0:00
This
lecture is about the connections
between developmental
plasticity, evolution,
and the origins of disease.
My name is Mary Jane West-Eberhard,
and I work for the Smithsonian
Tropical Research
Institute in Panama,
while living most of
the time in Costa Rica.
I confess that I am not
a medical researcher.
I am an evolutionary biologist.
My research is primarily field work
on the natural history and behavior
of tropical social wasps.
0:24
Observations on these exquisitely
conditioned sensitive organisms
led first to an interest in the
origin of workers and queens.
0:32
Which of these two forms, as
developed by an individual female,
is environmentally determined?
From studying these, I got
interested in developmental
plasticity in general.
0:44
Developmental plasticity is
simply the responsiveness
of the phenotype to new
inputs from the external
or the internal environment.
It's phenotypic change
without genetic change.
0:56
The word phenotype, of course,
refers to all traits of an organism
other than its genes.
This includes molecular
products of genes,
morphology, physiology, and
behavior, including learned traits.
It includes nervous tics,
remembered phone numbers, and spots
on the lung following
a bout with the flu.
That is, phenotypes can be
adaptive or pathological,
permanent or temporary, and
typical or atypical of a species.
1:23
Developmental
plasticity is a broader
concept than phenotypic plasticity.
Phenotypic plasticity
is responsiveness
to the external environment.
Developmental plasticity
includes responses
to the internal environment.
This means that includes
sensitivity to things
like gene products within cells and
the action of hormones on tissues.
Developmental plasticity
includes modularity of structure.
