Question

Two unique reptilian species(P and Q) reproduce in ambient temperature range(${31}^o$C to ${35}^o$C only). A group of scientists found a strange observation regarding the "male to female ratio" as obtained from fertilized eggs artificially hatched within laboratory incubators, as shown in the figure.
The maximum life span of these reptiles is $5$ years. $50$mole and $50$ female adults each of species P and Q were used to start a $10$ year long study. The eggs were always hatched in incubators during this study. In the absence of any other factors, which of the following possible outcome(s) is/are correct?

• A. If the temperature of the incubator is strictly maintained at ${33}^o$C for $10$consecutive years, the species P is expected to have more males than in species Q
• B. If the temperature of the incubator is strictly maintained at ${31}^o$C for $10$ consecutive years, there will be more males in species P than in species Q
• C. If the temperature of the incubator is strictly maintained at ${31}^o$C for $10$ consecutive years, then both P and Q will not survive in the lab
• D. If the temperature of the incubator is strictly maintained at ${31}^o$C and ${35}^o$C for every alternate year (for a total of $10$ years), there will be more males in species P than species Q

Answer 1

Answer: (A), (C), (D)

The correct options are
A If the temperature of the incubator is strictly maintained at ${33}^o$C for $10$consecutive years, the species P is expected to have more males than in species Q
C If the temperature of the incubator is strictly maintained at ${31}^o$C for $10$ consecutive years, then both P and Q will not survive in the lab
D If the temperature of the incubator is strictly maintained at ${31}^o$C and ${35}^o$C for every alternate year (for a total of $10$ years), there will be more males in species P than species Q

According to the given graphs, it is observed that at 33${}^0$C there are no males produced in species Q and there are 100% of females present. However, at the same temperature, there are 50% male and 50% females present in species P. Hence, if the temperature of the incubator is strictly maintained at 33${}^0$C for 10 consecutive years, the species P is expected to have more males than in species Q. At 31${}^0$C, there are only males present in both species P and Q and no females. If the temperature of the incubator is strictly maintained at 31${}^0$C for 10 consecutive years, then both species P and Q will not survive as there will be no reproduction taking place without females. At 35${}^0$C, there are no males and 100% females in species P. However, at the same temperature, there are 100% males and no females. Hence, if the temperature of the incubator is strictly maintained at 31${}^0$C and 35${}^0$C for every alternate year, there will be more males in species P than species Q because no reproduction will take place in species Q in absence of females.

Thus, options A, C and D are correct.