Learning Target: I can describe Charles Darwin’s observations and explain the theory of evolution I can identify whether adaptations are behavioral or structural and explain how they help an organism survive in its environment

EVOLUTION NOTES Part 1

Evolution = Change in species over time All life has a common (shared) ancestor and ALL species change

Species = Distinct group of organisms that can interbreed (have babies) – physical, behavioral, & molecular similarities *Theory = Best explanation based on much evidence *Continuous (organisms keep changing, depending on needs in environment

I. History of Evolution

A. Charles Darwin (1809-1882)

1. Sailed around the world on the HMS Beagle, 1831-1836

2. Naturalist – carefully observed living things

3. Most important visit: Galapagos Islands: Group of small islands west of South America with unique environments

B. Darwin’s Observations 1. Organisms on each island were unique and adapted to their environments a. Adaptation = Trait that helps an organism to survive in its environment

Types of Adaptations: i) Behavioral: Things organisms DO Ex: Migrating; Being nocturnal; hibernating ii) Structural: Physical characteristics Ex: Defensive structures (thorns, teeth) Color/camouflage

2. Darwin’s Finches – small birds on each island a. Had a common ancestor – finches from the mainland b. Beak shape changed according to food type

3. The Origin of Species  a. Darwin’s book published in 1856 b. Described his theory that all organisms are constantly changing in response to their environment

Video Assignment Use your notes and details from the videos to write a 1-2 paragraph essay on this topic: How did Charles Darwin’s study of birds help him develop his theory of evolution? What is evolution, and why does it happen? How do we know it happens? What does it tell us about all life on earth? Due 4/10 (Weds)

Video 1: http://www.youtube.com/watch?v=GhHOjC4oxh8 http://www.youtube.com/watch?v=l25MBq8T77w *Due tomorrow 4/10!

LEARNING TARGET I can explain how the fossil record, anatomy, and other evidence support the theory of evolution

Notes continued… Halfway down page 2

II. Evidence for Evolution A. Comparative Anatomy (Body structure) 1. Homologous Structures – body parts that have different functions but developed from similar body parts Ex) Human arm bone / Bat wing / whale flipper

2. Vestigial organs – parts that have lost their function Ex) Human appendix – other animals need it for digestion Leg bones in snake Pelvis in whales

B. Similarities in Development 1 B. Similarities in Development 1. Embryo – organism in very early stages of development 2. Early embryos of most species are almost identical (tail, gill slits, etc.)

C. Fossils – Evidence of dead organisms (ex C. Fossils – Evidence of dead organisms (ex. bones, shells) that are hardened and preserved

1. Intermediate/ “in-between” fossils show that different species are related Ex) Archaeopteryx – small dinosaur with feathers Ex) Tiktaalik – “fish with legs”

2. Fossils of current animals show change over time Ex: Horses used to be smaller with separated toes Ex: Humans had ancestors that were similar to apes

D. Similarities in chemical compounds 1 D. Similarities in chemical compounds 1. All organisms share same basic chemicals: *DNA, carbon, hydrogen, oxygen, amino acids 2. Comparison shows relationships of organisms Ex: Dog & wolf DNA is 98.8% similar!

And now… Close & Critical Reading about a real discovery about Evolution from a few years ago! Please answer the survey questions at the beginning and end *Due tomorrow 4/11!