COLUMBIA — Famous romance movies teach boys that singing to girls will win their hearts, but humans aren't the only species that sing for love.
The deafening chorus heard throughout Columbia is the result of hundreds of thousands of male periodical cicadas trying to serenade the perfect mate.
More than 200 people filled the Monsanto Auditorium in the Bond Life Sciences Center at MU on Saturday morning, some of whom sat in the aisles. David Marshall, a researcher at the University of Connecticut, spoke about the unique sounds created by periodical cicadas and their mating process at Saturday Morning Science.
The male cicadas are the singers. They fly around trees, calling out a "love song" in search of a female mate. They make the sound through their tymbals, a region of the cicada’s body where vibrating membranes create the loud humming noise. The full chorus comes together when large groups of males call for mates simultaneously.
While the males provide the vocals, the females set the rhythm.
Female cicadas stay in one place for most of their adult lives. They wait in trees while the males frantically and loudly try to win their approval.
When the right bug comes along, the female flicks her wings, which makes a clicking sound. It's a subtle visual and auditory signal that she's ready to mate.
“The wing flick’s precise timing contains species-specific information that the male listens for, and looks for, and identifies in the chorus,” Marshall said.
The female’s timed response gets the attention of the male and then the courtship process begins.
“Knowledge of the timing and nature of the female reply allows us to develop and test ideas about exactly why the songs are structured the way they are,” Marshall said.
Competition among male cicadas is intense. They only have a few weeks to find a mate and reproduce before they die.
The male cicada doesn't take rejection easily. If he finds a female, but she is unwilling to mate, he might sit near her and make noises to interrupt the song of other males so she doesn't respond to them. A male may do this for hours until the female settles for him, Marshall said.
After mating, the female lays hundreds of eggs into branches. Once the eggs hatch, the cicada nymphs fall directly onto the ground where they feed on plant roots underground for the next 13 years, meaning the cicadas born this summer won't resurface in Columbia until 2024.
Marshall’s presentation kicked off the Invertebrate Sound and Vibration Conference taking place in at the Life Sciences Center until Tuesday. The attending scientists plan to discuss how invertebrates, like cicadas, communicate with each other.
As the audience filtered out after the presentation, newly learned information about cicadas seemed to be the topic of every conversation.
“I thought the lecture was great. I learned a ton,” MU English professor Johanna Kramer said. "You never know what you're going to learn until you listen."
After the lecture, Columbia resident John Clark stopped underneath a tree on the way to his car. Mimicking a BBC video shown during Marshall's lecture, he began snapping his fingers at the cicadas in an effort to reproduce the clicking sounds of females to see if he could get their attention.
“It’s just fascinating,” Clark said. “I can do my own little experiments now!”