SOCIOBIOLOGY LECTURE 1
Sorry this email is so long in the pipeline, but i am still a
little confused as to some of the concepts we discussed on
Tuesday. I've started to read some of the 'blind watchmaker'
and felt like we touched on some of the core principles in
the seminar, on what Dawkins is going on about. Therefore,
this email is about them - even though i'm probably way 'off
the mark'
Sociobiology looks at the variation across species of
particular physical and behavioral characteristics. That is,
why a species today looks and acts the way it does when
compared to another species. Behavioral Genetics, on the
other hand, looks at the variation of certain physical and
behavioural characteristics within the population of that
species. For example, sociobiology would look at why all
members of the human species - with a few exceptions - have
the ability to run standing up. Behavioral genetics would
look at why it is some individual humans within this species
can run faster than others, and whether this is due to
genetic factors or to the influence of the environment the
individual existed in (i.e. did the individual train a great
deal)
In order to explain the existence of these physical and
behavioral characteristics in species, sociobiology looks to
the evolutionary history of that species for answers. In
essence, those physical and behavioural characteristics which
best helped individuals in the past survive and reproduce,
were passed onto the next generation of the species. Those
characteristics which did not help the individual survive in
that environment were not passed on, as that characteristic
was lost in the death of that individual.
Questions - 1) How then are these characteristics in
individuals passed onto the next generation and 2) how do we
get species with different characteristics? Plus, 3) how does
the past environment allow for one characteristic to be passed
on, but not another?
To answer this, three elements have to be identified - (this
is where I got a little confused, but I^Òll have a stab at it
anyway)- a species Genotype (GT), a species Phenotype (PT)
and the Environment of Evolutionary Adaption (EEA).
A species GT are kind of like instruction manuals, and
species PT are kind of like houses that these instruction
manuals sit in. The instruction manual is a manual for
building an exact copy of itself and the house. In a-sexual
reproduction the individual has a whole instruction manual,
and so can build a copy of itself any time it so wishes.
However, in most species (humans included)an individual only
has half the instruction manual and so needs to mate with
another member of its own species - who has the other half of
instructions (i.e. a member of the opposite sex) - in order
to make a copy of itself. However, this ^Ñoffspring
instruction manual and house^Ò is not an exact copy of its
parents, but an amalgamation of two instruction manuals as
well as any mishaps/ mutations that may have occurred when
the instruction manuals came together.
What happens now, is that if this new ^Ñoffspring instruction
manual and house^Ò has been given a house that aids it in
finding another instruction manual or helps it exist in its
environment, then, when it copies itself with another manual
it passes this mutant characteristic into the next offspring.
The EEA, is this past environment in which certain mutant
characteristics were chosen over others. The choice of which
characteristic is successful and passed on is not in the
control of the instruction manual or the house, nor is it in
the hands of the environment - as that is continually
changing - but it is the hands of chance, because only chance
decides which instruction manual and house ^Ñfits
successfully^Ò into which environment.
Over time, houses have become extremely complicated physical
structures with sets of behaviours, and so have the
instruction manuals needed to create them.
Answers - 1) Complex characteristics in individuals and
species today, are transferred to the next generation by the
reproducing instruction manuals. 2)Variations of these
complex characteristics in a population of a species occur
because of the amalgamation of the two halves of instruction
manual needed to make a copy, as well as any mutations that
occur during the reproduction process itself. 3) The past
environment allows for one characteristic to be passed on and
not another, but only when that characteristic fits that
particular environment. However, the population of a species
have no control as to whether their particular variant
characteristic will be successful in that environment, and
neither does the environment - the whole process is done by
blind chance
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