EVOLUTION: An Introduction

EVOLUTION Chapter 13: Evolution: Evidence of Change Chapter 14: Evolution: How Change Occurs (Process of Evolution)

EVIDENCE OF EVOLUTION: 1.Ability to artificially select (breed) 2. Geographic distribution of similar species Family Culicidae a.k.a. ___________? Canis lupus

EVOLUTION: Evidence Of Evolution 3. Fossil Record 4. Homologous structures show common ancestors (Comparative Anatomy)

EVOLUTION: Evidence Of Evolution 6. Embryology: development of embryonic structures (developing embryos undergo evolutionary changes)

EVOLUTION: Evidence Of Evolution 7. Chemical Relationships: - DNA - amino acids in protein e.g. cytochrome c hemoglobin

8. vestigial organs: organs that an organism has no use for (may resemble miniature legs, tails, etc.) as evolutionary change takes place, species develop new adaptations that make some organs unnecessary (e.g. snakes have leg buds implying that their ancestors had feet, Figure , p. 285)

Evolution and Life’s Diversity Evolution: - the process by which modern organisms have descended from ancient organisms - Charles Darwin contributed the most to evolution

Darwin’s Dilemma Englishman ( ) he studied animals while cruising the world on the HMS Beagle collected animal and plant specimens wrote and read many books on his voyage

Diversity of Life the variety of living things is called the diversity of life how many organisms exist on earth? (~3-20 million different living species) Darwin discovered that many organisms had vanished from the Earth Dodoes are now extinct

Fitness: To Survive and Reproduce the physical traits and behaviours that enable organisms to survive and reproduce in their environment give them what Darwin called fitness Darwin published his theory in 1859, 30 years after his voyage began, in his book entitled “The Origin of Species” charles/the-origin-of-species-6th-edition/

Fitness: To Survive and Reproduce Principle of Common Descent: species have descended from common ancestors fitness arises through adaptation (e.g. giraffes developed long necks over time leading to the giraffe we know today)

Summary the observations of the diversity of living things on earth contributed to the formation of Darwin’s theory of Evolution fitness is the combination of physical traits and behaviours, or adaptations that help organisms survive

The Age of The Earth: The Geological Time Scale: A Clock in the Rocks geological time scale: helps biologists and geologists date the Earth’s past with the help of a record in the rocks relative dating: a technique scientists used to determine the age of fossils relative to other fossils in different layers of rock

The Age of The Earth: Radioactive Dating radioactive dating: the traces of radioactive isotopes enable scientists to calculate the actual age of a sample scientists estimate that the Earth is 4.5 billion years old scientists divided the 4.5 billion years into Eras ( Cenozoic/Mesozoic/Paleozoic /Precambrian) …Periods…Epochs… (Can’t Make People Perfect)

The Fossil Record How Fossils Form the material surrounding the dead organism often preserves it most fossils are found in sedimentary rock sedimentary rocks are formed when exposure to rain, heat, and cold breaks down existing rocks into small particles of sand, silt and clay these particles are carried by streams and rivers and they settle at the bottom of the lake or sea

Evidence from Living Organisms all living organisms carry within their bodies traces of the history that links them to their ancestors