Natural Selection (The Basics)
•Certain species have traits that
improve survival in a given
environment (Those traits will get
passed on to their offspring).
•Those species who do not have the
trait eventually die off.
•Basically, the species that is best
suited to their environment live and
reproduce, those that can’t do not
make it (survival of the fittest).
The essential elements of Natural Selection can be
remembered by using the acronym V.I.S.T.
V = Variation: All life forms vary
genetically within a population. It
is this genetic variation upon
which selection works.
I = Inheritance: Genetic traits
are inherited from parents and are
passed on to offspring.
S = Selection: Organisms with
traits that are favourable to their
survival get to live and pass on
their genes to the next generation.
These traits develop in a Examples
population through adaptation
(change colour, produce toxins Galapagos Finches
etc).
T = Time: Evolution takes time. The Candy Bowl
Evolution can happen in a few
generations, but major change,
such as speciation, often takes
long periods of time.
Genetic Proof of Evolution
• Darwin did not know how characteristics were
inherited.
• This was solved by an Austrian monk named
Gregor Mendel (1822 – 1884).
• He provided this by cross-breeding pea plants.
• He proved that genetic material is passed on
from parent to offspring by normal sexual
reproduction or small mutations (this is the
backbone of Natural Selection).
Human Proof of Evolution
• Evolution is a bush, not a ladder.
• Human evidence is provided through studying
other forms of plant / animal evolution.
• Finding intermediary species, like
fossilized remains of “hominids”.
Example
“Lucy”
Evolution
of
the
Whale
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Australopithecus Afarenis (Lucy)
• Named after a Beatles
song
• 3 – 4 million years
old.
• Found by Donald
Johanson
• Believed, until
recently, to be the
missing link.
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Intermediary Species
Part fish, Part animal – (transitional animal)
Found on Ellesmere Island in Canada’s arctic Back