The flexibility of the membranes used for the cymbalization of cicadas is conditioned by the atmospheric temperature. Below 71.6 to 75.2°F (22 to 24°C), depending on the species, they contract and become too rigid to be deformed by the muscles of the abdomen. All the male cicadas then stop singing almost simultaneously to resume in unison in the morning. After more than an hour of intermission, it is common for them to resume singing temporarily in the evening as the earth releases the heat accumulated during the day. Cicadas do not sing when the wind is strong nor in case of danger, when a predator approaches or when someone picks them up for instance.