When One Sex Prevails

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When One Sex Prevails

Scientists have discovered that, during the incubation stage of alligator eggs, a temperature difference in the nest is what determines whether the hatchling will be a male or a female. If the eggs are kept at about 80 degrees Fahrenheit the offspring will be female; if the eggs are kept at 86 degrees Fahrenheit the hatchlings will be male. Since the alligator female is able to control the temperature of the nest in various ways, she is really determining the gender of the offspring.

No scientist believes the mother knowingly prefers male or female offspring. How warm she keeps the nest depends upon many variables: climatic conditions during incubation, the amount and kind of material used to warm her nest, how heavily she piles it on, and so forth.

Many scientists believe this discovery about gender selection in alligators may help us understand the disappearance of the dinosaurs. During the close of the age of dinosaurs, the Mesozoic, the earth was very active tectonically. Mountains were being uplifted, and new ranges, such as the Ancestral Rockies, were coming into existence. This had a profound influence on the world climates. Those climatic changes could have caused one sex of dinosaurs to dominate over the other. This would certainly disrupt reproductive patterns and result in mass extinction.

From the book: 
Petrified Lightning