Question

Consider a species of brightly colored beetle. Which one or more of the following observations suggest(s) that this species is aposematic?

• A. ( Both male and female beetles are brightly colored. )
• B. ( Only male beetles are brightly colored. )
• C. ( Only female beetles are brightly colored. )
• D. ( The beetle species is toxic and distasteful. )

Hint:

When studying potential aposematic species, look for consistency in warning signals across the population and direct evidence of deterrent traits like toxicity.

Answer 1

The Correct Option is A

Aposematism is a defensive mechanism where organisms use bright coloration to signal toxicity or distastefulness to potential predators. This type of warning signal is generally evolutionary advantageous if it is visible to both sexes, indicating a genetic and phenotypic consistency across the population that aids in predator learning.
Analysis of Each Option: (A) Correct: Bright colors in both male and female beetles suggest that the warning coloration is a species-wide trait, not just limited to one sex, supporting the aposematic function. 
(B) Incorrect: While brightly colored males may suggest sexual selection, it does not necessarily imply aposematism without additional evidence of toxicity. 
(C) Incorrect: Similarly to (B), bright coloration only in females could be due to sexual or selective pressures other than predation. 
(D) Correct: Directly states that the species is toxic and distasteful, which is a hallmark of aposematism. Conclusion:
Explanation: The combination of widespread bright coloration across sexes and direct evidence of chemical defense strongly supports the presence of aposematism in this beetle species. This strategy enhances the survival of the species by deterring potential predators through easily recognized visual cues.