Male turkeys have a snood, which is a flap of skin that hangs across their beak. Snood length is negatively correlated with parasite load (e. g., males with longer snoods have fewer parasites), and females prefer to mate with long-snooded males. The snood is an example of:

it also supports my hypothesis. if you rest first you can squeeze the clothespin more times. from the data i collected the average of the eight people concluded exercise makes your muscles more fatigued and less able to squeeze the clothespin compared to resting before squeezing.

answer diabetes mellitus;