Joshua Joseph

Document Type

Honors Thesis


Large organismal size allows for fish to act in a mobile, predatory manner by opening them up to the possibility of foraging in distinct trophic levels. This may allow for ecosystem stabilization. However, the environmental pressures that select for large and mobile organisms to act in this way have not been identified. Given that this is most likely a behavioral trait, it has been hypothesized that an increased cognitive ability, marked by a larger brain size, would be required by predators to occupy the upper trophic levels of ecosystems. By expanding on food web theory through microscopic analysis, it has been found that fish brain size positively correlates with an increased ability to forage across trophic positions in a food web; thereby indicating that larger brains allow for enhanced cognitive capacity to exploit new feeding niches.

Publication Date






To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.