Coen P.H. Elemans
Institute of Biology, University of Southern Denmark
Physical mechanisms for making sound
We found that birds make sound using the same physical mechanisms as mammals do. In songbirds we have a much more detailed understanding how neurons in the brain contribute to song compared to human, but we didn't know how sound was produced and still don't know much about how sound is actually controlled. Our finding allows us to tap into over 60 years of knowledge on the human voice to jumpstart our understanding of sound production and control in birds.
We discovered that mice make their ultrasonic courtship songs by tiny whistles in their larynx, a mechanism that has only been observed by supersonic jet engines. It is important to understand how mice make their ultrasonic love songs because they are a vital tool for linking gene mutations to behavior in mouse models of communication disorders, such as autism.
How do you make sound with a larynx when you return to water and have no airflow available? We discovered that the fully aquatic African clawed frogs evolved a novel mechanism of sound production using a heavily modified larynx.
Superfast motor control of sound production
Superfast muscles are the fastest synchronous vertebrate muscles known and due to their extreme performance have provided valuable insights in basic muscle cell functions, such as rate-limiting steps during excitation-contraction coupling. The phenotype was thought to be extremely rare, but work from our lab has showed it to be ubiquitous in vocal control in birds and mammals and crucial for their communication and survival. In 2017 we showed that SFM operate at a maximum operational speed set by fundamental constraints in synchronous muscle. These constraints set a fundamental limit to the maximum speed of fine motor control.