Posts tagged evolution

The Eight Rasas (aesthetic essences)

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According to Indian Aesthetics , as outlined in Bharat Muni’s Natyashatra,  there are eight Rasas or impacts that an aesthetic piece of work like dance form/ literary piece, tries to achieve/invoke in the beholder/reader. These can be loosely thought of as eight different kinds of aesthetic experiences.

 

As is evident I like all things eight, as I believe they have an underlying eight fold evo-devo stage structure behind them.  In this case in visual art from each of the rasa is associated with a predominant color that signifies that rasa. For eg Shringar or Love/beauty/erotic rasa has as its color, color green.

 

Now, I have also blogged previously about color terms and how they may have evolved in an eight step model. In brief, I believe that Black came first , white next, then Red followed; after which followed yellow, blue and green and then other terms like orange, brown and grey followed.  This I believe is also tied to the way our color vision and sensitivity would have grown/evolved.

 

Taking cue from that color term evolution model , I belive the eight rasas evolved in the same order as the color used to denote them, and that nicely fits with other aspects of the eight stage theory too, like the eight stage emotion development.

 

So, in essence, please find listed below the eight Rasaas in the correct eight stage order:

1. Bahyanak Rasa: color Black : emotion fear.

2. Hasya Rasa: color white: emotion joy/laughter

3. Rudra Rasa: color red : emotion anger

4. Adbhuta Rasa: color yellow , emotion wonder

5. Bibhitsa Rasa: color blue, emotion disgust

6. Shringar rasa: color green; emotion erotic/love

7. Veera rasa : color orange; emotion heroism

8. Karuna rasa: color grey; emotion compassion/ sadness.

 

Contrast this with the basic emotions list I have come up earlier viz.
1. Fear – Bahyanak
2. Joy/happiness – Hasya
3. Anger – Raudra
4. Sadness – Karuna
5. Disgust – Bibhitsa
6. Surprise – shringar
7. Contempt – Veera
8. Interest (anticipation) – Adbhuta

 

With just one switch between the Adbhuta (wonder/interest) and Karuna (sadness/ compassion), the eight rasas fit both the color term evolution and basic emotions evolution. That surely means we are at something and moving in the right direction as different routes are leading to the same destination. .

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The four mechanisms of evolution

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Regular readers of the blog will know of my enthusiasm for evolutionary and developmental theories especially the eight stage evo-devo theory.

I have also advocated the four primary problems faced by all creatures undergoing evolution, as delineated by Theodore Millon- the problems of Existence; Adaptation; Replication and Abstraction which lead to polarities of pain/pleasure;  active/passive; self/other and broad/narrow at each of the stages/domains/ solutions.

However, when we pause to look at what the mechanism of evolution actually is, we clearly note that there are a few prerequisites for evolution to take place and unless all the four mechanisms/ preconditions are present it is unlikely that the creatures will evolve.   I have been having this in the back of my mind for quite some time especially as I  have been ruminating on the BVSR (blind variation and selective retention)  theory of Donald Campbell as applied to creativity.

I was recently reading ‘Driven’ and in that book too a lot of emphasis is placed on the V-S-R (Variation, Selection, Retention) mechanism of evolution. I think this popular portrayal of evolution misses another important ingredient required for evolution that of Struggle due to limited resources and excess fecundity. If the problem of limited resources and excess fecundity was not there, probably there would be no pressure to evolve.

 

Thus I would like to frame the four evolutionary prerequisites/ mechanisms as Struggle-Retention- Variation-Selection or S_R_V_S.  To elaborate:

1. Struggle: This is driven by the fact of limited resources and overproduction due to excess fecundity. Here two strategies, leading to 2 polarities,  work; one can either compete for resources or one can cooperate and exist symbiotically.  Also, one can either have a r-strategy (low investment in many) of reproduction or A K-strategy (high investment in few). In the eight stage model, the organisms at first 2 levels would be primarily constrained by this evolutionary mechanisms.

2. Retention:  There must exist some mechanism by which the traits that confer survival/reproductive or selection advantage can be retained over time in the same individual and over generations in the same species. Again the mechanism of stable trait over time as well as  over generations may be in conflict with each other and may lead to a polarity. Creatures at stage 3 and 4 of 8 stage evo-devo theory would likely face issues regarding stability and retention of traits; retaining in individual the same trait is an active process; while retaining in generations is more passively driven.

3. Variation. There must exist some  mechanism that causes minor changes in the stable traits such that variation may lead to deleterious or beneficial effect over the individual having that variation. This is classically implemented using mutations and sexual-recombinations. While mutations confer (dis)advantages at an individual level; recombinations take that to the next level by affecting offsprings variability. The creatures at stages 5 and 6 of evo-devo stages are grappling with these problems of adequate variation in self and other.

