Vincenzo De Florio en Creative Writers, Biologia, Ciencia e Investigación, Biologists Geo-ICT engineer • VITO (Vlaamse Instelling voor Technologisch Onderzoek) 11/2/2018 · 3 min de lectura · 1,1K

A hypothesis in evolutionary biology


Many authors, starting with the classic work by Trivers and Willard, hypothesized the existence of “conditions” able to influence or control the sex of the offspring. Ever since the publication of that classic work, researchers have been producing an impressive amount of results that either bring evidence or contradict that hypothesis. This production has been chaotic to say the least, with scholars deriving their conclusions from “facts” ranging from dubious interpretations of microscope images to extremely serious mathematical and statistical models of the many organs and processes at play. I am merely an information scientist, lacking too many important pieces in this trans-disciplinary problem. But I have read several papers on this, and my focus on information led me to a simple observation: in information science, what is really important is the variation of the signal rather than the signal itself; in other words, it is a signal's variation that carries information -- it is a message -- while a steady signal it is not. As an example, a diet is a signal while a change in a diet, especially when it is a significant change – it is a message. Evidence corroborating this idea may be found in several works. Professor Elissa Cameron and her team, for instance, found out that, rather than glucose, it is the glucose gradient that might play a role in adjusting the offspring’s sex ratio in mice. This gradient represents a “message” from the environment, declaring the onset of a more favorable condition. (Dr. Cameron’s paper is available at https://www.researchgate.net/publication/5800238_Experimental_alteration_of_litter_sex_ratios_in_a_mammal.) The existence of “messages” of the opposite sign and outcome is also discussed by Professor Kristen Navara, who hypothesizes “a bias toward females during times of stress”, mediated by glucocorticoids in her very interesting paper “Programming of offspring sex ratios by maternal stress in humans” (https://www.researchgate.net/publication/44669486_Programming_of_offspring_sex_ratios_by_maternal_stress_in_humans_Assessment_of_physiological_mechanisms_using_a_comparative_approach). A stress / glucocorticoids-gradient signals in this case a time where an investment in a male offspring would not be advisable.

Testosterone gradients are another example. It is well known how such changes represent “boosts” that can lead to more daring behaviors. The late Dr. Valerie J Grant, in several articles (e.g. PMID: 20591970) and her book suggests that higher levels of testosterone might be associated with a higher sex ratio. Results are a little contradictory though, and I suspect that this might be due to measurements of the signal and not of its variations. Also it is not clear to me whether testosterone would have a causal role or rise “simply” as a side effect of some “first cause.”

Other examples of such gradients may be found in the huge bibliography of Dr. William H. James, who drew several hypotheses of endocrine mechanisms to control or influence the sex ratio.

Of course, if we assume that such messages are actually “there,” a logical question would be: Which type of messages are at play here? My answer comes from considering the theory of a fractal organization of the all – as one can find, for instance, the human body. The latter is composed of a primary unit "personifying" the whole – the brain – and a sophisticated hierarchy of organized systems, each of which is further composed of hierarchies of organized sub-systems. The overall functioning of the human body requires messages flowing from one end to the other, signaling actions that need to be taken when certain conditions are established; hormonal messages are a typical example of this large distributed organization.

My conclusion is then that mechanisms for the alteration of the gender of the offspring could possibly be formulated in terms of a distributed system of said messages. Perhaps a distributed system of fractally organized messages! Messages that is with a scope that ranges from the micro to the macro, signaling waves of actions that could "tune" our internal mechanisms after the external conditions expressed by the environment. In a number of my papers (e.g. here and here), I have suggested that said mechanism could be modeled, in sociotechnical systems, in terms of evolutionary game theory -- which I believe is very much in line with what had been theorized by Trivers and Willard. In fact, my conjecture is that particular messages from the “whole” (the brain) to the “parts” (the systems of organs) are meant to provide contextual information to the latter ones in order to adjust their local action in such a way as to favor a global condition matching the passed information. Local conditions favoring the birth of an offspring with an optimal evolutionary advantage are maybe the outcome of those messages. As a response, “thinner” messages would request the onset of other conditions of a “lesser” (hierarchical) scope. In this view, one could say that Dr. James' hypotheses characterize the endocrine nature of a "layer" of those messages.

As Dr. James himself expressed multiple times, the verification of an hypothesis such as mine would require the collaboration of many a specialist in domains I’m not acquainted with. I hope this short text may produce some interest and trigger exchange of ideas and chances for collaboration.

- Vincenzo De Florio, 2018-02-11

Article published also on LinkedIn.
A hypothesis in evolutionary biology


Vincenzo De Florio 14/2/2018 · #8

Interesting how this post of mine, now published on ARXIV, has received lovely comments on beBee while produced no reaction whatsoever on LinkedIn...

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Vincenzo De Florio 14/2/2018 · #7

I'm glad to be able to announce that "A hypothesis in evolutionary biology" is now on ARXIV!

https://arxiv.org/abs/1802.04257

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Vincenzo De Florio 12/2/2018 · #6

#5 I feel truly flattered of your consideration and blessed by your friendship dear friend -- thank you very much for your kindness, dear @Ali 🐝 Anani, Brand Ambassador @beBee!

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#4 Spontaneous reactions are maximized with release of energy and increase of entropy. Stable states are not therefore spontaneous within this frame of definition. More, is your brilliant observation stable signals offer very little or no information about the transmitter. Look at our healthy hearts and the variance in their heartbeat. You are a wonderful thinker my friend dear @Vincenzo De Florio

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Vincenzo De Florio 12/2/2018 · #4

#1 Thank you very much, dear @Ali 🐝 Anani, Brand Ambassador @beBee! I'd like to add that a stable signal that does not change much provides on the average very little information about the "transmitter". It is characterized by minimal entropy, that is. The opposite can be said of a message, which inherently carries information. The lovely book "A for Andromeda" by Fred Hoyle and John Elliot provide a fantastic example of this notion...
Again, many thanks for your kind words, dear friend!

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Vincenzo De Florio 12/2/2018 · #3

#2 Thank you very much @CityVP 🐝 Manjit for your brilliant comment. You made me think of something, dear friend. Humankind used to refer to nature as a mother. I think we have forgotten how true this verily is. Nature is a wise mother, and she has mechanisms to remove momentary lock-ins that for a while get the things stuck. I am personally convinced that either we change our courses and attitude of wayward sons or we shall be declared as incompossible and discarded. Female infanticide and sex-selective abortion are indeed dreadful dramas that tell of the absurd ways of our species, that shares of the angels but of the demons too.

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CityVP 🐝 Manjit 12/2/2018 · #2

Where these sex ratio's are important is in the skewing of that ratio through http://www.downtoearth.org.in/news/india-witnesses-one-of-the-highest-female-infanticide-incidents-in-the-world-54803 is sex-selection abortion and female infanticide. What would be interesting is if there is a fractal readdress that brings the ratio naturally back to 1.06 male to every 1.00 female. It is incredibly fascinating to ponder the long-term damage we as a human race do when we distort naturally occurring fractal patterns. It is a bit like pruning a tree in a way that is not natural to its fractal pattern. What we invariably get is a deformed and ugly tree. I am not saying that ugliness is a factor of fractal distortion, but that where humankind create selfish and egotistical imbalance, it would be interesting to know if there is a fractal mechanism over the long-term that brings natural balance to any man-made imbalance.

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"it is a signal's variation that carries information -- it is a message -- while a steady signal it is not:.

A n absolute shining buzz by DR. @Vincenzo De Florio. Deep thinking is invoked in this worthy buzz

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