The Pfizer Plant Research Laboratory in The Bronx, built with funding from the National Oceanic and Atmospheric Administration, New York State and New York City, and named for its largest private donor, is a major new research institution at the New York Botanical Garden opened in 2006. The laboratory is a pure research institution, with projects more diverse than research in universities and pharmaceutical companies. The laboratory's research emphasis is on plant genomics, the study of how genes function in plant development. One question scientists hope to answer is Darwin's "abominable mystery"; when, where, and why flowering plants emerged. The laboratory's research also furthers the discipline of molecular systematics, the study of DNA as evidence that can reveal the evolutionary history and relationships of plant species. Staff scientists also study plant use in immigrant communities in New York City and the genetic mechanisms by which neurotoxins are produced in some plants, work that may be related to nerve disease in humans. A staff of 200 trains 42 doctoral students at a time from all over the world; since the 1890s scientists from the New York Botanical Garden have mounted about 2,000 exploratory missions across the planet to collect plants in the wild. At the plant chemistry laboratory chemical compounds from plants are extracted to create a library of the chemistry of the world's plants and stored in a DNA storage room with 20 freezers that store millions of specimens, including rare, endangered or extinct species. To protect them during winter power outages, there is a backup 300-kilowatt electric generator.