Evolution Part 2: Evidence & Types

Evolution Part 2: Evidence & Types

Common Descent with Modification

Darwin proposed that organisms descended from ______

Organisms change over time, diverging from the common form

Caused ______: evolution of new species

Descent With Modification

Takes Place Over Long Periods of Time

Natural Selection Can Be Observed As Changes In

Body Structures

Ecological ______(role of the organism in its environment)

Habitats

Implies

All Living Organisms Are Related

Single Tree of Life

DNA, Body Structures, Energy Sources

Common Descent - All Species, Living & Extinct, Were Derived From Common Ancestors

Theory of Evolution Today: Supporting Evidence

1. Fossil Record:

______= any preserved remain or imprint of once-living organisms found in layers of sedimentary rock

______

The fossil record is the ordered arrangement in which fossils appear within ______.

These rocks record the passing of geological time and provides an actual record of the Earth’s past life forms

2. ______

Structures that are ______in ______because of common ancestry (comparative anatomy)

Scientists Noticed Animals With Backbones (Vertebrates) Had Similar Bone Structure

May ______In ______

Limb Bones Develop In Similar Patterns

Arms, Wings, Legs, Flippers

3. ______

Structures that are ______similar in

Structure due to a common ancestor but instead are ______due to a common ______or habitat

Type of comparative anatomy

4. ______

Structures that are ______by the organism that have decreased in size and/or function

Examples: whale leg, ostrich wing, human appendix

5. ______

Study of structures that appear during embryonic development.

Organisms that are of a common ancestry will develop in a similar fashion

6. Geographic Distribution of Life forms

Different Animals On Different Continents But Similar Adaptations To Shared Environments

7. Molecular biology (biochemistry):

Study of ______(amino acids)

Organisms that are more closely related will have DNA that is more similar

Types of Evolution

______– the change of allele (DNA/gene) frequencies with in a population; small scale

Exp: Peppered Moths

______– large scale evolutionary changes

5 Patterns of macroevolution

1. Mass extinctions
2. Adaptive Radiation
3. Convergent Evolution
4. Coevolution
5. Punctuated Equilibrium (and gradualism)

5 Patterns of Macroevolution

1. Mass Extinctions

More than 99% of all species that ever lived are now extinct

Mass extinctions wiped out food webs and ecosystems

The primary factor that marks the ______of geologic ______.

2. Adaptive Radiation (______)

A species or group of species evolves into many new species with different adaptations

Exp: Darwin’s finches

3. ______

Unrelated species may evolve to resemble one another if they live in very similar environments. Show analogous traits

Example:

1. Ostrich (Africa) and Emu (Australia).

2. Shark, and dolphin (have streamlined bodies that allow them to swim rapidly)

4. ______

Evolutionary change, in which one species act as a selective force on a second species, inducing adaptations that in turn act as selective force on the first species.

Example: Humming birds and plants with flowers with long tubes

5. ______

Patterns of ______evolution after long periods of equilibrium (______)

Why? Migration, mass extinctions, isolation

How does it appear that GRADUALISM is different?

Gradualism is selection and variation that happens more gradually.