Talk:Evolution of the brain

Please see

There is a related discussion at Wikipedia talk:WikiProject Neuroscience#Brain size and Human brain size. --Tryptofish (talk) 20:07, 8 September 2014 (UTC)

Genetic Factor contributing to modern evolution

Bruce Lahn, the senior author at the Howard Hughes Medical Center at the University of Chicago and colleagues have suggested that there are specific genes that control the size of the human brain. These genes continue to play a role in brain evolution, implying that the brain is continuing to evolve. The study began with the researchers assessing 214 genes that are involved in brain development. These genes were obtained from humans, macaques, rats and mice. Lahn and the other researchers noted points in the DNA sequences that caused protein alterations. These DNA changes were then scaled to the evolutionary time that it took for those changes to occur. The data showed the genes in the human brain evolved much faster than those of the other species. Once this genomic evidence was acquired, Lahn and his team decided to find the specific gene or genes that allowed for or even controlled this rapid evolution. Two genes were found to control the size of the human brain as it develops. These genes are Microcephalin and Abnormal Spindle-like Microcephaly (ASPM). The researchers at the University of Chicago were able to determine that under the pressures of selection, both of these genes showed significant DNA sequence changes. Lahn's earlier studies displayed that Microcephalin experienced rapid evolution along the primate lineage which eventually led to the emergence of Homo sapiens. After the emergence of humans, Microcephalin seems to have shown a slower evolution rate. On the contrary, ASPM showed its most rapid evolution in on the later years of human evolution once the divergence between chimpanzees and humans had already occurred. Dorus S., Vallender E.J., Evans P.D., Anderson J.R., Gilbert S.L., Mahowald M., Wyckoff G.J., Malcolm C.M., Lahn B.T. 2004. Accelerated evolution of nervous system gene in the origin of homosapiens. Cell. 119(7):1027-40.

Each of the gene sequences went through specific changes that lead to the evolution of humans from ancestral relatives. In order to determine these alterations, Lahn and his colleagues used DNA sequences from multiple primates then compared and contrasted the sequences with those of humans. Following this step, the researchers statistically analyzed the key differences between the primate and human DNA to come to the conclusion, that the differences were due to natural selection. The changes in DNA sequences of these genes accumulated to bring about a competitive advantage and higher fitness that humans possess in relation to other primates This comparative advantage is coupled with a larger brain size which ultimately allows the human mind to have a higher cognitive awareness. Evans P.D., Gilbert S.L, Mekel-Bobroz N., Vallender E.J., Anderson J.R. Vaez-Azizi L.M., Tishkoff S.A., Hudson R.R. and Lahn B.T. 2005. Microcephalin, a Gene Reulating Brain Size, Continues to Evolve Adaptively in Humans. Science 309(5741):1717-20. — Preceding unsigned comment added by Solanki.15 (talk • contribs) 20:55, 17 November 2014 (UTC)

Missing sources in part 1

There are two sources mentioned in part 1: ´´Hoffman et al. 2004´´ and ´´Hofman 2001´´, but they are not quoted in a section literature or similar. Quite difficult to find the sources without being the author of this wikipedia article. DinoDinoDinoDinoDino (talk) 11:12, 10 December 2014 (UTC)

Frugivorous?

A couple of days ago MisterSheik (talk · contribs) made an edit that changed "fruit eating" to "frugivorous", with no edit summary. I undid the edit, with edit summary "no reason to use an obscure technical term here". The editor reverted back, with edit summary "it's not technical :) use a dictionary if you don't know it". It seems to me that if I, with a Ph.D. in biology, struggle to remember the meaning of the word, it is probably not suitable for Wikipedia's broad audience, and really only serves to show off how erudite we Wikipedians are. But my personal policy is never to multi-revert, so I will leave it up to other editors to decide how to proceed. Looie496 (talk) 03:05, 10 February 2015 (UTC)

There are more brains than HUMAN BRAINS, more even than VERTEBRATE BRAINS

This page is a mess. Amateurish, with no grasp whatsoever of brain development even in chordates. No coverage at all of early development in bilaterians generally,including insects which is what I came for. Needs a total rewrite by a specialist. A complete Wikicockup.68.178.50.46 (talk) 22:27, 23 July 2015 (UTC)

Wikipedia relies on volunteer efforts. Unfortunately not very many academic specialists are prepared to volunteer their work; as a result many articles about specialized academic topics are poor in quality. Improvements are always welcome. Looie496 (talk) 18:46, 24 July 2015 (UTC)

OK glad someone said it, this is just...awful. Very vertebro-centric, which is frankly completely unjustified for an article on evolution. There are lots of non-vertebrate brains. The first brains were not in worms, as the article states, but in other invertebrate species like starfish or jellyfish. If I ever get time I will research this and try to help fix it, but...wow. I think nothing, i.e., a blank page, would be better than this page as it stands.

