In a polygynous hummingbird species, males defend and monopolize nectar–rich plants (resource). Females visit these plants for nectar and the defending male will have access to all visiting females for mating. Under which scenario is polygyny expected to be the highest?
Show Hint
In logistic growth, per-capita rate \(r(1-N/K)\) peaks at \textbf{low \(N\)} (early phase), while total growth \(rN(1-N/K)\) peaks at \(\mathbf{N=K/2}\) (mid-slope).
Step 1: Identify the mating system mechanism.
This is resource–defense polygyny: a male that can \emph{defend a rich patch} gains access to multiple females attracted to the resource.
Step 2: Ask when a male can best monopolize females.
Two conditions maximize monopolization:
High resource value \(\Rightarrow\) many females aggregate.
Clumped distribution \(\Rightarrow\) defendable by a single male (limited boundary).
Step 3: Evaluate scenarios.
Abundant \& evenly distributed — females spread out; hard to monopolize \(\Rightarrow\) low polygyny.
Abundant \& clumped — females aggregate at defendable patches \(\Rightarrow\) highest polygyny.
Scarce \& even/random — few visits; low male payoff \(\Rightarrow\) low polygyny.
Final Answer:
\[
\boxed{\text{(B) Resources are abundant and clumped}}
\]
