Transcript FIT C Ch3 evolution

BEHAVIOR WITHOUT LEARNING
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection
Addendum: 3A. Phylogeny, Ontogeny and Behavior
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection
Evolution is a name for something that happens. It is
not a theory.
Darwin’s account is a theory about why evolution
happens.
Some history: Other theories of evolution and the
eclipse of Darwinism:
Lamarckism
Orthogenesis
Mendelian genetics
The Modern Synthesis: Mendelian genetics,
Darwinian selection, and mutation research
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection; Sexual Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection
• Variability and selection go hand in
hand -- you cannot have one without
the other
• Once variability is created, change
(evolution) follows
• Selection, whether in phylogeny or
in ontogeny or in cultural practices,
will happen
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity: e.g., the eye
Evolution and Development
Kinds of Selection
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development: Evo-Devo
Kinds of Selection
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development: Evo-Devo
Modules, Boundaries, and Genetic Switches
Kinds of Selection
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development: Evo-Devo
Modules, Boundaries, and Genetic Switches
Epigenetics
Kinds of Selection
Evolution and Development
Chaos Theory and Darwin’s Butterfly
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection
Three Varieties of Selection
Natural or Phylogenic Selection
Selection by the environment of populations of
organisms (and therefore populations of genes)
Operant or Ontogenic Selection
Selection of behavior by its consequences within
the lifetime of the individual organism
Cultural or Memetic Selection
Selection of behavior as it is passed on from one
organism to another
Three Varieties of Selection
- Phylogenic (Darwinian selection)
- Ontogenic (operant selection)
- Cultural (memetic selection)
• The three varieties may work in concert or in
opposition to one another (consider drugs as
reinforcers in ontogeny, but with deleterious
effects at the other levels of selection).
• Scenarios about human origins (including the
evolution of verbal behavior) must take all three
levels into account.
Selection for Variation
in Behavioral and Biological Systems
• We will see later that variability itself can be selected. There
are advantages to variability: for example, coming up with
effective new responses in unusual environments
• A parallel in biology is that species otherwise seeming similar
in phenotype can vary in their genetic diversity, and those
with the greater genetic diversity have selective advantages
over the others, especially in the face of changing
environments. A substantial research literature supports this
conclusion.
What are the implications?
• A wider range of variations makes a
population more viable under changing
contingencies. Species at risk are especially
those in very specialized environments.
• These populations may exist at any level of
selection: phylogeny, ontogeny, or culture
(though selection at one level need not
support selection at another).
• Species, behavior patterns and cultures that
include many variations may have advantages
over those that are less flexible.
Historical Challenges
• Variations are essential to selection
• Darwinian thinking went through an eclipse
• The source of novelty was the issue: Mendelian
genetics couldn’t provide it.
• Mutation research made the difference.
• There was a parallel challenge, especially from
linguistics, to behavioral thinking, which is now
emerging from its eclipse.
• In that case too, sources of novelty were the issue:
How can children say novel things they’ve never
heard before?
Evolution and Development
The Nature of Evolution
Recipes and Blueprints
Variation and Selection
The Origins of Complexity
Evolution and Development
Kinds of Selection