Adaptation: process by which an organism/population becomes better suited for their environment. Camouflage, Morphology, Behavior, Biochemical This unit will: explain the idea of “survival of the fittest” using the term adaptation/adapt.

Change Over Time Aka: Evolution

Theories of Evolution Evolution refers to change over time. Several scientists have contributed to the current theory of evolution. The theory is constantly changing-that is why it is a theory! Lamarck Similar species descended from the same ancestor  First to state that organisms change over time  Lamarck believed acquired traits were passed on to offspring and that is how species change over time  Passing of acquired traits was easy to disprove.

Who was Charles Darwin? Trained in the church but studied science. Took a job on the HMS Beagle as a naturalist traveling to South America and the Galapagos Islands for 5 years. Noticed finches in different areas had beaks that were suited for the food in that area.

Adaptive radiation: because of differences in the environment, many different forms of a speices emerge from a COMMON ANCESTOR

Darwin and Wallace Both proposed that species were changed by natural selection. The organisms that were best adapted to their environment would survive to reproduce. =fitness If a trait is favorable, what will happen to that trait in the population? If a trait is selected against what will happen to that trait? Evolution works on genes to change populations of species over time, not on individuals. What role do genes play???? If a phenotype is unfavorable in an environment, the genotype for that trait will decrease in the population. (BEAR LAB!!!)

Title: Natural Selection Lab / 40 pts. Question/Purpose: Background Paragraph: Read Story Define EVOLUTION. Define NATURAL SELECTION Answer Background Questions (in YOUR paragraph) Hypothesis: Write a possible answer to the question Draw Data Tables Read procedure!!! Now read it again and ask questions. Collect Data. Create a graph for the second table. ONE graph with THREE % lines. Conclusion Paragraph (honors) / Complete Sentences (Academic)

Review how Evolution by Natural Selection Works: Organisms would grow unlimited if it were not for the environment. The environment (nature) determines which traits are favorable or not so…The mechanism of evolution is natural selection. The most “fit” organisms will survive to reproduce and the SPECIES will change over time.

Types of Natural Selection Stablizing: the average trait is best Disruptive: both extreme traits are best Directional: one extreme trait is best Diagrams

Types of Natural Selection Stablizing: the average trait is best Disruptive: both extreme traits are best Directional: one extreme trait is best Diagrams Part B on your Worksheet – 5 minutes. Which type of selection is shown when insects become resistant to pesticides?

MRSA

Types of Natural Selection Stablizing: the average trait is best Disruptive: both extreme traits are best Directional: one extreme trait is best Diagrams Part B on your Worksheet – 5 minutes. Which type of selection is shown when insects become resistant to pesticides? How do organisms evolve so much they make a new species? Definition of a species: similar organisms that can reproduce to create fertile offspring

Making a new species •Requires isolation and evolution in different directions 1. Isolation can be because of a physical or behavioral barrier. –Physical - geographic isolation. –Behavioral- non-mating because of unrecognizable courtship rituals. 2. This results in divergent evolution (evolution in different directions) and eventually a new species.

How fast does change occur? Over long periods of time! Punctuated or gradual That is why we study organisms that reproduce FAST 

Co-evolution: organisms evolve together Convergent evolution: Unrelated species evolve similar traits because their environments are the same OR it is a really good trait! Co-evolution: organisms evolve together Ex. Flowers and pollinators

Darwin’s Evidence of Evolution Similar Structures (picture) Homologous Structures: same structure but used for the different function. Ex. Forearm of humans and the wing bones of a bat. Vestigial Organs Once very important but now reduced in size and function Ex. Human wisdom teeth or tailbone, hip bones in whales (picture) Embryology (picture) Many organisms that share a common ancestor look alike during development. Fossils Scientists use fossils to determine WHEN organisms evolved or what their ancestors looked like All of these pieces of evidence point to a COMMON ANCESTOR. Different ENVIRONMENTS produced differences in organisms. Now scientist use DNA and AMINO ACIDS to determine evolutionary relationships.

Evidence for Evolution Read the Introduction labeled WHY?. Use the evidence provided in Model 1 to answer questions #10-17 directly on the sheet OR in your notebook for more room. Complete sentences are not necessary. Add this to your table of contents and use to prepare for your quiz tomorrow! 30 minutes

Not all organisms evolve by NATURAL SELECTION: Discovery Video Clip https://www.youtube.com/watch?v=KkWC9KZc9Z0 Question: Do large, colorful tail feathers in male peacocks help the individual to survive or the species? Which is more important? Sexual Selection Selection of an individual based on certain traits that are favorable to the opposite sex but not necessarily favorable in the environment. Artificial Selection-humans decide the favorable traits. Ex. Dog Breeding, Agriculture