The Evolution of Acoustic Signals in Poison Dart Frogs

By: Lia Casey, Jenna Cuzziere, and Rofail Wassef (Stonehill College, BIO 323: Evolution, Spring 2024)

Overview

Poison dart frogs, belonging to the Dendrobatidae family, are a fascinating group of amphibians renowned for their vibrant colors and potent toxins. These frogs are native to the tropical rainforests of Central and South America, where they inhabit diverse habitats ranging from leaf litter on the forest floor to the canopy of trees. Their striking hues, which include shades of red, blue, yellow, orange, and green, serve as a warning to potential predators of their toxic nature. Along with changing colors, poison dart frogs also can utilize acoustic signals (noises animals produce) to attract potential mates. Despite their small size, these frogs can produce a wide array of calls, ranging from simple chirps to complex series of notes. Male poison dart frogs often use their calls to establish and defend territories, as well as to attract mates during the breeding season. Each species has its unique call, which helps in species recognition and mate selection. Additionally, acoustic signals may also serve as a form of communication between males and females during courtship rituals, or mate selection, aiding in the coordination of reproductive behaviors. The frequency, duration, and intensity of these calls can convey information about the caller’s size, health, and vigor, influencing the outcome of mating interactions. Furthermore, studies have shown that environmental factors such as temperature and humidity can impact the acoustic properties of these calls, highlighting the intricate interplay between biology and the environment in the vocal behavior of poison dart frogs. Feel free to tune into the podcast to learn more about this exciting topic!

Short podcast summarizing the paper. Image of a Poison dart frog. Acoustic signals in poison dart frogs serve as vital communication tools for territorial defense, mate attraction, and courtship rituals within their diverse rainforest habitats. https://www.britannica.com/science/animal-communication/Signal-production
Podcast Music: https://www.youtube.com/watch?v=498HcLwcjxs
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Tadpole Adaptations to Increasing Temperatures in Urban Environments

By: Mallory Crispens, Sarah Faley, and Lilly Leach (Stonehill College, Bio323: Evolution Spring 2024)

Overview

One of the most beneficial characteristics for survival in the natural world is the ability to adapt to changing environments. In the face of climate change and increasing urbanization of rural areas, it has become even more important for wildlife to be able to adapt and endure increasing temperatures. Urban heat islands are a significant consequence of urbanization, occurring when cities replace natural land cover with dense concentrations of pavement, buildings, and other surfaces that absorb and retain heat. These heat islands create a brand-new environment for wildlife, particularly for pond-dwelling animals such as tadpoles whose aquatic environment is sensitive to change. While most organisms living in urban environments have elevated tolerance to heat, the thermal adaptations of aquatic organisms are relatively unknown. In the article, “Tadpoles Develop Elevated Heat Tolerances in Urban Heat Islands Regardless of Sex”, Dr. Bokony analyzes tolerance to increasing temperature, as a result of urbanization, in tadpoles.

A short podcast summarizing the article. Soundtrack image from https://scx2.b-cdn.net/gfx/news/2017/tadpole.jpg
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The Benefits of Commitment in Black-headed Gulls

By: Karina Rodrigues, Joanna Soliman, Yenifer Oseguera, and Giana Youssef (Stonehill College, BIO323: Evolution, Spring 2023)

Overview

Loyalty, a quality some lack and some do not. Have you ever thought about the positive effects loyalty has on people, better yet species? In terms of evolution, loyalty translates to how committed a species is to its breeding partner. Originating from the Netherlands, black-headed gulls (Chroicocephalus ridibundus) were used to study the benefits of long-term relationships and if it plays a role in how parents invest more with their partners as well as their pair bond with one another. These seabirds were studied in a model environment that fits the birds natural needs in order to exhibit their natural behaviors. After testing different mechanisms, selection for mate retention reduces parental care conflicts between a pair and also sheds light to selecting traits that increase individuals fitness throughout evolution.

A short podcast summarizing the article.
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Parallel Evolution of Avoidance Behaviors Exhibited by Freshwater and Marine Sticklebacks

By: Moussa Abboud, Victoria Pinaretta, Jack Ryan, and Cameron Sarkisian (Stonehill College, BIO323: Evolution, Spring 2023)

Just as natural selection acts on land, the creatures of the sea experience the same selective pressures! As a mode of evolution, natural selection works by weeding out those who are not as fit as others, while promoting those who are most successful at survival and reproduction. If the history of evolution has taught us anything, it is that one important way to make sure your genes get passed on through your offspring is to become the best at adapting to your environment! A great example of such a concept is visualized in nine-spined sticklebacks (Pungitius pungitius), where the predatory avoidance behaviors of freshwater and marine populations provide insight into the differences in how they evolved this behavior from a common ancestor. Here, we summarize an article about these sticklebacks that was published recently in Evolution by researchers from the University of Helsinki.

A short podcast summarizing the article
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