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
Continue reading “The Evolution of Acoustic Signals in Poison Dart Frogs”

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
Continue reading “Tadpole Adaptations to Increasing Temperatures in Urban Environments”

The Cost of Reproductive Investment on Canine Life Span

By: Jentry Allen, Isabella Caldarone, Jacqueline Foley, and Nicole Godbout (Stonehill College, BIO323: Evolution, Spring 2023)

Overview
Dogs are said to be a man’s best friend as they are wonderful companions and can be trusted like no other pet; they are loyal to a fault. We find comfort in our dogs, maybe even purpose. Some people are willing to put their lives in the hands of dogs, allowing them to be their eyes, tell them if a food contains an allergy that may cost them their life, and inform a person if they are on the brink of an epileptic attack so that they may find a safe space and be prepared. An article from The American Naturalist titled, “High Investment in Reproduction is Associated with Reduced Life Span in Dogs”, discusses research on this ever-reliable friend and pet that shows a pattern in their life span in relation to offspring production. It was found that higher reproductive investment, or the work and energy that goes into reproduction, causes a decrease in canine life span. Additionally, it was discovered that this effect on life span was greater for larger dog breeds. With breeders today who want to breed more and larger puppies, we questioned the possible evolutionary effects of artificial selection, or the act of humans breeding animals to achieve a certain characteristic. If a breeder selects for a larger litter with larger puppies, the reproductive investment will be higher, and in theory, the life span of the mother will be decreased. Hear more about our discussion on this topic on the Everyday Evolution podcast!

A short podcast summarizing the article
Continue reading “The Cost of Reproductive Investment on Canine Life Span”