Undergraduate Honors Theses

Thesis Defended

Spring 2015

Document Type


Type of Thesis

Departmental Honors


Environmental Studies

First Advisor

Alex Cruz

Second Advisor

Dale Miller

Third Advisor

Valerie McKenzie


The Rift Valley is a tropical region of eastern Africa characterized by its complex geological makeup consisting of tectonic plates that have driven the formation of some of the largest lakes in the world being Lake Malawi, Victoria, and Tanganyika. In turn, the formation of these amazing freshwater ecosystems has enabled the evolution, and radiation of thousands of species of fish from the family Cichlidae, which constitutes the most diverse group of vertebrates on the globe. However, because these ecosystems are also in regions with a high prevalence of anthropogenic activities they are threatened by biodiversity loss. In particular, Lake Malawi is a notable example as it is an extremely delicate ecosystem that is home to the greatest number and diversity of African cichlids while also being surrounded by countries with severe anthropogenic pressures associated with climate change and increased agricultural activity. With that being said, by conducting an extensive literature review and experimental data collection in the Cruz Lab this study looked at the potential impacts of ecosystem degradation on the reproductive biology and behavior of Malawian cichlids. In doing so, I found that ecosystem degradation could have a negative impact on the reproductive biology and behavior of Malawian cichlids by disrupting aspects of sexual selection, courtship, spawning, and juvenile development and rearing. These finding are significant as they imply that continued ecosystem degradation in Lake Malawi could lead to a reduction in the fitness of Malawian cichlids that could substantially reduce the size and diversity of the largest family of vertebrates in the world.