Human Evolution Evidence for Evolution Ideas that shaped Darwin’s thinking

Ideas that shaped Darwin’s thinking Prior to Darwin’s Theory of Evolution there were 4 scientists that had their own ideas and theory’s 1. Hutton 2.Lyell 3.Lamarck 4. Malthus The Rock Boys!! The Math guy!

James Hutton Helped scientists understand that Earth is many millions of years old Processes that changed the Earth in the past are the same processes that operate in the present

Charles Lyell In Lyell’s book: Principles of Geology Rock Cycle: Volcanoes and Earthquakes Erosion continues to carve out canyons.

Uniformitarianism Uniformitarianism: the natural laws and processes that operate in the universe now, have always operated in the past. How do you pronounce that?? Uniformitarianism

Jean-Baptiste Lamarck Use or disuse of organs, organisms acquired or lost certain traits during their lifetime. Traits could then be passed on to their offspring.

Thomas Robert Malthus Malthus reasoned that if the human population continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone. Do you remember: Density Independent factors Density dependent factors

Thomas Robert Malthus He theorized that there was a “carrying capacity” in every habitat/ environment Populations will naturally get checked by famine, disease etc.

Darwin’s Theory of Evolution 1. Change over time, common ancestor Pre-existing variation 2. Variation within a population or species Everyone is just a little different 3. Natural selection Survival of the fittest

Darwin’s Evidences 1. Fossil Record 2. Geographical Distribution Yes, I can prove it! 1. Fossil Record 2. Geographical Distribution 3. Similarities in Structure Homologous/Analogous Structures 4. Vestigial organs 5. Similarities in Early development Embryology

1. Fossil Record Preserved remains or markings left by organisms that lived in the past are called fossils.

Position of fossils can reveal their age. Younger Older

2. Geographical distribution Organisms in different parts of the world shared similarities

3. Vestigial Organs Organs of many animals are so reduced in size that they are just vestiges, or traces, of homologous organs in other species I have toe nails!!!

4. Similarities in structures Homologous structure: same basic structure but different function Analogous structure: same basic function, but do not have the same basic structure

Homologous Homologous structures: similar structures but have different function Derived from a common ancestor Ex. Forelimb

Analogous Analogous structures: similar function but not similar in structure Not derived from a common ancestor Ex. A butterfly wing and a bird wing

5. Similarities in Early development Common pattern in the development In their early stages, chickens, turtles, and rats look similar, providing evidence that they shared a common ancestor

Lets Play a Game Adopt an Embryo! Select one embryo to adopt as your own!!

Class Activity Adopt an Embryo! 1 2 3 4 5 6 7 8

Adopt and Embryo Stage 2 1 2 3 4 5 6 7 8

Adopt an Embryo Stage 3

Darwin’s Evidences Review Yes, I can prove it! 1. Fossil Record 2. Geographical Distribution 3. Similarities in Structure Homologous/Analogous Structures 4. Vestigial organs 5. Similarities in Early development Embryology

Homologous vs. Analogous Activity Homologous Structure Analogous Structure Same Structure different function Same function different structure Instructions: Read Define Color Chart Answer Questions