Opportunities
Postdoctoral research
Contact me for details.
Masters students
I am currently accepting applications. If you are interested, send me your CV or resume, a cover letter, transcripts (unofficial ones are OK), and subject and general GRE scores. There are opportunities to work in either the pollination or Pierce's disease system, or in a different system of your choosing. Some possible projects include research on conservation biology, landscape ecology, ecosystem services, animal behavior, urban ecology, and the functional importance of biodiversity. The graduate student agreement template describes expectations for graduate students in the Greenleaf lab; this agreement is modified for each student's particular situation at the start of his/her degree program.
Undergraduate students
I am currently accepting applications. If you are interested, send me a brief statement of what you are interested in and why you want to do research as an undergraduate. There are opportunities to work in either the pollination or Pierce's disease system, or in a different system of your choosing. Some possible projects include research on conservation biology, landscape ecology, ecosystem services, animal behavior, urban ecology, and the functional importance of biodiversity.
All material on this page, including photos are copyrighted by Sarah Greenleaf. Do not reproduce photos or text without permission.
Pollination Services
Animal pollinators are required to produce about one in every three bites of food that we eat.
Honey bees are the most common crop pollinator species worldwide, but there are another 20,000+ species of bees that are not honey bees. Wild, native bees such as carpenter bees, bumble bees, leaf cutter bees, and mason bees all contribute substantially to the pollination of wild and agricultural plants.
In my research on bees and pollination, some of my goals are to determine the importance of bee pollinators, how they are affected by anthropogenic activities, and what measures can be taken to ensure adquate pollination services in the future.
For more information, see publications on a conceptual model of pollination services, bee foraging, sunflower and tomato. Also, see news reports in National Public Radio, Capital Public Radio, The Scientist, Conservation, Berkeley News, UC Davis News, Fox News, Live Science, and Living on Earth.
Research Overview
We live in a world of rapid environmental change. The sixth major extinction event is ongoing. One-quarter of terrestrial land has been converted to agriculture. All parts of the biosphere have been affected by human activities. What are the consequences of these changes for the maintenance of biodiversity, the continued functioning of ecosystems, and human well-being? This is the question driving my research on ecosystem services.
Disease regulation
Ecosystems provide us with an important service--the regulation of diseases that afflict people, animals, and plants.
Pierce's disease is lethal to grapeplants. It is caused by a bacterium, Xylella fastidiosa, that is vectored by xylem-feeding insects such as the blue-green sharpshooter. Pierce's disease has no cure and costs growers > $9 million per year in northern California.
The landscape-level features that result in Pierce's disease hotspots are complicated and have not been extensively studied. It is also not known how human activities at both the farm and landscape scales affect Pierce's disease.
My research shows that Pierce's disease is most common in vineyards near riparian woodland but only in deforested landscapes. Thus, at the landscape scale natural habitat appears to protect vineyards from Pierce's disease but at the farm scale small patches of riparian woodland are a Pierce's disease source. My ongoing research is determining the biological mechanism(s) that cause this spatial pattern.
