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Male or Female Alligator


The two graphs below represent the relationship between temperature and the gender of reptile offspring.

The environmental temperature affects the embryonic development after the midpoint of incubation; this time is a temperature sensitive period when the gender is determined and is irreversible.

The Pattern I graph represents some turtle species, and the Pattern II graph represents alligators. You are an alligator breeder and you want to produce more male alligator offspring than female alligator offspring.

Which of the following temperature ranges would be optimal to produce male alligator offspring if the temperature range of the Pattern I graph is 42°C to 62°C,​ and the temperature range of the Pattern II graph is 22°C to 42°C?

Patterns of Temperature-Dependent Sex-Determination in reptiles. Digital image. Wikimedia Commons. Wikimedia Foundation, Inc., 13 Sep. 2014. Web. 16 Dec. 2016.


30°C to 34°C.


22°C to 25°C.


39°C to 42°C.


50°C to 54°C.