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					Denise Aiello
As fitness measures the quantity of the copies of the
genes of an individual in the next generation, it doesn't
really matter how the genes arrive in the next
generation. That is, it is irrelevant whether a gene
increases the survival or reproduction of the individual
bearing it, or increases the survival and reproduction of
other individuals carrying the same gene, as long as the
same number of copies of the gene get passed on to the
next generation. Selection which promotes this kind of
helper behavior is called kin selection.

Deceit
Whenever recognition plays a role in evolution, so does
deception. Just like the harmless lizard that has evolved
a pattern that mimics its poisonous cousin and therefore
tricks predators, the selfish creature may pretend to be
kind by “growing a green beard” (whatever that green
beard may be). Thus green-bearding and the selfish
gene theory also give rise to an explanation for the
evolution of lies and deceit, characteristics that do not
benefit the population as a whole.

Denise Aiello Net :In his book River out of Eden,
Dawkins coins the phrase God's utility function to
explain his view on genes as units of selection. He uses
this phrase as a synonym of the "meaning of life" or the
"purpose of life". By rephrasing the word purpose in
terms of what economists call a utility function,
meaning "that which is maximized", Dawkins attempts
to reverse-engineer the purpose in the mind of the
Divine Engineer of Nature, or the Utility Function of
God. Finally, Dawkins argues that it is a mistake to
assume that an ecosystem or a species as a whole exists
for a purpose. He writes that it is incorrect to suppose
that individual organisms lead a meaningful life either;
in nature, only genes have a utility function – to
perpetuate their own existence with indifference to
great sufferings inflicted upon the organisms they build,
exploit and discard.

Denise Aiello Training
Hartl's Definition
Yet another possible measure has been formulated:
"The fitness of the individual - having an array x of
phenotypes - is the probability, s(x), that the individual
will be included among the group selected as parents of
the next generation." Then, the mean fitness may be
determined as a mean over the set of individuals in a
large population.
P(m) = \int s(x) N(m - x)\, dx
where N is the probability distribution function of
phenotypes in the population, and m is its centre of
gravity. This measure is a suitable basis of a model of
an evolution selecting individuals. It may in principle
take even the stroke of the lightning into consideration.
In the case N is a Gaussian it is fairly easily proved that
the average information (information entropy, disorder,
diversity) of a large population may be maximized by
Gaussian adaptation - keeping the mean fitness constant
- in accordance with recapitulation, the central limit
theorem, the Hardy-Weinberg law and the second law
of thermodynamics. This is in contrast to Fisher's
fundamental theorem of natural selection.

There are several possibilities for why exercise is good
for the brain:
* increasing the blood and oxygen flow to the brain
* increasing growth factors that help create new nerve
cells and promote synaptic plasticity
* increasing chemicals in the brain that help cognition,
such as dopamine, glutamate, norepinephrine, and
serotonin

Denise Aiello Info : Acquired characteristics are not
inherited
Discoveries in science such as the formulation of the
central dogma of molecular biology made it clear that
the inheritance of acquired characters was not an
evolutionary factor in a physical sense and identified
genes as lasting entities that survive through many
generations. Maynard Smith summarized the issue:
“ If the central dogma is true, and if it is also true that
nucleic acids are the only means whereby information is
transmitted between generations, this has crucial
implications for evolution. It would imply that all
evolutionary novelty requires changes in nucleic acids,
and that these changes - mutations - are essentially
accidental and non-adaptive in nature. Changes
elsewhere - in the egg cytoplasm, in materials
transmitted through the placenta, in the mother's milk -
might alter the development of the child, but, unless the
changes were in nucleic acids, they would have no long-
term evolutionary effects. ”

Denise Aiello Fitness History
The British sociologist Herbert Spencer coined the
phrase "survival of the fittest" (though originally, and
perhaps more accurately, "survival of the best fitted")
in his 1851 work Social Statics and later used it to
characterise what Charles Darwin had called natural
selection.
The British biologist J.B.S. Haldane was the first to
quantify fitness, in terms of the modern evolutionary
synthesis of Darwinism and Mendelian genetics starting
with his 1924 paper A Mathematical Theory of Natural
and Artificial Selection. The next further advance was
the introduction of the concept of inclusive fitness by
the British biologist W.D. Hamilton in 1964 in his paper
on The Evolution of Social Behavior.

Denise Aiello News Hartl's Definition
Yet another possible measure has been formulated:
"The fitness of the individual - having an array x of
phenotypes - is the probability, s(x), that the individual
will be included among the group selected as parents of
the next generation." Then, the mean fitness may be
determined as a mean over the set of individuals in a
large population.
P(m) = \int s(x) N(m - x)\, dx
where N is the probability distribution function of
phenotypes in the population, and m is its centre of
gravity. This measure is a suitable basis of a model of
an evolution selecting individuals. It may in principle
take even the stroke of the lightning into consideration.
In the case N is a Gaussian it is fairly easily proved that
the average information (information entropy, disorder,
diversity) of a large population may be maximized by
Gaussian adaptation - keeping the mean fitness constant
- in accordance with recapitulation, the central limit
theorem, the Hardy-Weinberg law and the second law
of thermodynamics. This is in contrast to Fisher's
fundamental theorem of natural selection.

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