T ii 2 5 5 26 27 28 32 41 -6. F Skinner (1981 p. 502) 24 P7001016539000000000000000000A3A]/4[P700101653900000... O QAA P Skinner's discovery and subsequent elucidation of operant selection by consequences have rightly been called "revolutionary" and "the bedrock on which other behavioral principles rest" (Glenn, 2004, p. 134). Selectionism "anchors a new paradigm in the life sciences.... A basic tenet of this position is that all forms of life, from single cells to complex cultures, evolve as a result of selection with respect to function" (Pennypacker, 1994, pp. 12-13). Selection by consequences operates during the lifetime of the individual organism (ontogeny D) and is a conceptual parallel to Darwin's (1872/1958) natural selection in the evolutionary history of a species (phylogeny D). In response to the question "Why do giraffes have long necks?" Baum (2017) provides this excellent description of natural selection: 9To learn more about the role of selectionism in Darwinian evolutionary biology and Skinnerian behaviorism, see Leo, Laurenti, and Haydu (2016 ); Moxley (2004); and Reese (1994). [Return to reference] Darwin's great contribution was to spe that a relatively simple mechanism could help explain why phylogeny followed the particular course it did. The history of giraffes' necks, Darwin saw, is more than a sequence of changes, it is a history of selection. What does the selecting? Not an omnipotent Creator, not Mother Nature, not the giraffes, but a natural, mechanical process: natural selection. Within any population of organisms, individuals vary. They vary partly because of environmental factors (e.g., nutrition), and also because of genetic inheritance. Among the giraffe ancestors that lived in what is now the Serengeti Plain, for instance, variation in genes meant that some had shorter necks and some had longer necks. As the climate gradually changed, however, new, taller types of vegetation became more frequent. The giraffe ancestors that had longer necks, being able to reach higher, got a little more to eat, on the average. As a result, they were a little healthier, resisted disease a little better, evaded predators a little better on the average. Any one individual with a longer neck may have died without offspring, but on the average longer-necked individuals had more offspring, which tended on the average to survive a little better and produce more offspring. As longer necks became frequent, new genetic combinations occurred, with the result that some offspring had still longer necks than those before, and they did still better. As the longer-necked giraffes continued to out-reproduce the shorter-necked ones, the population consisted more and more of longer-necked individuals, and the average neck length of the whole population grew. 16539000000000000000007204.xhtml#P7001016539000000000000000007700 47F Light rain < 33 /890 4) 7:34 PM and some had longer necks. QAA P As the climate gradually changed, however, new, taller types of vegetation became more frequent. The giraffe ancestors that had longer necks, being able to reach higher, got a little more to eat, on the average. As a result, they were a little healthier, resisted disease a little better, evaded predators a little better -on the average. Any one individual with a longer neck may have died without offspring, but on the average longer-necked individuals had more offspring. which tended on the average to survive a little better and produce more offspring. As longer necks became frequent, new genetic combinations occurred, with the result that some offspring had still longer necks than those before, and they did still better. As the longer-necked giraffes continued to out-reproduce the shorter-necked ones, the population consisted more and more of longer-necked individuals, and the average neck length of the whole population grew. (pp. 59-60) Just as natural selection requires a population of individual organisms with varied physical features (e.g., giraffes with necks of different lengths), operant selection by consequences requires variation in behavior. Those behaviors that produce the most favorable outcomes are selected and "survive," which leads to a more adaptive repertoire. Natural selection has endowed humans with an initial population of uncommitted behavior (e.g., babies babbling and moving their limbs about) that is highly malleable and susceptible to the influence of the consequences that follow it. As Glenn (2004) noted, By outfitting humans with a largely uncommitted behavioral repertoire, natural selection gave our species a long leash for local behavioral adaptations. But susceptibility of human behavior to operant selection. Although this behavioral the uncommitted repertoire of humans would be lethal without the characteristic is shared by many species, humans appear to be most exquisitely sensitive to behavioral contingencies of selection (Schwartz, 1974). (p. 139) Operant Conditioning Operant conditioning may be seen everywhere in the multifarious activities of human beings from birth until death.....It is present in our most delicate discriminations and our subtlest skills; in our earliest crude habits and the highest refinements of creative thought.