Question

Epinephelus tauvina sex reversal begins at the age of

• A. 2nd year
• B. 3rd year
• C. 4th year
• D. 6th year

Hint:

Groupers = Protogynous (Female to Male). This is the opposite of Anemonefish (Protandrous). Memory trick: Groupers are Gynous first.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The question identifies the age at which the Greasy Grouper (Epinephelus tauvina) begins the process of natural sex reversal.
Detailed Explanation:

• Protogynous Hermaphroditism: Most groupers, including Epinephelus tauvina, are protogynous hermaphrodites. This means they mature and function as females first and later change their sex to become males.

• Timing of Reversal: Research on the reproductive biology of E. tauvina indicates that they reach sexual maturity as females at around 2 to 3 years of age. The transition to the male phase (sex reversal) typically begins as they get older and larger, generally starting from the 4th year onwards.

• Biological Significance: This strategy ensures that larger, older individuals function as males, which might be an advantage in territorial defense and mating. For aquaculture, this is a challenge because it is difficult to maintain large, old males for breeding purposes.

• Artificial Induction: In hatcheries, scientists often use 17$\alpha$-methyltestosterone to induce this sex reversal earlier to obtain functional males for breeding.

Step 2: Final Answer:
Natural sex reversal in Epinephelus tauvina typically begins at the age of 4 years.