Ecotourism helps conserve wildlife by increasing the value of wildlife conservation for local people. In Argentina, the world's largest breeding colony of Magellanic penguins is visited by thousands of tourists every year, causing the penguins to become habituated to the presence of people. Has ecotourism affected the penguins' ability to respond to stressors? Has it affected the penguins' secretion of corticosterone? Scientists tested the hypothesis that penguins habituated to tourists have a blunted stress response overall. They examined the corticosterone response of habituated and non-habituated penguins to another stressor—that of being captured and restrained for 30 minutes. They found that both habituated and non-habituated penguins secreted corticosterone in response to being captured and restrained, but that the level of corticosterone after 30 minutes differed between the groups. The results are shown here (* means P<0.05). Was the hypothesis supported? Explain.

Video transcript

Hello, everyone here. We have a question telling us that a researcher proposed the hypothesis that squirrels found in gardens that are habituated to humans have a weakened stress response overall, she tested her hypothesis by subjecting them to a new type of stress, which included capturing and holding the habituated and non habituated squirrels for one hour. She then determined the levels of corticosteroids are in in both groups. If her hypothesis is correct, what should be the correct equation between the cortical steroid levels in the two groups? So we would want the non habituated squirrels to have a greater stress response, which means a greater level of corticosteroid. Um So we would want to be non habituated squirrels greater than habituated squirrels. Thank you for watching. Bye!