4. Selection: There must exist some selection criteria based on which the struggling creatures having stable but slightly varying traits can be selected for or against.  While Natural selection (stage 7) employs the three methods of directional, stabilizing and disruptive selection; the stage 8 deploys a qualitatively different method of sexual selection where the criteria for selection may be  arbitrarily driven by choices of the other gender conspesifics.  While the Natural selection criteria is broad, the sexual selection criteria can be said to be narrow. Another way to look at this is that the selection crteria is either to survive (natural selction) or to reproduce (sexual slection) and those who are sucessful can very well move from one level/species to another (speciation due to sexual selection).

To me this is further  corrobrating evidence of the eight stage evo-devo theory and ABCD model being on the right track.

 

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The Four Fundamental Causes

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This post is an ambitious attempt to link the four causes delineated by Aristotle, to the four questions asked by Tinbergen to the four types of explanations that can be made for any human/animal ability.

First a bit of a background.

Aristotle had listed four causes – Material,  Efficient, Formal and Final causes. From the Wikipedia:
Aristotle held that there were four kinds of causes:

  • A thing’s material cause is the material of which it consists. (For a table, that might be wood; for a statue, that might be bronze or marble.)
  • A thing’s formal cause is its form, i.e. the arrangement of that matter.
  • A thing’s efficient or moving cause is “the primary source of the change or rest.” An efficient cause of x can be present even if x is never actually produced and so should not be confused with a sufficient cause.(Aristotle argues that, for a table, this would be the art of table-making, which is the principle guiding its creation.)
  • A thing’s final cause is its aim or purpose. That for the sake of which a thing is what it is. (For a seed, it might be an adult plant. For a sailboat, it might be sailing. For a ball at the top of a ramp, it might be coming to rest at the bottom.)

While studying these causes scholars have stressed on two sorts of distinctions, the first is the concept of actuality and potentiality- while some causes like the final cause (teeos or entelchiea) and formal cause (eidos or energiea) are actual; the material cause is deemed to be poetntial.

The other concept is that of Hylomorphism, or the distinction between matter and form. I believe that the four causes can be broken down along the two dimensions of potentiality/actuality and matter/form as below to lead to a 2×2 matrix of causes.

Niko Tinbergen , a great ethologist, asked four questions or explanations about any biological phenomenon, inspired by the Aristotle’s 4 causes. . From the Wikipedia page:

 

However, I like to arrange it slightly differently. I retain the ultimate/proximate distinction, but supplement it with Accidental/ Teleological distinction. Accidental to me means phylogeny due to random genetic drift and genetic baggage; and physiologic mechanisms like hormones etc kicked in accidentally by random interaction with immediate environment;  on the other hand the process of adaptation and developmental unfolding to an adult form (ontogeny)  appear purposeful and pseudo teleological. Thus my arrangement:

Which leads to how I became re- interested in these four causes recently- it was while reading an article by Dean Simonton on ability , wherein he conjectured that studying both the generic and specific factors that affect performance as well as acquisition of ability is problematic and non-fruitful, that I remembered about these and saw how fruitful it may be to conceptualize ability in just so many terms. Hence my conceptualization:

In general for ability I think the following four factors are applicable and all four have strong influences on ability; I have named them talent, hard work, grit and optimism etc elsewhere. In general for any trait like intelligence, emotionality etc I think the 2×2 factor matrix is relevant and worth keeping in mind.

That brings me eventually to my own levels of explanations for any phenomenon. I believe evo-devo explanations as well as psycho-social factors have equal weight-age while explaining say behavior. while some of these explanations are mechanistic/deterministic other are of non-deterministic or chaotic origin. Similarly, while some are governed by factors internal to the organism others are mostly affected by extrinsic factors.

I hope the above conceptualization makes sense. It is inline with my eight stage model and four domains model where Evo is stage 1&2; social- stage 3&4, devo- stage 5&6 and psycho stage 7&8.

 

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emotion and personality: take 5

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I started the emotion and personality series with a focus on the eight stage model and how that informs us about both personality and emotions. I ended up changing tracks and pursuing Millon’s evolutionary stages and polarities and extending it to the ABCD of four broad psychological domains. Avid readers will notice that both my eight stage model and the Millon’s stages/polarities are based on evolutionary considerations and thus there should be neat synthesis involving the two. this post is an attempt to do so under the framework of the four basic domains of psychology : the ABCD model of psychology.

