Unit 2: Evolution

Lesson # 9: Evidence for Evolution

Time for a Refresher

• What is the long, slow process of change in a species over time?

• A _________ is a group of similar looking organisms that breed with each other and produce fertile offspring make up a population.

• ___ ____ is the survival and reproduction of the organisms that are genetically best adapted to their environment.

Class Updates

• We only have 5 more classes until finals!

• Remember that finals are CUMULATIVE

• Journal and refresher questions might be on the test

Evidence for Evolution

Gray Wolf DNA

Sequence

ATT AAG CCG ATA

Shar-Pei DNA Sequence AAT GAA CCG ATA

Akita DNA Sequence ATT AAG CGG ATA

Husky DNA Sequence ATT GAA CGA ATA

Dingo DNA Sequence TTT GAA CGG AAA

Fossil Evidence

• The fossil record provides snapshots of the past thatillustrate evolutionary change over the past four billion years.

• There are some gaps in the fossil record

• Fossil evidence clearly shows that life is old and has changed over time

Comparative Anatomy

•Key Concept:

Comparing the

anatomy of different

organisms provides

clues about evolution

Homologous Structures

• Some organisms that

share a common

ancestor have features

that have different

functions, but similar

structures.

Homologous Structures

Analogous Structures

The wings of birds

and the wings of

dragonflies are

examples of

analogous structures.

An organ or structure that

likely once had a function in

an early ancestor• Examples

Vestigial Structures

Embryology

•Organisms develop similarly based

on shared ancestry

•During some stages of

development, organisms exhibit

ancestral features in whole or

incomplete form.

Embryology• What are some differences

between a:

• Fish

• Salamander

• Tortoise

• Chicken

• Pig

• Sheep

• Human

Embryology

Who is who?

A

B

C

D

E

F G

• Fish

• Salamander

• Tortoise

• Chicken

• Pig

• Sheep

• Human

Molecular Evidence

DNA Overview: http://statedclearly.com/videos/what-is-dna/

DNA Amino Acids Proteins

Molecular Evidence

•DNA Sequence Analysis

•Related species inherited the same

genes from a common ancestor

Gray Wolf DNA Sequence ATT AAG CCG ATA

Shar-Pei DNA Sequence AAT GAA CCG ATA

Akita DNA Sequence ATT AAG CGG ATA

Husky DNA Sequence ATT GAA CGA ATA

Dingo DNA Sequence TTT GAA CGG AAA

Overview and Review

• Stated Clearly: http://statedclearly.com/videos/what-is-the-evidence-for-

evolution/

• Evolution of Feathers: https://www.youtube.com/watch?v=hPLgfGX1I5Y