Sexual Selection and Mate Choice
At the end of this lab, students should know...
View the full transcript and gain access to JoVE Lab Manual videos
Q1: How do you determine the number of students needed for a sexual selection mating simulation?
Scale the activity based on class size using provided options for 30, 20, or 10 students. Maintain an equal male-to-female ratio, designate most individuals as average quality, and ensure equal numbers of high- and low-quality individuals. Use an even number of participants; if odd, assign one student to tally matings each round.
Q2: What materials are needed to create information badges for the mating simulation?
Acquire 10 clip-on plastic ID holders and number them one through 10. Mark Q and A in upper and lower corners, then draw dots representing quality and attractiveness values next to each letter. Cover half the holders with white paper strips, add three paper clips to each male holder, and prepare colored paper strips to represent gametes.
Q3: How many gamete strips should each student receive in the mating activity?
Female students receive four pink paper strips each, representing eggs. Male students receive 16 blue paper strips and one white paper strip each, representing sperm and a concealment strip. Number each set of strips with the individual's ID to track reproductive success across mating rounds.
Q4: What is the purpose of the fertilization area in the sexual selection lab?
The fertilization area, positioned away from the mating area, is where students place paired gametes after mating occurs. Paper clips at this station allow students to clip paired gametes together, creating a physical record of successful matings for data collection and analysis.
Q5: How should class data be prepared for student analysis after the mating simulation?
After tallying matings in Spreadsheet 1, copy relevant data as values only into Spreadsheet 2 for student distribution. This prevents students from seeing formulas and focuses their analysis on interpreting results. Formulas for average matings and reproductive success may need adjustment based on actual class size.
Q6: What role does the instructor play during the mating simulation rounds?
The instructor or helper keeps time during each mating round and records which matings occur in the spreadsheet. This real-time data collection ensures accurate tracking of reproductive success and mating patterns, which students later use to create graphs and analyze selection pressures.
Q7: Why is maintaining an equal male-to-female ratio important in the sexual selection simulation?
An equal sex ratio ensures balanced mating opportunities and prevents skewed reproductive success data. This allows students to observe how quality and attractiveness traits influence mate choice without confounding variables from unequal population sex ratios affecting selection outcomes and evolutionary patterns.