Semester 2, Day 13

Fossil Evidence of Evolution

Agenda Review for Quiz on Speciation and Isolation Turn in Homework Take Quiz on Speciation and Isolation Lecture on Fossil Evidence of Evolution Break Reading/Work Time

Review for Quiz on Isolation and Speciation Gradualism theory of evolution (from book) Punctuated equilibrium definition (from book) Definition and Process of Speciation Definition of Prezygotic and Postzygotic

Isolation Types of Isolation. Are they Pre or Post?

Understand definitions and examples Behavioral, Gametic, Hybrid Inviability, Habitat

Isolation, Hybrid Breakdown, Geographical, Spatial, Mechanical, Hybrid Sterility, Temporal

Homework Due Cornell Notes on Section 15.2 Pg 409-413 Questions:

15.2 #2-5 Chapter 15 Assessment #3, 4, 8, 11, 15, 21-24

Take Quiz Silence during quiz Eyes on your own paper Flip over when finished

Fossil Evidence of Evolution

Part 1: Theory

Part 2: Evidence

Fossil Evidence of Evolution Fossil: preserved evidence of an org.

Fossil Evidence of Evolution Trace Fossil: Indirect evid. left by org. (footprints, burrows,

fossilized feces)

Fossil Evidence of Evolution Mold Fossil: Impression of an org.

Fossil Evidence of Evolution Cast Fossil: Mold filled w/ sediment

Fossil Evidence of Evolution Replacement Fossil: Original material replaced by crystals,

detailed replicas

Fossil Evidence of Evolution Petrified Fossil: Empty pore spaces filled in by

materials

Fossil Evidence of Evolution Amber Fossil: Preserved tree sap traps entire org . Hardens

into amber.

Fossil Evidence of Evolution Original Material Fossil: Mummification or freezing preserves

original orgs.

Fossil Evidence of Evolution Most decompose before fossilized

Those rapidly buried in sediment are preserved Sediment: minerals or organic matter (dirt, sludge, etc.)

Fossil Evidence of Evolution Drawing

Igneous Rocks: magma cools Metamorphic Rocks: extreme heat & pressure Sedimentary Rocks: minerals & sediment accumulate

Nearly all fossils are SEDIMENTARY (can’t survive ht or pres.)

Fossil Evidence of Evolution Fossil Record: fossils in earth’s layers; major

events in hist. of life. Strata: dif. rock layers

Same age strata have same fossils no matter where layer is

Fossil Evidence of Evolution Fossil Record (cont.)

Dramatic speciation after mass extinctions Mass Ext.: many species die out at once Speciation: new species evolve

Fossil Evidence of Evolution Based on fossil record, scientists think that:

The earth is ~4 bil. yrs old

Dating Fossils Relative Dating (LAW OF SUPERPOSITION)

Old strata below new strata

Radiometric Dating Decay of radioactive chemicals

Fossil Evidence of Evolution Work Sheet

Fossil Evidence of Evolution Geologic Time Scale: major geo. & bio. events

in Earth’s hist.

Precambrian

1st life = ~3.4 bil. yrs.

87%

Beg: 1 cell

prokaryotes (no

nucleus)

End: multi Cellular

eukaryotes

Cambrian Explosion of

ocean animals, “Age of Marine

Life”

“Age of Reptiles”

Mass Extinction of marine

animals (90%)

Mass Extinctionof dinosaurs

“Age of Dinosaurs

“Age of Mammals”

Fossil Evidence of Evolution Think about a year…

Jan Feb Mar Apr May June Precambrian

July August Sept Oct Nov Dec

Precambrian Paleozoic

Mesozoic

Cenozoic

HumansJan Mid-Oct

Mid-Oct Dec 10

Dec 10 Dec 26

Dec 26 Dec 31

Evening on Dec 31st

Fossil Evidence of Evolution Pangaea

Began as 1 land mass Sep. over time

Orgs. on dif. continents can be very similar Will meet on other side to make a new

supercontinent

Fossil Evidence of Evolution Amasia: collision of North America and Asia

BREAK

Reading/Work Time Cornell Notes Section 14.1 pgs. 375-379 Questions:

14.1 #1-5 Chapter 14 Assessment #3, 6, 9, 10, 12, 18-20

Remember! 3 out of 5 checked for accuracy and completion Less than 3/5 on HW = 0 on quiz until corrected