Question

A lizard species has males that produce different colour patterns based upon what the juvenile males experience early in life. The juveniles will become colourful adults if they encounter (i) lots of competing males or (ii) few females. Which of the following is MOST LIKELY to be part of that story?

A. The less colourful males have evolved less of the pigment producing genes.
B. Testosterone synthesis is induced in colourful males in response to male-male conflict or female pheromones, activating expression of genes encoding pigment-producing enzymes.
C. Colourful males have evolved a more robust immune system and are less prone to bacterial infections than are the other males.
D. The more colourful males have evolved duplicates of the pigment producing genes.

Answer 1

Orange, blue, and yellow males of side-blotched lizards go through population cycles based on dominance, with different colors being selected depending on the current population makeup.

Step-by-step explanation:

In this scenario, orange males will be favored by natural selection when the population is dominated by blue males, blue males will thrive when the population is mostly yellow males, and yellow males will be selected for when orange males are the most populous. As a result, populations of side-blotched lizards cycle in the distribution of these phenotypes in one generation, orange might be predominant, and then yellow males will begin to rise in frequency. Once yellow males make up a majority of the population, blue males will be selected for. Finally, when blue males become common, orange males will once again be favored.