1. Evolution

2. Evolution:
The generation-to-generation change in the proportion of different inherited genes in a population that accounts for all of the changes that have transformed life over an immense amount of time

3. In science … THEORY is defined as an overarching explanation of some aspect of the natural world that has been well substantiated.

4. Oh dear, natural selection is at it again!
Gary Larsen

5. Evidence of Evolution
Biodiversity and the Geologic Distribution of Organisms
The Earth has changed over time, resulting in certain distribution patterns and common ancestry of species
Embryology
Similar early development indicates similar genetics, which in turn indicates common ancestry

6. Evidence of Evolution Vestigial Structures
Some organs & structures become unnecessary as species evolve

7. Evidence of Evolution
Fossil

8. Fossils

9. Transitional Fossils

10. Evidence of Evolution DNA & Proteins Homologous Structures
The code of life is universal
Similarities and differences help put together a picture of the evolutionary family tree
Homologous Structures
Similar internal structure indicates common ancestry

11. Homologous Body Structures
Section 15-3
Homologous Body Structures
Turtle
Alligator
Bird
Mammals
Typical primitive fish

12. Homologous Body Structures

13. Vertebrate Hemoglobin

14. Mechanisms of Evolution
Mutations
Changes in DNA that are not fatal or harmful create variation within species that results in differential survival of individuals – “survival of the fittest”

15. Mechanisms of Evolution
Natural Selection
The process by which individuals with beneficial inherited characteristics (adaptations) survive better and therefore reproduce more than other members of the species

16. Requirements for Natural Selection
Variation within a species of inheritable characteristics – beneficial characteristics are called adaptations
Overproduction of offspring causing competition for resources
Differential survival and reproduction of individuals over many generations