Transcript No Slide Title - Hightower Trail

Evolution
Several Species
of Small Furry Animals
Pop Goes
The Weasel: Weasel
Flavored
#9
Gathered Together in a Cave
Popcorn
Are yu smartir
Then a fiffthhh
grayder?
I’m knot.
Gratuitous Beatle
Reference
and Grooving with a Pict.
Gratuitious Pink Floyd
Reference
100
100
100
100
100
200
200
200
200
200
300
300
300
300
300
400
400
400
400
400
500
500
500
500
500
Stuff you
Step in
That tastes
Like chicken
What did Darwin
observe about
finches in the
Galapagos
Islands?
They had different beaks depending
upon where they lived and what they
ate.
Define evolution.
Evolution is the gradual change of a
species over time.
Is a mule a species?
Splain
Nope…nah…no way…nuhh uhh.
A mule isn’t fertile. Members of a
species by definition must be able to
mate and have fertile offspring. That
means their babies have to be able to
have babies. Mules can’t do that.
Sorry mules
What do genes have to do with
evolution?
Only genetically inheritable traits are
impacted by natural selection thus
they are also involved in the process
of evolution.
Explain how a new species can arise
from geographic isolation?
Geographic isolation can separate a group of
individuals from the rest of the species. If the
environment is different enough in the their new
home range, the traits that are helpful to survival will
be different than they were in the old location.
So…these “new” traits will accumulate and
eventually the group may be different enough so that
they can no longer breed with the other group and
produce fertile offspring…ipso facto…new species
This is called allopatric speciation…in case you’re
interested. Actually it’s called that even if you’re
not interested.
You move to Colorado to train for the
Olympics. Training at high altitude develops
your heart muscle, and…You make it!
Congrats! So, you meet and get married to
another athlete who’s trained to develop
awesome super blood pumping capacity. You
two have a kid, soooo goodbye fun and
freedom. Hellloooo diapers full-o-poop and
whining
Here’s the question: does your kid have super
well-developed lung capacity? Explain.
Nope. Sorry.
Why? Well…you trained to develop
your heart…that’s not an inheritable
trait. That lazy little rugrat is gonna
have to get outa da crib and work out
if it wants to have a big ole athletic
heart muscle.
Choose an organism and a habit.
Use the four mechanisms of
natural selection to explain why
these organisms don’t
overpopulate their environment.
Butterfly Fish/Coral Reef
Overproduction: more fish are born than can survive
Variation: there are slight differences among the
individuals…some differences are beneficial to
survival.
Competition: The fish compete for resources (food,
space, mates)
Selection: Better adapted individuals survive and
those traits that help them out are passed on to their
offspring. These beneficial traits accumulate.
Not all of the individuals can compete
and this keeps the population in check.
What are five types/pieces of
information that biologists use to
determine the evolutionary
relationships among organisms?
-Fossils
-Body structure
-Early development morphology
-DNA
-Proteins
What is the difference between
punctuated equilibria and
gradualism?
Punctuated Equilibria:A type of
evolution that occurs rapidly in
short bursts of time.
Gradualism: A type of
evolution that occurs slowly
over a long period of time.
What are homologous structures?
Similar structures that related
species have inherited from a
common ancestor.
Why do evolutionary biologists
think that related species have
similar body structures and
development patterns?
The organism has inherited many of
the same genes from a common
ancestor.
1.What does this branching tree diagram show?
2. Are turtles more closely related to modern birds or mammals? How do
you know?
3. Name a common ancestor of crocodilians and turtles.
1.It shows how scientists think that
groups of organisms are related.
2. Modern birds…they are closer
together on the diagram.
3. First Reptiles.
What is natural selection?
The process by which organisms that
are better adapted to their
environment are more likely to
survive to reproduce.
What is overproduction?
When a species produces
more offspring than can
survive.
Genetic (genotype and phenotype)
differences between members of the
same species is called________
Variation
How does natural selection lead to
evolution?
Some traits are helpful and give
certain individuals a survival
advantage. These beneficial traits
accumulate because the members of
a species that have these traits have a
greater chance of successfully
reproducing thus passing their
genetic info. to their offspring.
What is a species?
A species refers to a group of
organisms with similar traits that can
breed and produce fertile offspring.
What is an adaptation?
An adaptation is an inherited
characteristic that improves an
organisms chance for survival.
What are the four factors that effect
natural selection?
1. Overproduction
2. Variation (genetic)
3. Selection (aka Successful
Reproduction)
4. Competition for limiting
factors (food, water, space,
mates, sunlight, etc.)
Can natural selection occur without
variation (support your answer)?
No. Without genetic variation, all
individuals within a species would
have a equal chance of survival.
1.If the half-life of an isotope is 8
days, how long will it take for ¾ of
a sample to decay?
2. Would you use Carbon-14 to try
to find the age of a fossil from the
cretaceous period? Explain.
Part 1:
16 days
For instance:
You start with 100 grams.
After 8 days=50 grams
After 16 days=25 grams (3/4 of what you
started with).
Part II:
No…the half life of C14 is 5,730 years…too
short. You’d want something like Uranium
235; it has a longer half life.
1. Most of what we know about
extinct organisms is based
upon________
2. In which type of rock do you find
fossils.
1.The fossil record.
2. Sedimentary
Whatz up with those peppered moths
(they sound delicious)?
Well, in England during the industrial revolution,
there were these moths. They were the light colored
moths were camouflaged against the tree bark on
which they hung out.
Gradually, soot from the emerging industrial
processes started to darken the tree bark. Moths that
were lighter in color began to be more easily seen by
predators, and the darker colored moths were now
better camouflaged (it used to be the opposite). This
illustrates how a once beneficial trait can become a
detriment as the environment changes.
How old is the Earth?
4.5 Billion Years Old
During which geologic time period
did life first occur?
Precambrian Time