LAB #15: NATURAL SELECTION ON PREDATOR/PREY POPULATIONS

PROBLEM? WHAT IS THE IMPACT OF AN ADEQUATE FOOD SUPPLY (THUS RESULTING IN SUCCESS) FOR A PREDATOR POPULATION?

INTRODUCTION

PROCEDURE 1. WORKING PAIRS, CHOOSE A BACKGROUND DESIGN AS YOUR “HABITAT” AREA. 2. SELECT 5 DIFFERENT COLORS OF DOTS; 10 OF EACH OF COLOR. 3. ONE STUDENT (#1) SCATTER THE DOTS ONTO THE BACKGROUND PAPER, WHILE THE OTHER STUDENT (#2) LOOKS AWAY. 4. TO BEGIN, STUDENT #2 WILL THEN TURN AROUND TO “FEED” (PICK UP DOTS) WITH ONLY THEIR INDEX FINGER FOR 30 SEC. 5. RECORD DATA FOR 5 GENERATIONS (“FEEDINGS”). 6. AFTER EACH “FEEDING,” REPLACE ONE DOT FOR EVERY 2 LEFT ON PAPER.

MULTIPLE HYPOTHESIS? IF A COLORED BACKGROUND (“HABITAT”) IS USED FOR DOTS (“PREY”), THEN THE PREDATOR….

VARIABLES?

DATA TABLE (“PREY”) COLOR USED GEN. 1 DOTS PRESENT DOTS LEFT AFTER FEEDING GEN. 2 DOTS PRESENT DOTS LEFT AFTER FEEDING

DATA TABLE (“PREDATOR”) COLORS USED TOTAL G1 DOTS EATEN G2 DOTS EATEN G3 DOTS EATEN G4 DOTS EATEN G5 DOTS EATEN

GRAPHS #1: DOTS (“PREY”) LEFT FOR EACH GENERATION (ALL 5 COLORS ON ONE GRAPH!). #2: DOTS (“PREY”) CONSUMED OVER EACH OF THE 5 GENERATIONS (GRAPH THE TOTAL, NOT INDIVIDUAL COLORS!) * NOTE THE BACKGROUND DESIGN USED !!

QUESTIONS 1. WHAT HAPPENED TO THE PREY POPULATION OVER THE 5 GENERATIONS? WHY? 2. WHAT HAPPENED TO THE “FEEDING SUCCESS” OF THE PREDATOR OVER THE 5 GENERATIONS? WHAT WILL BE THE EFFECT ON THE PREDATOR BECAUSE OF THIS? 3. IN TERMS OF NATURAL SELECTION, WHAT EFFECT HAS THE PREDATOR ON THE PREY POPULATION?