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Selected Books by Edmund Blair Bolles

  • Galileo's Commandment: 2500 Years of Great Science Writing
  • The Ice Finders: How a Poet, a Professor, and a Politician Discovered the Ice Age
  • Einstein Defiant: Genius vs Genius in the Quantum Revolution

« Where Do We Stand with FOXP2? | Main | How Does Coevolution Work? »

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JanetK

The way genes are 'silenced' is part of what is called epigenetics. You will find the subject interesting. All our genes are found in all our cells but with different tissues, conditions, times during development etc, different sets of genes are used and transcribed at different rates. This gives RNA which is also edited, protected or destroyed before being used to make proteins or the other things that RNA does. There are a lot of mechanism and new ones being discovered.
Metaphor: There are a lot of books in the library but that doesn't mean they are all being read all the time by everybody or even that some are not in the stacks in the basement and read by no one.
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BLOGGER: Yes, epigenetics is the hot topic. But its role in selection and Hamilton's equation (which is purely focused on genes) is not yet clear to me.

Sociogenomics.wordpress.com

Thank you for the thoughtful commentary on some of the issues presented in the paper. Imprinted genes (a small portion of the genome) do exist and violate some of the basic laws of inheritance. Imprints are placed on DNA in the gametes (sperm or egg) and are erased when the offspring produces its own gametes. Imprinting is an example of an epigenetic effect. The gene has a 'memory' of where it was in previous generation (i.e., in an egg or sperm).

For papers detailing the mechanisms (e.g., DNA methylation) I suggest www.geneimprint.com Beyond containing great references on genomic imprinting, a list of confirmed cases of imprinted genes is provided on the website and whether or not they are expressed paternally or maternally. The existence of imprinted genes is
not in dispute; however, whether or not kinship theory is the best
evolutionary explanation for the expression patterns of imprinted genes is under some debate. Many scientists feel that kinship theory (aka parental antagonism or conflict theory) is the best theory for genomic imprinting.
Some scientists disagree (which is healthy). Below are two references from David Haig's website that explain quite well the current state of the evidence on the topic. There is an active area of research on the epigenetic mechanisms of imprinting.

The parental antagonism approach to language evolution is in its infancy, but inherently testable. Specifically, we can study if language-associated genes when maternally-expressed in children are responsible for more cooperative forms of linguistic behaviour (e.g., transmission and reception of sibling sharing norms); and if language-associated genes when paternally-expressed in
children produce more selfish forms of linguistic behaviour (e.g., increasing demands on mother's parental investment). Chimeric mouse models will likely make the biggest strides with regards to experimental rigour in the study of imprinted genes involvement in mammalian communication; however imprinted genetic disorders in humans will continue to be a rich source of information on communicative behavioural phenotypes important in language development.

REFERENCES

Haig, D. (2004) Genomic imprinting and kinship: how good is the evidence? Annual Review of Genetics 38: 553-585.

http://www.oeb.harvard.edu/faculty/haig/Publications_files/04Evidence.pdf

Wilkins, J. F. & Haig, D. (2003) What good is genomic imprinting: the function of parent-specific gene expression. Nature Reviews Genetics 4:359-368.

http://www.oeb.harvard.edu/faculty/haig/Publications_files/03WhatGood.pdf

Best wishes, Will Brown

Jerry Moore

The Linguistic twist of imprinted genes “theory” could be valid if it applies to human biology only. This theory is irrelevant to linguistic issue if birds or monkeys possess the same mechanisms.

Sociogenomics.wordpress.com

Jerry Moore is simultaneously 'right' and 'wrong' in the post above. 'Right' in that if Brown's (2011) parental antagonism of imprinted genes hypothesis for language is a useful approach it should be able to explain why language appears to be a human specialisation (i.e., not present in other species). Nonetheless, to fully understand language Nobel Laureate Niko Tinbergen's four interwoven causes must be used. Note that these different explanations are not alternative hypotheses to one another but are all part of a full explanation of the causes of behaviour: (a) Proximate causes (e.g., gene expression, neurochemistry, neural structure, environmental causes of human language); (b) Ontogenetic causes (e.g., socialisation, culture, developmental phases causing human language); (c) Phylogenetic causes (e.g., the ancestral communicative precursors to human language); and (d) Ultimate causes (e.g., how human language genes accrued ancestral fitness advantages mediating their spread through ancestral populations). It should be clear from the above intertwined causes that the study of communication in non-human animals is critical to understanding language evolution. Specifically, we can infer evolutionary precursors when we study communication and its underlying correlates in other species. I am sure Jerry Moore would agree.

