Mr. Fingers is a gray treefrog. The calling of tree frogs is an announcement that summer has come to Missouri. The sounds of treefrogs fill summer nights.
Amphibians were the first vertebrates to develop a voice. Both frogs and toads call with their mouths tightly shut, but none so enthusiastically as the ambitious treefrog.
Treefrogs have sticky toe pads, called adhesive disks, which enable them to climb trees. They can also cling to glass and other smooth surfaces, often showing up on patio windows or sliding glass doors.