EVOLUTION This image is WRONG Yet its still

EVOLUTION This image is WRONG! Yet its still what most people think of when someone discusses evolution. Brainstorm with your neighbor what might be incorrect with this depiction of evolution

STEP #1 We’re all Different • Organisms that reproduce sexually produce genetically unique individuals. • We are all slightly different from one another. • New traits are brought about by new genetic combinations either from fertilization or from mutations • New traits are called mutations

What causes populations to change?

STEP #2 Environmental Changes • If the environment changes some organisms will be more likely to survive

The following slide depicts a population of circles. Circles are either blue or tan. On the next slide count the number of blue circles

ENVIRONMENT #1

The environment has changed On the next slide, count the number of blue circles

ENVIRONMENT #2

Questions 1. What could your counting have simulated? (why is it good to blend in? ) 2. Which circle, tan or blue was originally (environment 1) suited for its environment? 3. Why were they more “fit” in that environment 4. What will likely happen to the population of circles now that there has been an environmental change?

STEP #3 Survival of the Fittest • If the environment changes some organisms will be more likely to survive • Not all mutations are beneficial. – If a mutation helps an organism survive it is called an adaptation. – Not all mutations are adaptations. Examples? Is it a mutation or an adaptation?

Mutation or Adaptation? • A racehorse is born with longer legs.

Mutation or Adaptation? • A fish is born with a smaller deformed fin.

Mutation or Adaptation? • A chicken is able to lay more eggs than others

Mutation or Adaptation? • A baby is born without his right eye

Mutation or Adaptation? • A baby is born without his right eye

STEP #4 Dead organisms don’t have sex • Those best adapted to the changed environment will survive to reproduce. • Their offspring will inherit the gene for their adaptation.

THUMBS!!! • Have your partner use a stopwatch to time how long it takes you to write the alphabet on a piece of scrap paper. • Use a rubber band (or tape) to attach your thumb to its neighboring finger. Disable your thumb. • Repeat the alphabet. WILL YOU SURVIVE?

This process is called: Natural Selection • Natural selection: process by which individuals with inherited characteristics well-suited to the environment leave more offspring on average than other individuals SURVIVAL (and reproduction) OF THE FITTEST

So how did we get so much variation? • Descent with modification: Descendents of earliest organisms spread into various habitats over million of years. In these habitats they accumulated different modifications or adaptations to diverse ways of life example Jack rabbits/snow rabbits

Giraffe’s Neck Example

Did they stretch out their necks?

In reality

How’d that Happen? ?

Long Ears? • Not just for hearing! What else?

Shell Shape? • Crabs are predators of snails

Beak Shape?

Antibiotic Resistance?

Long Necks?

Color?

This guy versus That guy Unlike most other people at that time, “That guy” and “This guy” both thought that life had changed gradually over time and was still changing, that living things change to be better suited and adapted to their environments, and that all organisms are related. “That guy” and “This guy” also agreed that life evolved from fewer, simpler organisms to many, more complex organisms.

“This guy” is best known for his Theory of Inheritance of Acquired Characteristics (If an organism changes during life in order to adapt to its environment, those changes are passed on to its offspring. ) He said that change is made by what the organisms want or need. For example, “This guy” believed that elephants all used to have short trunks. When there was no food or water that they could reach with their short trunks, they stretched their trunks to reach the water and branches, and their offspring inherited long trunks. “Old What’s his name” also said that body parts that are not being used, such as the human appendix and little toes are gradually disappearing. Eventually, people will be born without these parts. He also believed that evolution happens according to a predetermined plan and that the results have already been decided.

• “This guy” believed that giraffes stretched their necks to reach food. Their offspring and later generations inherited the resulting long necks.

“So and So” believed that the desires of animals have nothing to do with how they evolve, and that changes in an organism during its life do not affect the evolution of the species. He said that organisms, even of the same species, are all different and that those which happen to have variations that help them to survive in their environments survive and have more offspring. The offspring are born with their parents' helpful traits, and as they reproduce, individuals with that trait make up more of the population. Other individuals, that are not so well adapted, die off. Most elephants used to have short trunks, but some had longer trunks. When there was no food or water that they could reach with their short trunks, the ones with short trunks died off, and the ones with long trunks survived and reproduced. Eventually, all of the elephants had long trunks. “Whats his name” also believed that evolution does not happen according to any sort of plan.

