Question

QUESTION 10

After mating, male ladybird beetles offer their mate a “spermataphore” – an energy-rich packet full of proteins for her to consume. For females, the spermataphore provides:

c. Good genes

b. A direct benefit

a. Information on the parasite load of her mate

e. Nothing

d. Assurance that she will have attractive sons

QUESTION 11

You are studying the evolution of colour patterns in guppies (Poecilia reticulata, small tropical fish) and you want to understand the evolutionary mechanisms that drive the evolution of this trait. You make the following observations. First, males vary greatly in coloration, with some individuals having more colour spots than others. Second, more colourful males (i.e. those with more colour spots) have fewer parasites. Third, females strongly prefer to mate with more colourful males. Based on these three observations specifically, you could conclude that female choice in this system is based on:

b. Direct benefit

c. Good genes

e. Females are not choosy

d. Runaway sexual selection

a. The healthy mate theory

Answer 1

1. Assurance that she will have attractive sons

During copulation, male beetles transfer ejaculate via a spermatophore. Females eject and then ingest the emptied spermatophore capsule after copulation; notably, this ingestion causes an acceleration of egg production and a marked increase in female resistance to subsequent matings .

2. The healthy mate theory

Female guppies (Poecilia reticulata) generally show a preference for males with larger, more chromatic orange spots. It has been proposed that this preference originated because it enabled females to obtain high-quality mates. Females select mates with certain traits, because they want their children to be healthy, viable, and reproductively successful.