Download Evolution 1314 - Cobb Learning

Evolution…Whatz Up Wit Dat?

Evolution is change. Galaxies, languages, and
political systems all evolve.

Biological evolution- change in the properties of
populations of organisms that transcend (are
bigger than) the lifetime of a single individual.

Individual organisms do not evolve…they can
change…that’s different. Species evolve.
Applying Natural Selection
1.
2.
Discuss the relationship among genetics,
natural selection, and evolution.
Construct a scenario wherein a
population of organisms (any type you
want) is acted upon by natural selection.
Be sure to discuss all four mechanisms.
Yeah…I know it’s hard; you’re gonna
have to actually think.
Evolutionary Changes are…changes in
populations that are inheritable through
passing of genetic material from one
generation to the next.
 Can be minor or BIG.
 Everything from slight changes in the
amounts of different alleles within a
population, all the way up to…
 …changes that led from the earliest life
forms to worms, fish, lions, and tulips.

Evolution is simply species changing.
 Sometimes its gradual (GRADUALISM).
 Sometimes its fast (PUNCTUATED
EQUILIBRIUM).
 It is always GENETIC!
 The mechanism of evolution is natural
selection (cause and effect...right?).
Natural selection causes species to evolve
(just like tectonic activity causes
continental drift).

Who Is This Darwin Dude?
Well, he was a naturalist who made some
cool observations (remember those) in 1831
while visiting the Galapagos Islands (off the
western coast of South America…Ecuador
to be specific).
 He saw that certain flora (plants) and fauna
(animals) in the islands were slightly
different than those on the mainland.
 Examples: Finch beaks, Tortoise shell
shapes,

He hypothesized that geographic
separation had prompted these critters
to change over time as a response to
the environment in which they lived.
 How? Well…Natural Selection…which
we’ve discussed (Overproduction,
Variation, Competition, & Selection).
 He didn’t know about
genetics…Mendel took care of that
piece of information in the 1840’s.
 We now have modern evolution.

Darwin…did he act alone?
Well…he did but there was another
dude acting alone at the same
time…Alfred Russel (don’t call me
Russell) Wallace.
 Wallace was an admirer of Darwin and
texted him to say that he figured out
the whole natural selection thing.
 And then Darwin was all like…oh no
you didn’t 
 Yes…he did!

More Darwin Stuff
So anywaze…Darwin and Wallace
presented their findings on the same day
at the same meeting.
 Darwin wrote a book though (1859): On
the Origin of the Species by Means of
Natural Selection…so he got the cred.
