This passage was adapted from
Nile Crocodiles: Temperature Dependent Sex Determination. <http://www.pulseplanet.com/archive/Feb00/2075.php>
Retrieved February, 2000.
Believe it or not, the sex of baby crocodiles is determined
by the temperature of the eggs when they are in the nest – it's called temperature-dependent
sex determination.
Temperature-dependent sex determination or what is also known
as TSD is a phenomenon that has been studied in a number of reptilian species. And what
this means is that the sex of the hatchling is not determined genetically,
as it is with human beings and with a lot of other mammalian species, but it is actually
determined by the average incubation temperature during the middle
third of the developmental period.
Dr. Alison Leslie is a physiological ecologist with the University of Stellenbosch in South
Africa. She's spent the last four years studying the Nile crocodile in South Africa's Lake
St. Lucia. Dr. Leslie has observed that St. Lucia's crocodiles exhibit an unusual form of
TSD. According to Dr. Leslie, male crocodiles are produced only in temperatures
between 31.7 and 34.5 degrees Celsius. Temperatures below 31.7 or above 34.5 degrees Celsius
produce female hatchlings.
Based on the above passage, what inference can you make about
the future of the Nile crocodile if global warming continues to raise temperatures?
Answer the question here
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