To recap: all psychology basically can be broken into study of :

  1. Affects or emotions
  2. Behaviors or  social factors
  3. Dynamics or drives and motivations and
  4. Cognition or learning, memory etc.

There have been paradigms in psychology like affective psychology, behaviorism, psychodynamcis and cognitive psychology that have focused on one domain more than the other. One can even extrapolate the diffrent approaches and discplines that are releavnt to each domain as below:

  1. Affect/emotions: Evolutionary explanations as most emotions are evolved mechanisms. Biological context is relevant. Genes drive this.
  2. Behaviors/social functioning: Social/situational explanations dependent on interactions with other people/cultural effects. Cultural context is more relevant. Environment drives this.
  3. Dynamics/ drives/motivations: Developmental explanations of how life course and needs/drives interact. Ecological context is instrumental. Environment chooses genes here and only certain phenotypes expressed.
  4. Cognition: economic/information-processing explanations that explain decisions, perceptions etc. Constructed and created context is important here. Niches are build and genes choose environment.

The Affect and Dynamics can be clubbed together as Evo-devo explanations and refer to subjective phenomenon;  while the Behavior and Cognition can be clubbed together as Socio-Economic explanations and refer to objective observable phenomenons. But anyway this is digressing a bit from the main topic.

Getting back to topic at hand, the four domains correspond to the four evolutionary stages of millon and each stage has two polarities and thus map to eight stage model as follows:

  1. Affect maps to problem of Existence and the polarity of pain and  pleasure mapped respectively to say the  ‘FEAR’ and ‘SEEKING’ system of Pankseep. These (the panksepp emotions systems)  I have previously shown how they are mapped to the eights stage model.
  2. Behavior maps to the problem of Adaptation and the polarity of Active and Passive mapped respectively to the ‘RAGE’ and ‘PANIC’ systems of panksepp.
  3. Dynamics/Drive maps to the problem of Replication and the Polarities of Self and Other mapped respectively to ‘LUST’ and ‘CARE’ of Panksepp.
  4. Cognition maps to the problem of abstraction and the polarities of Broad/creative versus narrow/rigid and maps respectively to ‘PLAY’ and ‘SELF’ systems of Panksepp.

Seen form this angle, the eight stages are just the eight polarities manifesting one after the other in the developmental course.

Extending Millon’s evolutionary considerations,it behooves to remember that another way to look at his problems is to view the change sin phylogeny, ontogeny , function (ultimate) and causation (proximate) of any trait.

Phylogeny is dependent on historical environment and leads to the trait having its ultimate thematic value. This I argue is the problem of existence (of trait/individual) and manifests as the domain of Affect.

But a trait with a fixed value would be of no use. Around the ultimate thematic value there will be ultimate variation that charts the possible functional map of what that feature is supposed to do. The abstracted ancestral environment (EEA) is teh context in which function evolves. This is the problem of abstraction and manifests as domain of cognition,.

Apart form the ultimate thematic value, one needs to tune that value to the immediate ecological and developmental context.  Ontogeny is dependent on such an ecological context and is a proximate thematic mechanism that leads to a particular stable thematic value of a trait. This is also the problem of Replication (r-K)  and manifest as Dynamics.

However, even a fixed proximate thematic value of trait will be useless as situations keep changing. Causation is responding to immediate environment in appropriate and adaptive manner. This is the problem of adaptation and manifests as domain of behavior.

I can relate the above to Aristotle’s four causes, but will leave that for another day; time now to wrap up the personality part. Emotions we have seen can be easily subsumed under the ABCD domains of psychology. As Pankspess model has been related to cloninger personality traits, I’ll leave the case rested that personality can also be adequately explained using the ABCD construct.

Before signing off, I’ll hastily note that to me, these ABCD domains map to underlying neurotransmitter systems:

Affect (pain/pleasure/’FEAR’/'SEEKING”) is associated with Noradrenaline system (NE). the role of ?NE in FEAR is clear, but for SEEKING DA also seems to play a role.

Behavior(active/passive/’RAGE’/'PANIC’)  is associated with Serotonin system (SE). The relationship of Serotonin with aggression and separation distress as well as behavioral manifestations like eating/sleeping cycle are well known. Known abnormalities in SE also cause OCD/Panic attack etc. Known abnormalities lead to fatigue, lethargy etc.

Dynamics (self/other/LUST/CARE)  is associated with Dopamine (DA). Known abnormalities in DA cause motivational obscurity like paranoia/psychosis.

Cognition (creative/rigid/’PLAY’”/SELF) is asscoited with Acetylcholine (ACh) and known abnormalities in ACh here lead to Alzheimer etc.

