Question

An investigator is interested in how baby snakes find the dens in which they over-winter (termed “hibernacula”). He postulates that the snakes “scent trail” which is to say they follow the scents of other snakes to the den. To test if this is true or not, he sets up a Y shaped maze. He releases an adult snake at the base of the “Y” in the maze and notes whether it took the left or right branch when the path splits. He then releases a baby snake into the same maze and scores how often the baby snake takes the same branch as the adult. After one replicate is run, the brown paper lining the maze is removed to eliminate the old scent trail, and the experiment is re-run. Of 100 separate runs of the experiment 57 baby snakes were found to have taken the same path as the adult, whereas 43 snakes chose the alternate path.   

a. If the snakes are NOT scent trailing what proportion would be expected to go the same way as the adult?

b. Test the null hypothesis (snakes are not scent trailing).  What do you conclude?  Please be sure to show your work as well as summarizing your results (value of Chi square calculated, degrees of Freedom, p value) in the space below

Answer 1