4step 4.46 Toucan's Beak. The toco toucan, the largest member of the toucan KIN ()) Aa -2. family, possesses the largest beak relative to body size of all birds. This exaggerated feature has received various interpretations, such as being a refined adaptation for feeding. However, the large surface area may also be an important mechanism for radiating heat (and hence cooling the bird) as outdoor temperature increases. Here are data for beak heat loss, as a percentage of total body heat loss, at various temperatures in degrees Celsius:25 LILI TOUCAN Temperature ( C) 15 16 17 18 19 20 21 22 Percentage heat loss from beak 32 34 35 33 37 46 55 51 Temperature ( * C) 23 24 25 26 27 28 29 30 Percentage heat loss from beak 43 52 45 53 58 60 62 62 [1 terstock 4.1 Explanatory and Response Variables 4.3 Interpreting Scatterplots > 5 Er TX