Brown's (2011) hypothesis is that human language shares early developmental communicative correlates with other mammalian species (i.e., communicative matrigenes in offspring are maternal demand reducers and patrigenes are maternal demand enhancers). However, the more unique aspects of human language (e.g., linguistic social norms of sharing within highly maternally related groups) are mediated by communicative matrigenes in offspring that are hypothesised to enhance matrilineal inclusive fitness. Brown (2011) has already showed that the similarity between humans and chimps in overlapping regions of matrigenes are significantly different; but not the overlapping regions of patrigenes.

Nonetheless, I also suspect that matrigene-patrigene cooperation within offspring genomes was particularly important during human evolution. I am currently working on a new paper that will attempt to explain why evolutionarily-speaking, matrigenes and patrigenes started to 'cooperate' within the genomes of human children (but not other mammalian offspring). I will be making use of two interesting aspects of supposed human uniqueness: (1) humans have shorter inter-birth intervals (compared to chimpanzees) with older offspring helping mother forage for supplemental foods; and (2) humans have culturally-variable sex-biased dispersal patterns. One possibility is that the coevolutionary conflicts between parental genomes intensified early and was latter resolved over hominin evolutionary history. I am currently sketching out ways to test this idea that matrigene-patrigene cooperation was important for the evolution of human cultural and language capacities.

Best wishes, Will Brown

Jerry Moore

“The evolution of human cultural and language capacities” is synonymous for the evolution of capacities for conscious conduct. Development of the specie unique signalling communicative capacity could be more realistic (less biologically complicated) result for such genetic changes. I believe you are going keep this in focus.

Sociogenomics.wordpress.com

I certainly do not think cultural transmission or language capacities are synonymous with consciousness. My guess is that the abilities to culturally acquire behaviour, signal and transmit human language, and human consciousness all evolved separately to solve different adaptive problems. Nonetheless, these distinct capacities likely became co-adapted over time (although I am not entirely focused on that possibility at the moment). I am interested in the topic of reliable and deceptive signalling in nature and how these models can help elucidate language evolution. The coevolutionary arms races between reliable and deceptive signallers should be kept at the forefront of language evolution models. Dialects, shibboleths and other forms of coalitional badges seem particularly relevant for human language. My suspicion is that dialects, shibboleths etc. evolved in a collateral kin context whereby benefits accrued much like an immune system detects self from other. Intragenomic conflicts over the transmission and reception of social information are expected to have influence at multiple levels of biological organisation(intrapersonal, interpersonal, intragroup etc).
Best wishes, Will Brown

Jerry Moore

It is intriguing to know what is the conscious activity is without any linguistic or cultural context and what is the human language or culture not being involve in the conscious activity process.
Don’t you think, we are going back in discussion on creatures like “human with no Language” or “human with no Consciousness” by apposing Second Signal System theory? http://www.springerlink.com/content/7342577504067716/
Best Wishes, JM.

JanetK

Jerry Moore, do you have any evidence of consciousness requiring language or culture? I don't mean linguistic theories or philosophical logic etc. but actual scientific experimental evidence. If you do, I would appreciate references as I have not found any. Ditto if you have any evidence that no animals are conscious (other than humans).There may be language without consciousness but it is doubtful. However there certainly, on the face of it, seems to be consciousness without language. The neurological signs of consciousness appear in some animals.

Jerry Moore

JanetK, you wrote “the neurological signs of consciousness appear in some animals”. Conscious activity or meaningful act cannot be explored without any involvement of the human-centric judgment. Even simple explanations of zones activity in the animal brain scan, when done by human. Philosophy isn’t useless. It stays at foundation of all sort of knowledge and it is reflected in your healthy doubts - “There may be language without consciousness but it is doubtful”.

Jerry Moore

JanetK, please try this paper. Now it is submitted in part1 & part2.
Something is better then nothing.
Check its ref-s.
http://philpapers.org/rec/MORSP-2

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