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Tree swallows are North American birds that can help us understand more about biology. We already know a lot about tree swallows because they are easy to work with. These birds are popular for scientists to study. We know a lot about bird health, migration, and nesting because of tree swallows. However, tree swallows are declining because of climate change, insect loss, and habitat destruction. You can help by becoming a community scientist! Tree swallows are fascinating birds that everyone can help conserve. And along the way, we can learn more about our world. 

Biodiversity is the word used to describe the rich variety of life on Earth. Right now, Earth’s biodiversity is threatened. Museums, zoos, and other kinds of natural history collections help to protect biodiversity. One way they do this is by helping researchers study life on Earth. Another way is by teaching people, through exhibits and events. Natural history collections face many challenges. One challenge is getting enough money to stay open. Another is finding new space as collections grow. Finally, some people who want to use and learn from collections cannot access them because they are not nearby. Museum collections are now putting information on the internet, so that many people can access and use it. We can all help natural history collections to continue protecting Earth’s biodiversity by visiting them, volunteering, and donating specimens or other resources. 

Abstract Researchers have long examined the structure of animal advertisement signals, but comparatively little is known about how often these signals are repeated and what factors predict variation in signaling rate across species. Here, we focus on acoustic advertisement signals to test the hypothesis that calling males experience a tradeoff between investment in the duration or complexity of individual calls and investment in signaling over long time periods. This hypothesis predicts that the number of signals that a male produces per 24 h will negatively correlate with (1) the duration of sound that is produced in each call (the sum of all pulses) and (2) the number of sound pulses per call. To test this hypothesis, we measured call parameters and the number of calls produced per 24 h in 16 species of sympatric phaneropterine katydids from the Panamanian rainforest. This assemblage also provided us with the opportunity to test a second taxonomically specific hypothesis about signaling rates in taxa such as phaneropterine katydids that transition from advertisement calls to mating duets to facilitate mate localization. To establish duets, male phaneropterine katydids call and females produce a short acoustic reply. These duets facilitate searching by males, females, or both sexes, depending on the species. We test the hypothesis that males invest either in calling or in searching for females. This hypothesis predicts a negative relationship between how often males signal over 24 h and how much males move across the landscape relative to females. For the first hypothesis, there was a strong negative relationship between the number of signals and the duration of sound that is produced in each signal, but we find no relationship between the number of signals produced per 24 h and the number of pulses per signal. This result suggests the presence of cross-taxa tradeoffs that limit signal production and duration, but not the structure of individual signals. These tradeoffs could be driven by energetic limitations, predation pressure, signal efficacy, or other signaling costs. For the second hypothesis, we find a negative relationship between the number of signals produced per day and proportion of the light trap catch that is male, likely reflecting males investing either in calling or in searching. These cross-taxa relationships point to the presence of pervasive trade-offs that fundamentally shape the spatial and temporal dynamics of communication.