Understand Biodiversity

Biodiversity exploration, documentation, and study

Effective plant, lichen, and ecosystem conservation starts with the basics: biodiversity exploration, documentation, and study. At the Garden, our botanists and lichenologist endeavor to better understand California’s rich flora through the application of a wide variety of techniques, from field work to taxonomic study to phylogenomics. All our work contributes to and benefits from the Garden’s natural history collections, which include the Clifton Smith Herbarium, the SBBG Lichen Herbarium, and the new SBBG Fungarium.

Exploring and documenting California’s plant and lichen biodiversity

Image of D. cymosa subsp. agourensis taken by Emily ThomasField work is often a critical first step in our efforts to explore and document California’s biodiversity. Although some portions of California’s majestic Central Coast and the Channel Islands have been well-studied by botanists, there are still significant gaps in our understanding, and locations where no botanist has ever set foot . Our Biodiversity Team observes and studies plants and lichens in nature, making invaluable scientific collections for long-term preservation in our natural history collections, now housed in the new Pritzlaff Conservation Center . Our herbaria are the official repositories of plant and lichen specimens collected on the Channel Islands National Park, and we have the largest collection of Channel Island plant and lichen specimens under one roof. These specimens serve as the foundation of our work to understand the local flora. Our published floristic syntheses include annotated checklists for several of the Channel Islands and a number of books (published or in preparation) focusing on individual islands or the archipelago as a whole. Beyond floristics, our specimens have been used for studies in taxonomy, genetics, phenology, and more.

Detecting and Describing Novel Biodiversity

Image of Chaenotheca longisporaDespite significant study by botanists over the years, there is still much to learn about the California flora and many mysteries yet to be solved. Building on our field observations and careful study of herbarium specimens, Garden botanists endeavor to detect and describe novel plant and lichen biodiversity on the Channel Islands and the California mainland. Detecting and characterizing new species is often done by making comparisons of the potentially new species with its close relatives. These analyses rely on precise measurements taken in the field or back at the Garden in the herbarium or one of our lab spaces (e.g., the Plant Anatomy Lab ). In addition, genetic data are often gathered to complement our studies of plant form. As one recent example of a soon-to-be recognized species, Garden botanists detected a potentially new popcornflower (Plagiobothrys “colonetensis”, Boraginaceae) in the vernal pools of NW Baja California. It seemed to differ from its close North American relatives ecologically and in features of its small fruits, a pattern we assessed using fine-scale measurements from high-resolution microscope images. Another example of a recently described species is Chaenotheca longispora, a tiny so-called pin lichen that grows on trunks of old coast redwood (Sequoia sempervirens, Cupressaceae) trees in Armstrong Redwoods State Natural Reserve. The lichen was observed on the thick, fibrous bark from 9 to 73 m above ground level . Unlike other species in this genus, the spores of C. longispora are ornamented with spiral ridges.

Using the building blocks of life to conserve biodiversity

Image of Emily Thomas in the labIn the SBBG Plant Genetics Lab, we use DNA sequence data as a tool in three broad research themes: population genomics for conservation of rare plants, phylogenetics to understand evolutionary relationships of groups of plants, and DNA barcoding. For example, Island Mallow (Malva assurgentiflora subsp. assurgentiflora, Malvaceae) is a Channel Islands endemic plant, naturally-occurring populations of which are limited to San Miguel island due to the impacts of non-native mammals that were introduced in the 1800s. We are genotyping individuals both to understand the current genetic diversity on the landscape and to guide future seed collections and restoration efforts on San Miguel and Anacapa islands. Since 2015, we have worked in collaboration with partners on the conservation genomics and phylogenetics of the charismatic genus Dudleya (Crassulaceae), which has been heavily impacted in the wild due to plant poaching. Finally, we are building a DNA barcode library for San Nicolas Island that includes everything from lichens to vascular plants. We use this genetic information to examine the diet of rare species on the island, including the island foxes and snails.

The amazing lichens of California

Image of Flame dot lichenSome people say that lichens are fungi that have learned agriculture. That’s because a lichen is not just one organism—it is a little ecosystem consisting of one or more fungi that houses one or more photosynthetic partner. At least 1869 lichen species occur in California, but lichenologists are few and far between so there are undoubtedly more than 1869 species in the state. Because lichens are so understudied, we barely know which ones are endangered, or even worse, which ones have altogether disappeared. Only 13 lichens are officially listed as endangered in California, but several others should probably be included. The Garden lichenologist wants to learn EVERYTHING about California lichens, and she encourages their official listing as endangered when appropriate at the state, federal, and international levels.