Abstract
Adaptation to the local environment is crucial for organisms to survive and reproduce in the natural niche. The nematode Caenorhabditis briggsae has been studied extensively and hypothesized to be adapted to temperatures at the geographic sites where nematodes were isolated from nature. We empirically tested if this correlation is biologically meaningful by measuring the fitness of C. briggsae wild strains isolated from different temperatures across the Hawaiian islands. We did not observe a correlation between lifetime fecundity and the temperature of the natural niche from where the strains were isolated, indicating that this fitness trait might not be adapted to local environmental temperatures.