Digital Commons Network^™

Variation In The Maternal Provisioning Of Alkaloids In The Strawberry Poison Frog Oophaga Pumilio: The Relationship Between Mothers And Their Tadpole Offspring, Olivia L. Brooks

Masters Theses

Within and among populations, alkaloid defenses of strawberry poison frogs (Oophaga pumilio) vary spatially, temporally, and with life history stage. Natural variation in defense has been implicated as a critical factor in determining the level of protection afforded to an individual from predators and pathogens. Oophaga pumilio tadpoles sequester defenses from nutritive eggs and are thus entirely dependent on their mothers for their alkaloids. However, it remains unclear how the alkaloid composition of a tadpole relates to that of its mother and if maternally provisioned defenses are effective against predators. Here, I demonstrate that natural variation in the alkaloid composition …

Behavioural Preference For Low Levels Of Uv-B Radiation In Two Neotropical Frog Species From Costa Rica, Joseph A. Demarchi*, Andrew Britton**, Kaylee O'Donnell**, Ralph Saporito

2018 Faculty Bibliography

Tropical frogs experience damaging effects from exposure to UV-B radiation, and some diurnally active, con- spicuous species exhibit avoidance behaviours to high levels of UV-B. To determine if similar behaviours are present in

other diurnal frogs, we experimentally compared UV-B avoidance in two common species of neotropical diurnal frogs – Oophaga pumilio, an aposematic poison frog and Craugastor bransfordii, a cryptic leaf-litter frog – in response to different levels of UV-B. Wild-caught frogs were tested in experimental arenas fitted with filters that permitted two different levels of UV-B (low: 14% vs. high: 84% UV-B). Both species spent significantly more time …

Geographic Variation In Alkaloid-Based Microbial Defenses Of The Strawberry Poison Frog, Oophaga Pumilio, Annemarie Mina

Senior Honors Projects

Frogs of the family Dendrobatidae use alkaloids as a chemical defense against predators. Alkaloids are not manufactured by frogs, but instead sequestered from a diet of arthropods. Alkaloid defenses in dendrobatids differ with geographic location, mainly because arthropod availability varies with location. It has been postulated that alkaloids also function as a defense against microbes and different frog alkaloids might be more/less effective against microbes. We assessed this hypothesis by testing the effectiveness of alkaloids in the dendrobatid frog Oophaga pumilio from five geographic locations in Costa Rica and Panama against different microbes. Alkaloids were tested against the bacteria Escherichia …