There are a few cicadas that can be heard buzzing out at the arboretum. Their sound evokes the long, sun-drenched days of summertime, in which, you want to while away the hot afternoons lounging in the shade by the river.
I found this small explanation on Britannica’s website about their sound: “Cicadas are able to produce these sounds because they possess an organ that is almost unique among insects, the tymbal organ. Each male cicada has a pair of these circular ridged membranes on the back and side surface of the first abdominal segment. Contraction of a tymbal muscle attached to the membrane causes it to bend, producing a clicking sound. The tymbal springs back when the muscle is relaxed. The frequency of the contractions of the tymbal muscle range from 120 to 480 times a second, which is fast enough to make it sound continuous to the human ear. Cicadas also have air sacs that have resonant frequencies comparable to tymbal vibration frequencies, thus amplifying the sound and producing that crescendo of high-pitched buzzing that is the characteristic sound of late summer.”
