Changing Over Time

Rich Stein

Carolina: Inquiries in Science Series

• Kit is set up for 6 groups• Three Activities– Activity 1: Students compared relatedness of

species– Activity 2: Homologous vs. Analogous vs. Vestigial

Structures.– Activity 3: Evolution of Antibiotic Resistant

Bacteria• Cost: $149.95

Instructional Approach

1. Focus

2. Explore

3. Explain

4. Apply

Focus

• Activities designed to help students study the evidence of evolution.

• Homologous Structures: structures evolved from a common ancestor.

Focus

• Analogous Structures: Differ in form but are similar in function. Organisms adapted in similar ways.

Focus

• Vestigial Structures: Remaining components of structures that once served a function in an organism’s ancestor but useless today.

Explore

• Kinship Activity: Within each row list the species that does not belong.

• 1: Raccoon• 2: Shark• 3: Sponge• 4: Toadstool• 5: Amoeba• 6: Leech

Explore

• Changing Over Time Structure Cards– Brainstorm with your group into how to organize

your cards– Consider:• Function of structures• Shared structures• Shared functions

Explore

• Homologous Structures:– Pitcher plant, Venus flytrap, Red poinsettia, and cactus

• Analogous Structures:– Human Legs and Spider Legs– Butterfly wings and bird wings– Vertebrate cranium and the anterior exoskeleton of

beetles.• Vestigial Structures:– Hind bones of whales, wings of ostrich, Dandelion

flower (ovules develop into seeds, no pollen needed)

Explore

• Activity 3: You’ll need– Luria Broth with E. coli – Pipet– Prepared ACG agar plate

• “Ampicillin concentration gradient”

• Write your group name• Pipet three drops of luria broth onto the ACG plate.• Let the plate sit for 10 minutes, then place into 37o

incubator for 24 hours.

Apply

• You have at your disposal:– LB Agar Plates– LB Agar + Ampiciliin Plates– Blank sterile antibiotic disks– Design an experiment to test your hypothesis