The Plant Press

Abstracts from the speakers of the 19th Smithsonian Botanical Symposium

From Plant Press, Vol. 25, No. 3, July 2022.

The 19^th Smithsonian Botanical Symposium, “Life on the Edge: Exceptional Plants in Exceptional Places,” was held on 13 May 2022. The invited speakers specializing in conservation, ecology, systematics, and genetics explored plant survival in extreme parts of the natural world. Below are the abstracts from the papers that were presented by the invited speakers.

Susan Pell (far left), USBG Deputy Executive Director, and Eric Schuettpelz (far right), Chair of the Botany Department, join the speakers of the 2022 Smithsonian Botanical Symposium at the National Museum of Natural History (from left): Fabián Michelangeli, Ben Nyberg, Jenna Ekwealor, Tanisha Williams, and Jessica Allen. (photo by Ken Wurdack)

Jessica Allen
Eastern Washington University
“Urban Lichens: Symbioses in the built environment”

Densely populated urban areas are centers of exceptional human culture, wealth and political power. The biodiversity that occupies major cities alongside their human inhabitants, while typically not exceptional in their rarity, are exceptional in their adaptability and resilience. Of the biodiversity observed in cities, lichens are some of the most colorful and ubiquitous. These quintessential symbioses are the dominant and most diverse organisms in many of the harshest environments on the planet, yet they are incredibly sensitive to anthropogenic change. In this talk I will discuss how lichens have responded to urbanization in the Northeast Megalopolis over the past two centuries and will compare these patterns to those observed in select cities around the world. I will discuss the lichens of New York City, the heart of the Northeast Megalopolis, in depth, where a documented decline occurred throughout much of the 19^th and 20^th centuries. Since the 1970s there has been a notable rebound in the lichens of New York, and I will introduced you to some of the remarkably resilient city-dwelling species that have managed to grow, and even thrive, in one of the mostly densely urbanized regions on the planet.

Jenna Ekwealor
Smithsonian Institution
“The secret lives of desert moss”

Desert plants experience extreme fluctuations in light, temperature, and water availability. These intense conditions shape the development, life history, and evolutionary trajectory of desert mosses. In this talk, I will present on two such processes: vegetative growth and sexual reproduction. First, I discuss the discovery of Mojave Desert mosses occurring as hypoliths under milky quartz rocks. To characterize this unique moss microhabitat, we deployed microclimate dataloggers and collected samples in a Mojave site containing quartz hypoliths. The results of this study highlight the need to consider microhabitats, especially in extreme environments, where mosses may find refuge from the prevailing macroclimatic conditions. Second, I discuss how natural populations of many desert mosses appear highly female-biased based on the presence of reproductive structures. The dryland moss Syntrichia caninervis is notable for its low frequency of sex expression and strong female bias. Using molecular methods, we uncovered the genetic sex of non-expressing shoots and compared the patterns of phenotypic and genotypic sex ratios in Mojave populations. The findings shared in this talk contribute to our understanding of how the environment may modulate habitat filtering, vegetative growth, and sexual reproduction in S. caninervis, either through its direct influence on physiology or through selection.

Michelangeli receives the 19th Cuatrecasas Medal [Video]

From Plant Press, Vol. 25, No. 3, July 2022.

The José Cuatrecasas Medal for Excellence in Tropical Botany is named in honor of Dr. José Cuatrecasas, a pioneering botanist and taxonomist, who spent nearly a half-century working at the National Museum of Natural History. Cuatrecasas had a distinguished career devoted to systematic botany and plant exploration in tropical South America, especially in the Andes, and this award serves to keep vibrant his accomplishments and memory. The Department of Botany and the U.S. National Herbarium present this award at the Smithsonian Botanical Symposium to a botanist and scholar of international stature who has contributed significantly to advancing the field of tropical botany. The award consists of a bronze medal bearing an image of José Cuatrecasas on the front with the recipient’s name and date of presentation on the back.

This year the 19^th José Cuatrecasas Medal for Excellence in Tropical Botany was presented to Fabián Michelangeli.

Fabián Michelangeli accepts the 19th José Cuatrecasas Medal for Excellence in Tropical Botany. (photo by Ken Wurdack)

Michelangeli earned a Bachelor of Science in Biology in 1993 from the Universidad Central de Venezuela in Caracas and a Ph.D. in 2000 from Cornell University for research on Tococa, a genius of ant plants in Melastomataceae. Since 2004 he has been a curator in the Institute of Systematic Botany at the New York Botanical Garden (NYBG) where he continues his research on Melastomataceae. With about 177 genera and 5,800 species, Melastomataceae is one of the most easily recognized tropical plant families and the Smithsonian and NYBG have some of the world's best collections due to multiple generations of curator research on the family.

An exceptional symposium explores plants on the edge [Video]

From Plant Press, Vol. 25, No. 3, July 2022.

The 19^th Smithsonian Botanical Symposium, co-hosted by the Smithsonian’s Department of Botany and the United States Botanic Garden (USBG), made a welcome return to the National Museum of Natural History’s (NMNH) Baird Auditorium on May 13, 2022, three years after the last time the event was held in person. The Symposium, “Life on the Edge: Exceptional Plants in Exceptional Places,” was a hybrid event, bringing together five engaging speakers to present their research to both in-person and virtual audiences from around the world. The invited speakers included scientists specializing in conservation, ecology, systematics, and genetics whose research explores plant adaptation and survival in extreme parts of the natural world. The speakers talked about their research on plants (and lichens) growing in exceptional environments, from the tepuis of the Guayana Shield and the steep cliffs of Hawaii to the South African Fynbos, the Mojave Desert, and even New York City. They spoke about natural history and evolution, and the challenges plants endure in the face of climate change and increasing pollution.

Susan Pell (far right) moderates a panel discussion with the symposium’s speakers: (from left) Fabián Michelangeli, Tanisha Williams, Jessica Allen, Jenna Ekwealor, and Ben Nyberg. (photo by Ken Wurdack)

Eric Schuettpelz, NMNH Chair of Botany, welcomed the audience to the symposium and Rebecca Johnson, NMNH Associate Director for Science and Chief Scientist, provided opening remarks. In her comments, Johnson talked about a project, “Life on a Sustainable Planet,” currently in development at NMNH, and she tied the project to the theme of the symposium. She described the new project as, “understanding, explaining, and amplifying the reach, relevance, and impact of the work here at the Smithsonian,” and the relevance to the tens of thousands of species 'on the edge'. Susan Pell, USBG Deputy Executive Director, also provided opening remarks and gave an orientation to the USBG, including a description of the living collections, current online and in-person programming, and their scientific and conservation partnerships.