What was Darwin’s dilemma? We know he was concerned that marrying his cousin could result in health problems for his offspring. A keen pigeon fancier, he was sharply aware of the concept of hybrid vigour and the dangers of inbreeding. Yet he was in love. This dilemma he resolved by following his heart.
Kirschner and Gerhardt would remind us that Darwin’s dilemmas extended beyond the realm of the familial and one in particular remains unresolved to this day.
To whit, how does variation occur?
The modern synthesis holds that random genetic mutation provides variation. This variation is acted upon by selection pressures. Thus does the organism become adapted to survive and thrive in the environment where the selection pressures are active. Genes pass on these adaptive genes to offspring, whereby a population of organisms with a higher frequency of an adaptive gene will arise.
Yet mutation alone does not occur at a rate sufficient for evolution. What other processes are at work that confer adaptibility?
Perhaps it is that the facility for variation has itself evolved. Genomes can therefore be said to have plasticity. Organisms have a tendency to produce potentially advantageous variations with every generation. Random mutation is a part, plasticity makes a whole.
The authors call their resolution of Darwin’s dilemma ‘facilitated variation’. To quote:
“Organisms are not analogous to human-engineered machines (contrary to what creationists and proponents of intelligent design keep insisting); rather, they are characterized by developmental systems that are capable of accommodating quite a bit of disruption—be that from changes in the external environment (phenotypic plasticity) or from mutations in their genetic makeup (genetic homeostasis). This ability to accommodate is in turn made possible by the modular structure of the genetic-developmental system itself, which allows organisms to evolve new phenotypes by rearranging existing components. ”
Is it possible that the question of variation has been resolved? Read for yourself and decide.
What happens when an actor teaches charismatically and non substantively on a subject about which he knows nothing?
If he is a really good actor, and his performance is sufficiently plausible, and…
“…Given a sufficiently impressive lecture paradigm, even experienced educators participating in a new learning experience can be seduced into feeling satisfied that they have learned despite irrelevant, conflicting, and meaningless content conveyed by the lecturer.
The hypothesis was supported when 55 subjects responded favorably at the significant level to an eight-item questionnaire concerning their attitudes toward the lecture.
The study serves as an example to educators that their effectiveness must be evaluated beyond the satisfaction with which students view them. The authors conclude by emphasizing that student satisfaction with learning may represent little more than the illusion of having learned.”
His large erection may have resulted from accidentally (?) merging his navel with his penis during a Victorian re-cut of the figure.
Also plausible: that the figure represents Oliver Cromwell.
Not likely but apparently true: that a huge chalk figure of a naked and very priapic guy should appear on a hillside outside of one’s town, and nobody has a clue who did it.
Rest assured however, the Institute for ExtraSpatial Studies has deemed these eventualities to be implausible in the extreme.
Class I: Plausible within 100 years
Class II: Plausible within 1000 years
Class III: Implausible on any timescale