STICKLEBACK LAB – DAY 1

Introduction to Stickleback Evolution

STICKLEBACK EVOLUTION VIDEO

https://www.youtube.com/watch?time_continue=2&v=Pv4Ca-f4W9Q

HHMI STICKLEBACK VIRTUAL LAB

• Complete the Introduction, Overview, and Tutorial• Answer questions 1-8 on your lab sheet

CHECK FOR UNDERSTANDING

HHMI STICKLEBACK VIRTUAL LAB

• Complete the Experiment 1• STOP when you reach Experiment 1 Analysis• Answer questions 9-23 on your lab sheet

*For the graph (#20), click the very bottom “click here” for the computer generated graph after you have totaled all of your data.

HHMI STICKLEBACK VIRTUAL LAB

HHMI STICKLEBACK VIRTUAL LAB

• Null HypothesisThe expected observation in nature.

In a classroom, we expect there to be 50% boys and 50% girls.

The Null Hypothesis would be:There are equal numbers of boys and girls in the classroom.

HHMI STICKLEBACK VIRTUAL LAB

• Null HypothesisWhat is the null hypothesis for this lab?

There are an equal number of fish with pelvic spines present and absent in the lake.

What is the data?

Bear Paw Lake Frog Lake Morvoro Lake

Pelvic Spines Present 0 20 8

Pelvic Spines Absent 20 0 12

Day 1: Stop here if not doing Chi-Square Analysis.

HHMI STICKLEBACK VIRTUAL LABCHI-SQUARE CALCULATIONS

Bear Paw Lake

Phenotype Observed (o) Expected (e) (o-e) (o-e)2 (o-e)2/e

Pelvic Spines Present

Pelvic Spines Absent

Total = Total = X2 =

HHMI STICKLEBACK VIRTUAL LABCHI-SQUARE CALCULATIONS

Frog Lake

Phenotype Observed (o) Expected (e) (o-e) (o-e)2 (o-e)2/e

Pelvic Spines Present

Pelvic Spines Absent

Total = Total = X2 =

HHMI STICKLEBACK VIRTUAL LABCHI-SQUARE CALCULATIONS

Morvoro Lake

Phenotype Observed (o) Expected (e) (o-e) (o-e)2 (o-e)2/e

Pelvic Spines Present

Pelvic Spines Absent

Total = Total = X2 =

HHMI STICKLEBACK VIRTUAL LAB

• Degrees of Freedom – the number of items in a set minus one.

• Set = Phenotype• Number of items: 2 – Pelvic spines present and Pelvic spines absent

• Degrees of Freedom = (when your class reaches the answer, type here)

HHMI STICKLEBACK VIRTUAL LAB

Lake p value Null hypothesis

Bear Paw Lake

Frog Lake

Morvoro Lake

STICKLEBACK LAB – DAY 2

Stickleback Defense Lab

STICKLEBACK PREDATORS

• Answer question 1

DEFENSE LAB

• Look at the Stickleback Fish Image Set• Sort the fish into two groups based on what you learned from the digital

lab

• Answer questions 2 and 3

ARMOR PLATES

• The armor plates protect the fish in different ways, including:• Resistance to penetrating attacks• Increasing swallowing difficulty and damage to soft mouthparts of

predators

• Increasing body size when spines are erect• (Song et al. 2010:329)

ARMOR PLATES

• There is consistent data that supports the hypothesis that if a stickleback lives in a marine environment, it will have more armor plates than stickleback in freshwater.

• Why do you think a marine stickleback needs more armor plates?

• Answer questions 5-6 on your lab sheet.

*To calculate average: Add up the number of plates in one category and divide by the number of specimens in that category.

ARMOR PLATE GRAPH

MARINE FRESHWATER

DEFENSE LAB

• Use the class T-Chart and the graph on your paper to answer questions 10-12.

STICKLEBACK LAB – DAY 3

Stickleback Gill Rakers Lab

WHAT ARE GILL RAKERS?

LAKE STREAM

GILL RAKERS

ANSWER QUESTIONS 1&2

NOTE. IMAGES NOT TO SCALE.

GILL RAKERS

• Stream fish tend to eat invertebrates while lake fish tend to eat plankton

• The morphology (or shape and structure) of the Gill Rakers help the lake fish catch food.

• Think of Baleen Whales

GILL RAKERS DATA COLLECTION

• Count the number of gill rakers on each fish and record the number.

• Decide if the fish is from the lake or stream• Answer questions 3-5

Part IV. Compare these gill rakers

Lake 1: Kennedy Lake Lake 2: Swan Lake

Part IV. Compare these gill rakers

Lake 1: Kennedy Lake Lake 2: Swan Lake