The latest study is an imaginative approach in trying to address this issue.”
而且这些欧洲人显然忽视了中东的尼人比同时期的克罗马农人更具组织性(或者更文明)的事实。
我怀疑现在欧洲人始终难以接受克人与尼人之间残酷的‘禅代’真相,总是想从达尔文的进化论方面寻求一些貌似合理的依据,于是一些学者的‘假说’应运而生,其中就包括这位女性学者领导的研究小组。
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
依然不够说服力,正如文中所说“Up until now, researchers' knowledge of Neanderthals' brains has been based on casts of skulls. This has given an indication of brain size and structure, but has not give ...
imvivi001 发表于 2013-4-29 15:25
中东尼人比克罗马农人更有组织性的依据是?
O3a3c* (M134+, M117-)
貌似尼人始终没发展出弓箭,标枪之类的远射武器.
物变天汰,余者生存
中东尼人比克罗马农人更有组织性的依据是?
hercules 发表于 2013-4-30 17:09
from wikipedia:
Neanderthals made advanced tools,[55] had a language (the nature of which is debated) and lived in complex social groups. The Molodova archaeological site in eastern Ukraine suggests some Neanderthals built dwellings using animal bones. A building was made of mammoth skulls, jaws, tusks and leg bones, and had 25 hearths inside.[56]
   new studies indicate Neanderthals had cooked vegetables in their diet.[60][61] In 2010, a U.S. researcher reported finding cooked vegetable matter in the teeth of a Neanderthal skull, contradicting the earlier belief they were exclusively (or almost exclusively) carnivorous[57] and apex predators.[59][60]       另外我之前曾经找到一篇论述中东尼人墓地普遍有花粉孢子痕迹的论文,文中提示中东尼人可能已经有为墓地献花仪式(或他们喜欢挑选鲜花盛开的地方作为墓地),记得当时曾经与saha讨论过。这一切都是同时期的欧洲克罗马农人所不具备的。
物格而后知至,知至而后意诚,意诚而后心正,心正而后身修,身修而后家齐,家齐而后国治,国治而后天下平...
from wikipedia:
Neanderthals made advanced tools,[55] had a language (the nature of which is debated) and lived in complex social groups. The Molodova archaeological site in eastern Ukraine sugges ...
imvivi001 发表于 2013-5-7 18:29
这个和组织性搭不上。
O3a3c* (M134+, M117-)
墓葬文化的出现说明更珍惜人的价值,可以暗示组织性的
也许只是生殖力的强弱,看看现在的黑人移民
貌似尼人始终没发展出弓箭,标枪之类的远射武器.
谜雾 发表于 2013-5-4 10:01
海德堡人就有标枪了,尼人怎么会没有?至于弓箭,智人貌似也是在冰河期之后才发展出来的。就技术水平而言,智人作为物种没有比尼人高出一个档次
海德堡人就有标枪了,尼人怎么会没有?至于弓箭,智人貌似也是在冰河期之后才发展出来的。就技术水平而言,智人作为物种没有比尼人高出一个档次
印欧遭遇匈奴 发表于 2016-4-15 12:23
没听说海德堡人有标枪,只是长矛吧
物变天汰,余者生存
本帖最后由 baiyueren 于 2016-5-5 11:59 编辑
另外我之前曾经找到一篇论述中东尼人墓地普遍有花粉孢子痕迹的论文,文中提示中东尼人可能已经有为墓地献花仪式(或他们喜欢挑选鲜花盛开的地方作为墓地),记得当时曾经与saha讨论过。这一切都是同时期的欧洲克罗马农人所不具备的。
imvivi001 发表于 2013-5-7 18:29
据研究,尼人是有在死者尸体周围撒赤铁矿粉和献花的习惯。这说明他们有了初步的抽象思维的能力,但与组织性无关。而当时的克罗马农人却有着表现史前动物的岩洞壁画,以及肥胖的维纳斯小雕像的东西,可能与生殖崇拜有关,不排除已经出现原始宗教的可能性。所以我认为在抽象思维方面来说,尼人和克人的发展水平根本不可同日而语。
NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
本帖最后由 baiyueren 于 2016-5-5 11:43 编辑

我认为主贴的观点非常片面可笑:因为眼睛大,所以视觉中枢大,所以挤占了大脑其他部分的发育,所以智力低下??实际上,智力水平主要取决于大脑皮层的进化水平而不是脑容量,尼人的脑容量达到1500ml以上,但还是没现代人聪明。
NRY: O2a1c1a1a1a1a1a1-002611,F11,F17,F856,F1495(源自粤西云浮)
mtDNA:B4d1(源自浙北慈溪)
百越人的人类学文集 http://blog.sina.com.cn/baiyueren
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