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Biologists Rebecca M. Calisi-Rodriguez and George E. Bentley examined research on white-throated sparrows and degus, both of which have been studied in the laboratory as well as in the wild, to see how studies' settings might have affected their results. Lab studies are useful because they make it easy to control important variables, but white-throated sparrows' surroundings can significantly affect their hormone levels. Therefore, it's not altogether surprising that when Calisi-Rodriguez and Bentley examined studies of white-throated sparrows, they found that

hormone levels were higher in wild males than in captive male degus.

captive sparrows and wild sparrows usually exhibited very similar hormone levels.

significant differences in hormone levels between individuals were found for both captive sparrows and wild sparrows.

baseline levels of the hormone corticosterone are higher in captive sparrows than they are in wild sparrows.