Review for standard 5

Evolution

How did DNA discoveries help evolution?

• Remember biochemistry

• Now we could look at similarities in DNA sequences and revise how things are evolutionary trees.

Darwin – 1800s• Natural selection • Darwin create theory of evolution alone?• No Darwin built upon ideas of other scientists like

Wallace• Originally not accepted but is now accepted.

Why?• Lots of evidence that supports his theory like

what?• Fossils, anatomy, biochemistry and embryology• Different species of finches found on different

islands • Reproductive isolation

Evidence for evolution

• Adaptations

• Like mimicry and camouflage

• Fossils

• Embryology – embryo of fish,reptiles, birds and mammals are similar

Embryology

Homologous Structures

• Similar in arrangement, function or both. – COMMON ANCESTOR

• Divergent evolution

Analogous Structures

• Body parts are similar in function but –

• DO NOT HAVE COMMON ANCESTOR

• Convergent evolution

evidence for evolution

• homologous structures common or not common ancestor?

• Common evolutionary origin

• Divergent or convergent evolution?

• divergent evolution.

• analogous structures common or not common ancestor?

• Not common • Convergent or

divergent evolution? convergent evolution

Evidence for evolution

• Evidence that present species developed from earlier forms.

• AUG codes for methionine in all living things

• Why would I not care about one single mutation in a population.

• Survival is not threatened by this as there are ways usually ways to adapt

What is relative dating?

• Fossils in deeper rock layers are older than those found closer to the surface.

• Why do scientists believe this?

• They assume that in the past, layers of sediment were deposited on top of each other the same as it is today.

If I find fossils of coral in one of these layers then I assume what?

• The area was once covered by an ocean

• Further evidence would be?

• fossilized shark teeth.

Geographic Isolation• What is it? • separation due to a physical barrier like a river or

mountain divides a population eventually leading to speciation –

geographic isolation

• Example is frogs separated by a mountain or a river

• What can this lead to?• Speciation. • What is speciation?• No longer interbreed and produce fertile offspring• Convergent or divergent evolution?• divergent evolution

Reproductive Isolation

• What is it?• two organisms become isolated reproductively.• What does this lead to?• Speciation • What is speciation?• so different (for whatever reason) that they can no

longer interbreed and produce fertile offspring.• This is what happened with Darwin’s finches.

What happens during geographic or reproductive isolation?

• Something divides a population so that they can no longer mate

• which can lead to?

• Speciation.

• Divergent or convergent evolution?

• Divergent evolution

Classification (common name vs. scientific name)

• Linnaeus what did he do?• Two-word naming system (scientific name) • First word is?• genus, (Capitalized like Homo sapien)• second word is?• a descriptor• In Italics and first letter of first word is capitalized• Like Felis concolor is scientific name for common

name of mountain lion

Whittiker – 5 kingdoms

• Can you name them?

• Plant

• Animal

• Fungi

• Protist

• Monera (bacteria)

6 kingdom

• Same but monera (bacteria) is divided into two groups

• Eubacteria

• Archaebateria

• Which kingdom is prokaryotes

• Monera (bacteria)

Changes, changes, changes

• Why do we keep changing things?

• Science always revises its ideas as new stuff is always being discovered

Time line

• Time line - one million years equals one meter. Problem?

• The time line will be too long to fit in the classroom.

Name the taxas

• Kingdom

• Phylum

• Class

• Order

• Family

• Genus

• Species

•Which is most DIS-similar (broadest group) from each other ?

•Toward Top - Kingdom

Which ones are the most SIMILAR (most specific)

Towards bottom (Species)

Dichotymous keys

Does science ever change?

• Yes. - Think of the classification systems

• Carolus Linnaeus – 2 word naming system

• Robert Whittaker – 5 kingdom system

• And now??? 6 kingdoms ?????

• Why all the changes?

• As we find out more stuff, we have to revise.

What do you remember about Darwin?

• Galapagos islands – 1800s - finches

• Isolation – Geographic and Reproductive

• Natural selection

Did Darwin create the evolution theory by himself?

• No. He used ideas of others• Like who?• Wallace.