Download evolution notes 16

Welcome ! Today our 2nd to last unit
Evolution! - but first please dig out the
Genetics review sheet.
Welcome ! Today we do a good imaging
Lab on animal hands – please grab
Both lab sheets and look them over.
Google image pic of animal and x ray
Use Reid park zoo x rays for injured
Animals – you will prob need to look up
A pic of human skeleton – labeled. The
Bone names are the same as ours.
Evolution – a theory that
Explains how species change
Over time.
Theory – concept that has
Been repeatedly tested and
Used to make predictions
Evolution is still very
Controversial today – many
Other theories exist – Ex =
Creationism – religions etc.
This material represents
Theory only and material
On our regents exam. Some
States have laws about this.
Fossil records – help to
Explain history of life. The
Earth is around 4.5 billion
Years old.
Charles Darwin – theory of
Natural selection – said
Evolution was controlled by
Nature or the environment.
http://www.yo
utube.com/wat
ch?v=GhHOjC
4oxh8
Darwin – Natural Selection
Evolution = theory, organisms
Change over time, most change
is caused by the
Environment and nature.
Individuals that survive and
Reproduce have favorable
Traits or genes, and these
Traits are passed on.
Bad genes do not survive and
do not reproduce.
Rock mouse
https://www.yo
utube.com/wat
ch?v=sjeSEng
KGrg
Overproduction – species
Tend to produce more
Offspring than are needed,
Thus competition arises and
The best, strongest, best
Genes survive and are
Passed on = Survival of the
Fittest.
Genetic variation may
Produce some offspring with
A new favorable trait that
Helps it survive this is known
As adaptive value.
This trait is passed on =
evolution
Galapagos DVD video
Peppered moth lab
US Eugenics
https://www.yo
utube.com/wat
ch?v=IaH0Ws
8RtSc&index=
119&list=FLv8
6ZP7JCXSSP3
opJWTuxwg
Changes occur by mutations
And genetic shuffling during
Meiosis.
Genetic changes are either
Structural, functional or
behavioral
Structural change = organism
Evolves favorable new
Structures. Ex. Polar bears
Evolved extra fur on the
Bottom of their feet.
Functional changes = are
Molecular or biochemical
Changes that effect how an
Organism works.
Behavioral changes = how
An organism acts
Ex – expressway
crows ????
Patterns of change
Changes are often related to
Changes in the environment
Species with short life spans
And short reproduction
Change quicker
Failure to adapt to a changing
Environment will most likely
Result in the death of the
species.
The rate of evolutionary
change is most directly linked
To changes in the environment
Animal hands lab
Rapid changes do occur in
Organisms with short life
Spans and many offspring.
Ex.= many insects become
Resistant to pesticides after
A few generations
These fast reproducing
Organisms have a lot more
Chance of mutations
occuring
Larger organisms that pro-duce few offspring show
Much less change over time
Extinction – occurs when an
Entire species disappears,
Usually due to environmental
Changes.
Darwin did not have a
Complete understanding of
Genetics, he was unable to
Explain evolutionary change
Due to mutations and meiosis.
Summary - the environment
Causes most evolution – over –
Production causes survival of the
Fittest – a good trait that is passed
On has an ADAPTIVE VALUE
Fast reproduction rate = more
Mutations = more change-evolution