So what’s what?

• If you practice everyday and become very good at lacrosse will your children be good at lacrosse? • If I hung upside down in my closet holding weights until I stretched 2 inches will I have taller children? • If you sit out in the sun and develop skin cancer, are your children more likely to have cancer?

• • Peppered Moth Simulation Lab Discussion Isolation Mechanisms Start Evidence for the Theory of Evolution – – – • Comparative Anatomy Vestigial Structures Embryo Studies Fossil Evidence Biochemistry Evidence HW – second page of review and vocabulary • WOD: Homologous/Analogous Structure, Vestigial Organ

Practice Natural Selection • http: //www. techapps. net/interactives/pepp er. Moths. swf • Google: “Peppered Moth Simulation”

• • • Woolyboogers Lab Evidence of Evolution Debrief from Lab Cladograms Quick Overview Time to finish study guide and vocabulary • HW – Finish study Guide and Vocabulary, TEST tomorrow • WOD: Fitness

That’s all good and swell… but prove it! Evolution is a THEORY that must be taught in the curriculum and will be tested on the Keystone Exam Theories are backed up by evidence

What is a theory • https: //www. youtube. com/watch? v=3 v. KJM Fta 6 v. I

Evidences of Evolution 1. Comparative Anatomy 2. Vestigial Organs 3. Embryo Studies 4. Fossil Evidence 5. Biochemistry -Amino Acid Sequences and DNA studies

Comparative Anatomy The more similar in structure 2 organisms are the closer related they are.

Compare these 4 skeletons: Human Frog Bird Cat The Skeletons of these organisms are on the next slides. Study them and determine which organism is more closely related to humans. Be prepared to defend with evidence!

HUMAN

FROG

CAT

BIRD

Compare these 4 skeletons: Human Frog Bird Cat Determine which organism is more closely related to humans. Be prepared to defend with evidence!

Two Types of Structures: • Analogous Structures: – Same FUNCTION, Different STRUCTURES – WHAT ARE SOME EXAMPLES? • Homologous Structures: – Same STRUCTURE, Different FUNCTIONS – WHAT ARE SOME EXAMPLES?

NOT EVIDENCE Analogous Structures that have the same function but developed differently.

Compound Eyes Versus our Eye

EVIDENCE FOR EVOLUTION Homologous Structures that have different functions but developed similarly.

Vestigial Organs: organs that no longer have a function. 1. Tailbone 2. Appendix 3. Body Hair 4. Tonsils 5. Wisdom Teeth 6. Little Toes

What do you need to remember? • Biotechnology – Cloning – Gene splicing – Gene therapy – Gel electrophoresis • Evolution – 4 steps – Synonym – Decent with modification – Evidence • Comparative Anatomy • Vestigial Organs

Embryo Studies The more closely related 2 organisms are the more similar their embryo development.

Compare Chick & Piglet

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

What am I? ? Human, Monkey, Pig, Chicken, or Salamander

Fossil Evidence 1. The older the fossil, the more further down in the rock layer. 2. The closer two fossils are the more closely related the species are.

Which organism is oldest, youngest? D C B A

Pangea: Moving Continents Similar fossils found in different parts of the world suggest those fossils were once together WHY IS THIS EVIDENCE? .

Biochemistry The more closely related 2 organisms are to each other, the more similar their biochemistry (amino acids and DNA)

Comparing Amino Acids Human Gorilla Horse Alanine Leucine Proline Serine Leucine Proline Valine Serine Proline Alanine Serine Alanine

DNA Studies The more similar 2 organisms’ DNA are, the more closely related they are.

DNA Gel Electrophoresis Human 1 2 ______ 3 ______ 4 5 ______ Horse Gorilla ______ ______

CLADOGRAMS diagram used to organize evolutionary relationships

• Evolution and Biotechnology TEST • Begin ECOLOGY (starts in book on page 51) • Biomes • HW – Biomes Homework • WOD: Cladogram, Ecology, Biomes