That shall be all for now.

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Altruism as a result of sexual selection

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There is a new article in BPS, that has found some evidence for the fact that altruism may have evolved by the process of sexual selection.

There are many mechanisms that underlie exactly how and why sexual selection takes place- one is the ‘handicap’ /’costly honest signal‘ theory according to which a trait that is actually disadvantageous or a handicap for the host evolves to signal exactly that fact- that despite this handicap I am able to function well and must therefore be of better genetic quality; the most common example being the evolution of peacocks tail which is a handicap and makes the male peacock carrying a big tail more vulnerable for predation, but also is attractive to females and preferred by them.  Another theory is that of ‘runaway selection’ i.e . a trait may evolve in a direction due to some genetic drift and the preference for it may also evolve in tandem such that there is  a slight leaning or preference towards that trait. Now, in a competition, those, typically males, who have that trait will be selected by the females and their progeny will have an advantage as they are more likely to display that trait and be favored by subsequent generations; thus an arbitrary trait may get fixed by this runaway selection where all members of the species want to be part of the new fashion/club in town. I know I am drawing very loose analogy, but just to give an idea. Nakedness or loss of hairs in humans is predicted to have followed this pattern.

Of course sexual selection also differs on whether it is largely intrasexual, driven by competition (selection pressure) between males for eg  having big antlers to defeat and subjugate another male; or is driven by mate preferences and has intersexual selection dynamics- like the peacocks tail.

What the authors of this paper hypothesized was that sexual selection is behind the evolution of altruism or selfless concern with non-kin and that this being the case and this sexual selection dynamics being driven by inetrsexual dynamics, there are bound to be genetic underpinnings to both the trait altruism as measured in males/females and the mate preferences for altruistic trait in both females as well as males. The reason they didn’t anticipate any differences in male sand females was that parental investment, as per them, is roughly equal in case of humans and so both males and females exert equally strong sexual selection pressure son each others traits and ‘choose’ their mates equally.

However, in this study they looked only at females and their genetic basis for altruistic traits as well as mate preference for altruism. The altruistic traits and mate preferential weer measured using self-report instruments.  the genetic components underlying these were estimated using classical twin studies paradigm where correlation between mono-zygotic twins and di-zygotic twins are compared to estimate the genetic contribution. They also calculated the phenotypic correlation between mate preference for altruism and altruistic trait in individuals and tried to calculate how much of this correlation again was genetic in nature or in other words was a result of  mating between those who had the trait and those who preferred the trait. . They hypothesized that in the ancestral environmental this type of mating for trait altruism would have taken place and thus these would be genetically correlated.

This is exactly what they found; they found that both altruistic personality and mate preference for altruism had genetic components and that they both co-varied and that covariance again had genetic component.  the pare itself is full text open access and is written very well, so go ahead and read it yourself. this is an important paper that has come timely when the whole kin-selection paradigm for evolution of eusociallity is being challenged by E o Wilson and team and provides a fresh and alternative perspective of why altruism may have evolved.

Here is a tit-bit from the discussion:

We believe that the sexual selection hypothesis for the evolution of human altruistic traits should now be considered alongside other more established theory (Bshary & Bergmu¨ller, 2008; Lehmann & Keller, 2006), particularly as there is the possibility that multiple mechanisms might underlie a complex behaviour such as altruism. Empirical testing of contrasting theories might even be possible. For example, reciprocal altruism (Trivers, 1971) does not strictly predict the genetic correlation between MPAT and ‘altruistic personality’ found here as ongoing reciprocation towards others would not necessarily result in such a selective process. Indirect reciprocity (Leimar & Hammerstein, 2001) concerns reputation directed towards all other group members while the sexual selection hypothesis focuses solely on altruistic displays that can be evaluated by potential mates (Phillips et al., 2008). A study that examined ‘costly signalling’ of altruistic behaviour through personal donation to a children’s charity found a significant effect on male behaviour when witnessed by a female observer while no such effect was found when male participants were observed by same sex others (Iredale et al., 2008), a finding that could be seen to be at odds with indirect reciprocity. Additional studies could further elucidate the effects of altruistic reputation when directed towards same sex others as opposed to potential mates, thus testing the relative claims of indirect reciprocity against the sexual selection hypothesis.

Tim Phillips1, Eamonn Ferguson2, & Fruhling Rijsdijk (2010). A link between altruism and sexual selection: Genetic influence on altruistic behaviour and mate preference towards it British Journal of Psychology DOI: 10.1348/000712610X493494

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