Tag: evolutionary theory

Consciousness and Uncertainty Schematization

Mark DavisLeave a comment

If consciousness is an evolved function, the immediate question is what exactly is the currency of evolutionary selection in terms of traits and functions? In almost all of these kinds of arguments there is an explicit requirement that there is on average (or slightly greater than on average) value to survival that results in the maintenance and promotion of the relevant functions. In my Berggruen essay, I argued for a primarily social role to consciousness. Consciousness is a central monitoring framework for the complex web of social interactions that creates a reflective model of a person (and partially and uniquely in certain other species) that can be used to evaluate and plan for sexual pairing and other life choices related to status within social hierarchies. There are other hypotheses, as well, like the idea that predator-prey planning and avoidance is enhanced by a central consciousness experience, including some intriguing work on dreaming (when there is no active consciousness) that shows enhanced dreams for game players who are in the role of being prey within the game context as well as other forms of cognitive activation.

Abstractly, evolution is a distributed adaptation and learning algorithm that is the only robust solution to the complexity of natural environments. Wasteful though it may be, it is the invisible hand that drives forward enhanced prediction and survival using the knobs of genetics and the social relationships that are an extended phenotype in social species. There are a few theories of abstract learning that can be brought to bear on this topic, with the obvious candidate being inductive optimality via Kolmogorov complexity: minimize the model parameters to bottleneck against overtraining and avoid overfitting. This is central to all distributed learning but has layered complexity when considering the how to predict larger, more distal patterns, both temporal and spatial in activation and extent.… Read the rest

Nesting and Spring-loaded Parasitism

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While enjoying your eggs, you should consider what primitive social insects do with theirs. Why? Because it may be essential to our understanding of social behavior and, hence, the notion of moral and ethical behavior. I’m reading Nowak, Tarnita, and E.O. Wilson’s 2010 article (and 43 pages of supporting materials), “The evolution of eusociality” from Nature (466/doi:10.1038/nature09205).

This is a contentious paper, I should add, because it postulates “multilevel selection” that operate at the group or species level. It is remarkable in several ways. First, it uses mathematical terminology to explain aspects if the theory of eusociality (literally: “good sociality” but, theoretically, the highest levels of social interaction) that we rarely see in papers on evolutionary theory. Specifically, ideas like “global updating” are introduced to explain why traditional methods of explaining eusociality are plagued by false assumptions about the spatial distribution of mating opportunities. I’m reminded of my own critique of the microevolution versus macroevolution distinction that pervades anti-evolution arguments: why would nature (or God for that matter) prevent hybridization of species while making it easy for genetic drift within a species? We either have a failure of imagination, the deliberate introduction of barriers to hybridization just to fool all of us or maintain a prescribed order, or we have a continuous transition from micro to macro effects (hint: there is actually no real distinction).

But back to eggs. E.O. Wilson and colleagues suggest that the earliest forms of sociality were among the parasitic wasps, like the Tarantula Hawk. Accumulate prey, stuff eggs into them, and then move on. Next, icky stuff happens in the prey. One allele change can turn the move on behavior off when the local environment is sufficiently rich, however, and then moms and offspring hang around in colonies together.… Read the rest

Multilevel Selection and Proximate Causation

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A strong critique of On the Role of Males by Dawkins was, put simply, that it continues the wrongheaded pursuit of the notion of “multilevel selection” that confuses the vehicles and replicators in the selection process. In this case, selfish genetics precludes the application of a lossy filter for genetic defects because it becomes a species-level selective mechanism.

While largely a technical distinction in evolutionary theory, much remains to be explained if we presume that there are no selective pressures that operate at levels above the genetic. For instance, when human females are subject to environmental stressors, the sex ratio changes to favor boys.  From Valerie Grant’s Wartime sex ratios: Stress, male vulnerability and the interpretation of atypical sex ratio data:

At the end of war, and other times of both chronic and acute stress, remarkable changes occur in the human secondary (birth) sex ratio. At the end of a long war, significantly more boys are born; after a short war, or disaster, fewer boys than usual are born six to nine months later. Since it is commonly held that the sex of the offspring is a matter of chance, these data provide an intriguing problem; but new findings in reproductive physiology, and an increased understanding of male vulnerability, could help resolve it. It appears the sex ratio of offspring may be influenced by variations in the mother’s follicular testosterone. Under conditions of chronic stress, maternal testosterone rises, resulting in an increase in male conceptions; but these same stressful conditions also exacerbate differential male vulnerability, so more males are lost during pregnancy. At the end of war, improving conditions temper male vulnerability, leaving higher sex ratios at birth.

… Read the rest