Modernizing the transeau microslide collection of filamentous conjugating green algae

The National Science Foundation Division of Biological Infrastructure awarded the Academy of Natural Sciences of Philadelphia $185,874 on August 1, 2026, under the Biological Sciences program (CFDA 47.074) to conserve and modernize the Transeau microslide collection of filamentous conjugating green algae.

The project stabilizes more than 1,200 preserved microscope slides containing specimens of conjugating green algae by transferring them into a modern, readily accessible storage cabinet at the Academy's herbarium in Philadelphia. Slide contents will be digitized using a customized microscopy system to capture whole-slide images, which will be published online through the Algal Herbarium Portal of Symbiota, a consortium of research portals for natural history collections. The digitized collection will be accessible to researchers, educators, and the public nationally and internationally. Performance of work occurs in Philadelphia, Pennsylvania, with a period of performance from August 1, 2026, through July 31, 2028. No sub-recipients are planned for this award. The project aligns with the NSF's biotechnology priority area.

Abstract

This project conserves and modernizes a natural history collection of more than 1,200 microscope slides containing preserved specimens of conjugating green algae by improving storage conditions and digitization. These algae are green filaments, or chains of cylindrical cells, that are found in almost every freshwater habitat worldwide and play an important role in aquatic ecosystems. They also exhibit key biological features that were passed down to their evolutionary descendants, the first green plants that spread across dry land 470 million years ago. The unique features of the algae in the collection make the collection an important resource for our understanding of the structure and function of algae and algal adaptations that led to the emergence of plants on land. At present, the collection is difficult to access because the glass slides are fragile and few images or records are available online. This project addresses this issue by stabilizing the slides in a modern, readily accessible storage cabinet in the academy of natural sciences of drexel university herbarium. Slide contents will also be photographed using a customized microscopy system to capture whole-slide images of the specimens. The microscopy process will capture key features of the specimens in digitized images, which will be published online through the algal herbarium portal of symbiota, a consortium of research portals for natural history collections widely used by researchers, educators, and the public. The project makes data and photographs available online to a national and international audience. This project aligns with the NSF?S biotechnology priority area. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the foundation's intellectual merit and broader impacts review criteria.- subawards are not planned for this award.