A&O – EVOLUTION of ART

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EVOLUTION by means of NATURAL SELECTION

key observations and their inferences

• Overproduction [individuals tend to produce as many offspring as possible]
• Stability [population size seems to remain stable from generation to generation in stable environments]
• Limited resources [there is not enough for everyone]
• COMPETITION: Struggle for existence inferred
• Variability [offspring manifest varying traits]
• Heritability [traits are to some extent inherited]
• DIFFERENTIAL SURVIVAL (=Natural selection) inferred [some traits allow their bearers to produce more offspring than other individuals = be more fit]
• EVOLUTION: Over many generations, differential survival leads to changes in the frequencies of genes and thus the traits they influence.

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KEY TERMS

ADAPTATION. “The processes by which organisms or groups of organisms maintain homeostasis in and among themselves in the face of both short-term environmental fluctuations and long-term changes in the composition and structure of their environments.”  (Rappaport, 1971). https://neilgreenberg.com/ao-evolution-adaptation-07-18-2017/

SEXUAL SELECTION.  “Sexual selection is a “special case” of natural selection. Sexual selection acts on an organism’s ability to obtain (often by any means necessary!) or successfully copulate with a mate” (Evolution 101, Berkeley)

SELECTION PRESSURE can be exerted by any elements of the developmental environment with which an organism must cope to fully express its latent potential in a way that enhances FITNESS. It can affect the organism at any stage in development.

FITNESS.  The extent to which an individual contributes to subsequent generations is is manifested through its phenotype—the corporeal, manifest expression of gene activity.  It is profoundly affected by the environment at all stages of development—that is, “the fitness of a given phenotype can also be different in different selective environments.”     (Wikipedia on Fitness).  DIRECT FITNESS (effects on direct kin) and INDIRECT FITNESS (effects on with whomever you share any proportions of genes) (together terned “INCLUSIVE”)

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