Skin biopsy collection
We collected chest skin biopsies from 15 adult males, 15 adult females, 6 subadult males, and 2 subadult females during the annual SMGRP capture-and-release campaigns. Adulthood was determined by the eruption of the third molar which aligned with our phenotypic metrics of adulthood for known individuals (McNamara & Graber, 1975). Biopsies were collected with a 4mm punch biopsy tool, placed vertically over the chest patch skin and pressed and rotated in one direction to move the punch through the skin to the subcutis. The biopsy was then removed, placed in a 1.5 mL microcentrifuge tube with 0.5 mL RNAlater™, and frozen in liquid nitrogen within 6 hours. The resulting small wound was treated with antimicrobial aluminum aerosol bandaging to stop any bleeding and prevent infection. Upon arrival in the laboratory (still frozen in a liquid nitrogen vapor shipper), samples were stored at -80℃ until RNA extraction.