The role of plasticity in the evolution of novelty in animal communication

University Of Denver, Denver CO

Investigators

Abstract

Understanding how new traits arise is fundamental to explaining the diversity of life on Earth, but it is challenging to imagine how novel traits could arise in animal communication because communication requires coordination between a sender and a receiver. For example, if a sender evolves a novel signal, it may not be perceived or recognized by the intended receiver as a signal. Yet we know that novel signals do evolve. Plasticity has been suggested as a possible explanation. Plasticity refers to changes in an organism in response to the environment. For example, perhaps exposure to a novel signal plastically changes the preferences of the receiver so that they are willing to accept senders with this signal. In this proposal, the researchers capitalize on the recent discovery of two novel signals (songs) that Pacific field crickets use to attract mates. The researchers propose a large breeding experiment where male and female crickets are exposed to different songs, including the two novel songs, beginning at a young age. Researchers will then measure plasticity in adult crickets for a suite of reproductive traits to uncover the role of plasticity in the origins of novelty. This project also integrates education aims to support young scientists in the LGBTQ+ community, mentoring diverse undergraduate students in independent research, creating teaching resources that use data from this research to teach about plasticity and novelty, and using a web-based citizen science platform to allow the public to participate directly in the research. Novelty is readily detectable on a macroevolutionary scale, and novel traits can drive diversification, but opportunities to observe novelty in real time are rare, so empirical examples and opportunities to ask how novel traits arise are lacking. It is particularly challenging to imagine how novelty could evolve in animal communication because communication requires coordination between a sender and a receiver. It has been suggested that phenotypic plasticity may facilitate the establishment of novel traits, and developmental plasticity has been specifically linked to innovation. Two novel signals (songs) recently evolved in Hawaiian populations of Teleogryllus oceanicus, providing an unprecedented opportunity to test the central hypothesis that plasticity facilitates the establishment of novelty. The researchers propose a large breeding experiment with acoustic rearing treatments to measure plasticity in receivers and senders for suites of reproductive traits in ancestral and derived morphs. The work will reveal whether novelty can evolve in the absence of plasticity or instead if novel communication signals are facilitated by plasticity in receivers, senders, or both. The use of a genotype-by-environment breeding design will also establish whether plasticity pre-dates the origin of novel signal features and at what stages of the reproductive process plasticity overcomes reproductive barriers. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.