Cheadle Center for Biodiversity and Ecological Restoration

Although California native bees are key pollinators for fruits and crops, they remain understudied compared to the Western honey bee. Examining morphological traits in native bees, such as pilosity, or hairiness, to understand taxonomic variation among species can inform and support conservation efforts. Three subspecies of long-horned bees, Melissodes tepidus timberlakei, M. tepidus yumensis, and M. tepidus tepida, occupy distinct regions across the western United States, but their morphological distinctions remain unclear. Pilosity, or hairiness, is a critical trait for thermoregulation, pollen collection, and species recognition, and may offer key insights into subspecies differentiation. I hypothesize that the three Melissodes tepidus subspecies differ significantly in pilosity coverage and lightness as adaptations to their unique ecological niches and climates. To test this hypothesis, I captured, stacked, and analyzed lateral images (both left and right sides) from five specimens per subspecies (totaling 30 images). Using a convolutional neural network explicitly trained for bee hair segmentation, I quantified hair coverage (percentage of hair pixels relative to body surface area) and lightness (numerical value of pixel lightness on a grayscale continuum). ANOVA analyses revealed no statistically significant differences among subspecies in either hair coverage (p = 0.129) or lightness (p = 0.207). Still, visual representations, such as boxplots and swarmplots, demonstrate M. tepidus yumensis to be hairier than M. tepidus tepida and M. tepidus timberlakei. This trend suggests that increasing the sample size may strengthen statistical significance and highlight pilosity differences. In the future, incorporating additional factors, such as sex differentiation, behavioral evidence, and genetic data, will enhance our understanding of subspecies divergence and inform more accurate conservation strategies.

Applying geometric morphometrics to assess morphological divergence in bees

Jorge De La Cruz, Charles N. Thrift, Madeleine M. Ostwald, Katja C. Seltmann 

University of California Santa Barbara

Bees have relatively conserved wing morphology, but the divergence between groups remains poorly understood and has not been thoroughly quantified. Wing venation characteristics are fundamental for defining and classifying insects, but traditional methods of morphological identification for structures with complex geometries are challenging and time-consuming. This poses a challenge to the ease and accessibility of biodiversity research and studies examining ecological morphotypes. In this study, we employed geometric morphometrics to assess divergence in wing vein morphology across bee taxa. Geometric morphometrics allows for detailed shape analysis of wing structure, which may provide insights into evolutionary relationships. By digitally landmarking nine homologous wing vein characters of a large sample of bees, we quantified and compared morphological variation across several recognized species, genera, and families to assess whether the resulting morphological clusters reflect evolutionary divergence. Previous exploratory analyses demonstrate the ability to differentiate species within a genus and even among populations, testifying to a high level of precision. The extent to which our groupings based on morphometric data align with established phylogeny and the effects of allometry are investigated. This study assesses the potential of geometric morphometrics to infer the phylogenetic placement of indeterminate bee species based solely on wing vein morphology and practical implications for an efficient species identification pathway.

This presentation was presented at the UCSB EEMB Undergraduate Research Symposium - 2025

Digital Extended Specimen Discussion Session presented at BioDigiCon. Biodiversity Digitization Conference (BioDigiCon) was held virtually on 27-29 September 2022 and hosted by iDigBio. https://www.idigbio.org/wiki/index.php/BioDigiCon_2022

Digital Extended Specimen Discussion Session organizers and presenters are Libby Ellwood, iDigBio; Katja Seltmann, Cheadle Center for Biodiversity and Ecological Restoration, UC Santa Barbara; Julie Allen, University of Nevada, Reno; Katie Pearson and Ed Gilbert, Symbiota Support Hub; Abby Benson, USGS

A video recording of the presentation is available in Supplementary Materials. https://escholarship.org/uc/item/0g99h7kf#supplemental

9 min Regular Session Talk for the Phycological Society of America (PSA) annual conference 2021

