population size and animal behavior

ECOL302 Lab Handout Unit 7: Behavior

LAB FORMAT: This lab will use an online simulation, similar to the mouse color evolution lab.

BACKGROUND: An organism responds to their environment to decide how they spend their time and energy (behavior), ideally optimizing their fitness payoffs given the costs and benefits of the environment. Together the environment and the behavioral responses will determine the amount of resources the organism can acquire and how much fitness it can gain in a particular habitat. Individual fitness will in turn affect how large the population is. In ecological studies of population size and animal behavior, we are often trying to quantify the connections between environment, behavioral strategies, fitness, and abundance in an environment.

OBJECTIVE: In this lab you will quantify behavioral strategies under different environments, and generate hypotheses for how behavior is optimized given different costs and benefits. In this simulation, you will control the behavior of two honey bees, who are collecting nectar from multiple flowers. The spacing and nectar availability of the flowers (i.e. aspects of the environment for the honey bees) change the payoff for the bees given their foraging effort.

SIMULATION INSTRUCTIONS

● Go to the Virtual Biology Lab for Behavioral Ecology http://virtualbiologylab.org/behavioral-ecology/

● Scroll down to “Model 1 – Honeybee Foraging” and click on the link to review the ‘Directions – PDF’

SIM PART I: Optimize the payoff Click Launch Model (make sure you have the Java extension enabled on your computer!)

1. Start with the default settings for the flowers (Flower-Dist=21; Nectar-Amt=50; Extraction-Rate = 0.06)

2. In your notebook: Record your settings and prepare a table to record values for three things: Forage Time, Nectar Collected, and Collection Rate

3. Set the Forage-Time for each of the bees to two different settings (OK to start with defaults) 4. Click ‘Get Set!’ to prepare the model to run with your parameters 5. Click ‘Go!’ to run the simulation

6. Q1 (1pt). Record in your notebook the Nectar Collected and Collection Rate result for each bee.* Notice that a star appears next to the bee with the higher rate. *NOTE: this model has no random variation in it, so you will get the same result for a bee with the same settings. Bee 1 and Bee 2 differ only in that they give you two opportunities to try different settings at the same time.

ECOL302 Lab – Behavior 1 of 2

 

 

7. Q2 (1pt). Record in your notebook: Change the Forage-Time settings for the two bees to find the setting that gives the highest Collection Rate. (Be sure to use ‘Get Set!’ each time) Show all of your different settings and results.

8. Q3 (2pts). In your notebook: Make a plot of Collection Rate (dependent variable, y axis) vs. Forage-Time (independent variable, x axis) to show where the highest value is found. Be sure to label your axes.

9. Q4 (1pt). Record in your notebook: You have just optimized the payoff for the bees. What is the cost to the bees in this simulation and what is the benefit?

10. Q5 (1pt). Record in your notebook: Was the best Collection Rate also the Forage-Time with the most nectar collected? Explain a situation where it would be better to have a higher rate than a higher total nectar.

SIM PART II: Change the environment 1. Q6 (2 pts). Record in your notebook: Drop Flower-Dist to 5 and find and record the maximum

Collection Rate in the same way that you did above.

2. Q7 (1pt). Record in your notebook: How might having a resource (like flowers) closer together lead to a larger population size?

3. Q8 (1pt). Record in your notebook: How would you design an experiment to test one hypothesis about how the environment would affect the Collection Rate of bees? State the hypothesis, treatment(s), unit of replication, measurement (dependent variable), and prediction.

ECOL302 Lab – Behavior 2 of 2