darwin so I'm sure we all heard of
Darwin um you know he wrote that book
the Origin of Species back in eighteen
1850s and you know he really came up
with a theory of natural selection and
evolution and kind of what led him to
this theory was that he had a voyage on
the HMS Beagle and this voyage you know
at the time actually he was very lucky
actually got to circumnavigate the globe
and you know he got to study a lot of
different you know biological systems
and those kind of things but one of the
main things that he actually gathered
from that was the Galapagos Island
finches and these birds he noticed they
they varied in their beak size so for
instance you know he would find a bird
that had like a beat kind of like you
know like sharper and longer and these
were you know mainly for eating cacti
and then he would find you know another
bird on a you know the same island or a
different Island would would have you
know kind of a beak like this you know
more4 for eating insects you know and
flies in these kind of things and and
then he'd find birds with these big
hunker in beaks you know that were they
found you know nibbled on on seeds and
those kind of things so he would see
that you know well wow they're all these
different types of birds yet they all
have these different adaptations you
know to their environment to their food
and you know the food accessibility that
have in each environment and so um you
know Darwin he observed several things
on for selection wise and one of those
things was that you know all the traits
are irritable meaning that you know
traits are passed down from from parent
to offspring the other important you
know observation is that not all the
offspring survive this means that you
know a habitat may not have enough
resources to support all the offspring
and you know going co in hand with that
is that individuals breed of high rates
and if these individuals are breeding is
such a high rate you know the the
environment just can't
support that many offspring and the
fourth observation they has is that you
know individuals vary in the trance
meaning that you know all individuals
they differ in some way or another from
each other and what he kind of inferred
from these these four observations that
he had was that you know the individuals
that had more favorable traits for their
environment tended to reproduce and
survive at higher rates than those that
did not have the favorable traits and
these favorable traits tended to
accumulate over over generations and
over periods of time oh yes and also
another very important thing to get off
natural selection is that the individual
himself or herself does not actually
evolve is actually the population that
evolves so when we're talking about
natural selection we're talking that it
you know we're talking about you know
individuals not evolving but the actual
population of it evolving so for
instance say we have you know a group of
I don't know like black black insects
you know black and grey insects and
these black insects um you know say say
there was like say there's like four of
them here and these guys are all these
guys are all black and then then we had
um we had like one white one there but
then slowly over time over time
the black ones tended to not survive for
I don't know what reason but as you can
see the individual himself is not is not
actually evolving it's the whole
population that's evolving 22 towards
the the trend of white beetles