I agree. At a minimum Human Brain Evolution should be a separate article, with a link to it in this article. This article can't decide what the actual topic is. — Preceding unsigned comment added by 198.177.6.251 (talk) 15:43, 17 May 2017 (UTC)

Brain and eyes

It is about never noticed that eyes and brains are developed about the same time by the same creatures.

I ask myself if the brain is not created as a function of processing eye input and then later developed doing other things? Isen't this question for an expert to develop at this page. One would as a reader like to know, --Zzalpha (talk) 17:40, 13 January 2020 (UTC)

Section "Randomizing access and scaling brains up"

I would suggest removing this section. The text is incomprehensible, and includes mostly esoteric and speculative content that is not back up by citations. The citations at the end of the section are only vaguely related to the content.

For example the sentence "Some scientists argue that this difference is due to vertebrate and cephalopod neurons having evolved ways of communicating that overcome the scalability problem of neural networks while most animal groups have not" introduces the concept of a 'scalability problem of neural networks" without any backing up by citations. Furthermore, the part "neurons having evolved ways of communicating that overcome the scalability problem" is incomprehensible.

As far as I can see, the citations at the end of the section are not backing up the the claims in the section. Chen et al. (2015) is an article about microRNAs in brain evolution but makes no mention of the 'randomized access' that is described in the section. Ferrante et al. (2016) is an article that describes a model of evolution of brain parcellation and does not mention the concept 'randomized access' either. --Vincentvega7777 (talk) 19:45, 8 October 2020 (UTC)

References

Auto correct or error in early history

It says:

"Fossilization of brain, or other soft tissue, is possible however, and scientists can infer that the first brain structure appeared at least 1 minute ago, with fossil brain tissue present in sites of exceptional preservation."

It definitely shouldn't be "1 minute ago" but I don't know what it should be. Could someone with greater knowledge on this topic please correct this? 2600:1700:40A0:7E10:C00E:3AEF:CA34:2CFE (talk) 02:14, 14 April 2022 (UTC)

"At least 1 day ago"

Really? 2603:9001:3607:C52:A38A:9858:9607:7EAE (talk) 09:26, 2 September 2022 (UTC)

Conclusion

Jk 103.235.2.194 (talk) 17:36, 11 December 2022 (UTC)

Please add info on "HAQERs" to the "Genetic factors" section

Please add some info on/from this study to the section "Genetic factors of recent evolution". It's featured in 2022 in science more or less like so:

Geneticists report that the fastest-evolved regions of the human genome, they call "human ancestor quickly evolved regions" (HAQERs), "rapidly diverged in an episodic burst" of positive selection prior to the human-Neanderthal split and identify over 1,500 such HAQERs that substantially distinguish humans from related other apes via datasets such as of "human accelerated regions" (HARs) and experiments that use embryonic mouse brains.

Please clarify the tagged issues and try to make it a bit clearer (you could use and extend this text).

Please elaborate for example what is meant with 'recent episodic burst' and how these changes are particularly notable or impactful or what makes them characteristic (e.g. "quickly evolved" and what that means) etc

I think it could go into a new subsection which could even be at the top of the section. Unlike the other subsections it's not a specific functionality-specific change but a larger set of recent genetic differences and I'm not sure how the section should get named. One should also note that changes before the human-Neanderthal split may not be (considered) "recent" and more relevant to articles like Evolution of human intelligence and Human evolution#Divergence of the human clade from other great apes.

Also the section "MCPH1 and ASPM" seems a bit long and it would be good if somebody could shorten it or add subheaders to it. (A) longer version(s) could still be in the articles for these two genes.

References

Prototyperspective (talk) 09:41, 1 February 2023 (UTC)