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Tinbergen 1963
Alcock’s paraphrase of Tinbergen
• How does the behavior promote an animal’s
ability to survive and reproduce?
• How does an animal use its sensory and motor
abilities to activate and modify its behavior
patterns?
• How does an animal’s behavior change during
its growth, especially in response to the
experiences that it has while maturing?
• How does an animal’s behavior compare with
those of other closely related species, and what
does this tell us about the origins of its behavior
and the changes that have occurred during the
history of the species?
Figure 1.1 The monogamous prairie vole
Figure 1.2 The brain of the prairie vole is a complex, highly organized machine
Figure 1.3 A gene that affects male pairing behavior in the prairie vole
Figure 1.7 Testing the hypothesis that male monogamy is influenced by a single gene
Figure 1.4 The evolutionary relationships of the prairie vole and six of its relatives
Box 1.1 How are phylogenetic trees constructed and what do they mean?
Conroy and Cook 2000
Figure 1.5 The possible history behind monogamy in the prairie vole
Figure 1.11 Artificial selection causes evolutionary change as predicted by the theory of natural
selection
Figure 1.12 A test of whether dogs are more sensitive to signals from human beings than are
hand-reared wolves
Figure 1.13 Hanuman langur females and offspring
Figure 1.14 Male langurs commit infanticide
Figure 1.15 Variation in suicidal tendencies in a make-believe lemming-like species
Adaptation
An adaptation is, thus, a feature of
the organism, which interacts
operationally with some factor of its
environment so that the individual
survives and reproduces.
(Bock, 1979, p. 39)
Adaptation
"The ground rule -- or perhaps doctrine would be a better
term -- is that adaptation is a special and onerous concept
that should be used only where it is really necessary . . . A
frequent practice is to recognize adaptation in any
recognizable benefit arising from the activities of an
organism. I believe that this is an insufficient basis for
postulating adaptation and that is has led to some serious
errors. A benefit can be the result of chance instead of
design. The decision as to the purpose of a mechanism must
be based on an examination of the machinery and an
argument as to the appropriateness of the means to the end.
It cannot be based on value judgments of actual or probable
consequences."
(Williams, 1966)
Adaptation
"The sutures in the skulls of young mammals
have been advanced as a beautiful adaptation
for aiding parturition, and no doubt they
facilitate, or may be indispensable for this act;
but as sutures occur in the skulls of young birds
and reptiles, which have only to escape from a
broken egg, we may infer that this structure has
arisen from the laws of growth, and has been
taken advantage of in the parturition of the
higher animals."
(Darwin, 1859, p. 197)
Adaptation
"If whole populations are adaptive, it seems
possible that adaptations producing beneficial
death of an individual -- death for the benefit of
the population might evolve . . . It may be
concluded from these data that . . . natural
selection operates upon the whole interspecies
system, resulting in the slow evolution of
adaptive integration and balance. Division of
labor, integration, and homeostasis characterize
the organism and the supraorganismic
interspecies population. The interspecies system
has also evolved these characteristics of the
organism and may thus be called an ecological
supraorganism." (Allee et al., 1949)
Adaptation
Benefits to groups can arise as statistical
summations of the effects of individual
adaptations. When a deer successfully
escapes from a bear by running away, we
can attribute is success to a long ancestral
period of selection for fleetness. Its fleetness
is responsible for its having a low probability
of death from bear attack. The same factor
repeated again and again in the herd means
not only that it is a herd of fleet deer, but also
that it is a fleet herd.
(Williams, 1966)
Adaptation
Let us now consider the individualistic claim that “virtually all adaptations
evolve by individual selection.” If by individual selection we mean withingroup selection, we are saying that A-types virtually never evolve in
nature, that we should observe only S-types. This is a meaningful
statement, because it identifies a set of traits that conceivably could
evolve, but does not, because between-group selection is invariably weak
compared to within-group selection. Let us call this valid individualism. . .
. If by individual selection we mean the fitness of individuals averaged
across all groups, we have said nothing at all. Since this definition
includes both within- and between-group selection, it makes ‘individual
selection’ synonymous with ‘whatever evolves’ including either S- or Atypes. It does not identify any set of traits that conceivably could evolve
but does not. Let us therefore call it cheap individualism.
(D.S. Wilson, 1989)