Jennifer Lee Rose Hills
Understanding Coexistence Of The Hawaiian Tetragnatha Spiders
Understanding niche differentiation is fundamental for comprehending the complicated process of adaptive radiation, characterized by the rapid formation of many ecologically different species from a single ancestor. However, evolutionary biologists still highly debate how niche differentiation is achieved during the early stage of adaptive radiation. On the one hand, through character displacement, natural selection could facilitate differentiation and diversification between closely related species where they co-occur with no need for prior niche differentiation at the time of secondary contact. Alternatively, enough niche differentiation between species can be achieved in isolation before range overlap, facilitating coexistence and reducing the chance for competitive exclusion. Therefore, this project aims to conduct a comparative analysis between sympatric and allopatric populations of the three species of the green ecomorphs of Hawaiian Tetragnatha “spiny-leg” spiders (T. waikamoi, T. brevignatha, & T. macracantha) to answer how these species can coexist with one another based on different dimensions of niches. Using carbon and nitrogen isotopic signatures of the spiders’ tissues and other morphological assessments in sites where the taxa do and do not co-occur will help address this question. Therefore, this study will allow insights into the Hawaiian “spiny-leg” spiders’ diversification patterns and the mechanisms driving adaptive radiation.