Observations of terrestrial species shifting their reproductive windows in response to climate change begs the question: Could this occur in aquatic environments too? Giant kelp, Macrocystis pyrifera, is the foundational species along much of California’s coastlines and islands, but in the aftermath of the 2015-16 El Nino on Catalina Island, it appeared to struggle to regain its dominance in the face of an invasive fucoid Sargassum horneri. As a part of a master’s studying the life history interactions between these two species, I performed monthly population and reproductive surveys, July 2018-August 2019, to address when each species was investing most in biomass, reproductive biomass, reproductive output and if there was a correlation between biomass and output in these species. The annual S. horneri dedicated much of its reproductive effort to a few short months in the spring (Feb.- April) and had a strong relationship between individual size and reproductive output. The perennial M. pyrifera peaked in reproductive output in late summer (July-August) and had a weak relationship between an individual’s size and reproduction. The observed timing was surprising as kelp is expected to peak in reproduction in the spring when upwelling is at its strongest. These observations on the kelp forests of Catalina could be an artifact of multiple stressful years of El Nino, heatwaves, and invasive species, but they also ask us to think about the assumptions we have about the classic timing & cycling of algal life histories.

The Eighth Annual Santa Barbara Botanic Garden Conservation Symposium for 2020 was themed “Children in Nature: Prescription for a Healthy Planet” and featured UCSB Environmental Studies professor Bridget Lewin, UCSB student Paulina Samosa, and Cheadle Center for Biodiversity and Ecological Restoration staff member Andy Lanes as panelists that present their experiences with environmental education and the Kids in Nature program along with a short video by Matt Fratus.

We introduce the Bee-Interaction-Database (BID), a project to create an open dataset about bee biotic interactions and other traits. Traits such as floral specialization, behavior, seasonality, parasites, nesting biology, body size and more may be included in the scientific literature, on natural history specimens, or observable in photographs (i.e., iNaturalist). Yet this information is often time-intensive to collect, hidden in the literature, and difficult to combine into one dataset because no uniform method for sharing traits and biotic information is used.

To date, we have extracted close to 3,000 unique bee observations from the scientific literature and integrated them into the Global Biotic Interactions (GloBI - https://www.globalbioticinteractions.org/), online infrastructure for sharing species interaction data. An early observation in our project is that trait data and interaction data are frequently part of the same recorded observation. In addition, authors frequently do not publish or include the raw data that goes into analyses, such as the study locality or specific interactions observed for the study. In conclusion, we hope to encourage new methods for publishing interaction and trait data that improves the reusability of research and provides authors a means of openly sharing trait data in the name of biodiversity research. https://github.com/Extended-Bee-Network/bee-interaction-database. This presentation was part of the 2020 Entomological Society of America meeting and was presented online.

California is a hotbed of floral and faunal species diversity. Santa Barbara County is a 4000 square mile area on the central California coast. It has four distinct ecoregions: Southern California Coast, Southern California Mountains and Valleys, Central California Coast, and Central Valley Coast which include chaparral and coastal sage scrub habitats. Santa Barbara County also includes four of the eight Channel Islands, which has a similar assemblage of habitats as the mainland, and a recent history of invasive ant eradication projects. In 2018, we began to compile an inventory of ant species that occur in the county, obtaining records from online digitized collections including AntWeb, GBIF, Symbiota Collections of Arthropods Network, Ecdysis, and iNaturalist. We included our own sampling from North Campus Open Space (NCOS), a recent coastal saltmarsh restoration site, and the Coal Oil Point Reserve (COPR), part of the UC Natural Reserve System. From this effort we found 66 species across 27 genera within Santa Barbara County including new records from our sampling sites. This checklist was built using Symbiota’s built-in check-list creation software. The coastal restoration sites proved to be less diverse and contain more invasive species than other areas within Santa Barbara County. In conclusion, the ongoing 2-year data collection from NCOS and COPR is a small part of a larger effort to expand the known ant species of Santa Barbara County. To provide a more comprehensive picture of the regional ant diversity, more targeted ant sampling in each ecoregion is needed.