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Xs and Os: The Tic-Tac-Toe of Sex Determination


A jigsaw format activity to explore the sex determination mechanisms of seven organisms.

In this structured-inquiry activity, teams of students evaluate the evidence for how sex is determined in a variety of creatures ranging from a freshwater Amazonian turtle to an invasive North American weed and the common house mouse. Like scientists, they must devise hypotheses to account for the available evidence and share their findings with their peers.

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