skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Precision glycerine jelly swab for removing pollen from small and fragile insect specimens
1. Historical datasets can establish a critical baseline of plant–animal interactions for understanding contemporary interactions in the context of global change. Pollen is often incidentally preserved on animals in natural history collections. Techniques for removing pollen from insects have largely been developed for fresh insect specimens or historical specimens with large amounts of pollen on specialized structures. However, many key pollinating insects do not have these specialized structures and thus, there is a need for a method to extract pollen from these small and fragile insects. 2. Here, we propose a precision glycerine jelly swab tool to allow for the precise removal of pollen from old, small and fragile insect specimens. We use this tool to remove pollen from five families of insects collected in the late 1970s. Additionally, we compare our method with four previously published techniques for removing pollen from pinned contemporary specimens. 3. We show the functionality of the precision glycerine jelly swab for removing small quantities of pollen across insect families. We found that across the five methods, all removed pollen; yet, it was clear that some are better suited for fragile specimens. In particular, the traditional glycerine jelly swab and the precision glycerine jelly swabs both performed well for removing pollen from bee faces. The shaking wash resulted in specimen fracture and residue left behind, the ethanol rinses left setae matted, and the glycerol swabbing left residue on the specimen. Additionally, we present photographs documenting the effects of these methods on pinned honey bee specimens. 4. The precision glycerine jelly swab opens up opportunities to sample pollen from a variety of insects in natural history collections. These pollen samples can be incorporated into downstream analyses for pollen identification either via mi-croscopy or DNA sequencing, and the resulting plant–insect interaction data can establish historical baselines for contemporary comparison. Beyond our ap-plication of this method to pollen on insects, this precision glycerine jelly swab tool could be used to explore pollen placement specialization or to sample bryo-phyte, fungal and tree fern spores dispersing on animals.  more » « less
Award ID(s):
2011005
PAR ID:
10343710
Author(s) / Creator(s):
; ;
Editor(s):
Natalie Cooper
Date Published:
Journal Name:
Methods in Ecology and Evolution
ISSN:
2041-210X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Native bee species in the United States provide invaluable pollination services. Concerns about native bee declines are growing, and there are calls for a national monitoring program. Documenting species ranges at ecologically meaningful scales through coverage completeness analysis is a fundamental step to track bees from species to communities. It may take decades before all existing bee specimens are digitized, so projections are needed now to focus future research and management efforts. From 1.923 million records, we created range maps for nearly 88% (3158 species) of bee species in the contiguous United States, provided the first analysis of inventory completeness for digitized specimens of a major insect clade, and perhaps most important, estimated spatial completeness accounting for all known bee specimens in USA collections, including undigitized bee specimens. Completeness analyses were very low (3–37%) across four examined spatial resolutions when using the currently available bee specimen records. Adding a subset of observations from community science data sources did not significantly increase completeness, and adding a projected 4.7 million undigitized specimens increased completeness by only an additional 12–13%. Assessments of data, including projected specimen records, indicate persistent taxonomic and geographic deficiencies. In conjunction with expedited digitization, new inventories that integrate community science data with specimen‐based documentation will be required to close these gaps. A combined effort involving both strategic inventories and accelerated digitization campaigns is needed for a more complete understanding of USA bee distributions. 
    more » « less
  2. Research on plant-pollinator interactions requires a diversity of perspectives and approaches, and documenting changing pollinator-plant interactions due to declining insect diversity and climate change is especially challenging. Natural history collections are increasingly important for such research and can provide ecological information across broad spatial and temporal scales. Here, we describe novel approaches that integrate museum specimens from insect and plant collections with field observations to quantify pollen networks over large spatial and temporal gradients. We present methodological strategies for evaluating insect-pollen network parameters based on pollen collected from museum insect specimens. These methods provide insight into spatial and temporal variation in pollen-insect interactions and complement other approaches to studying pollination, such as pollinator observation networks and flower enclosure experiments. We present example data from butterfly pollen networks over the past century in the Great Basin Desert and Sierra Nevada Mountains, United States. Complementary to these approaches, we describe rapid pollen identification methods that can increase speed and accuracy of taxonomic determinations, using pollen grains collected from herbarium specimens. As an example, we describe a convolutional neural network (CNN) to automate identification of pollen. We extracted images of pollen grains from 21 common species from herbarium specimens at the University of Nevada Reno (RENO). The CNN model achieved exceptional accuracy of identification, with a correct classification rate of 98.8%. These and similar approaches can transform the way we estimate pollination network parameters and greatly change inferences from existing networks, which have exploded over the past few decades. These techniques also allow us to address critical ecological questions related to mutualistic networks, community ecology, and conservation biology. Museum collections remain a bountiful source of data for biodiversity science and understanding global change. 
    more » « less
  3. Butterflies and moths (Lepidoptera) comprise significant portions of the world’s natural history collections, but a standardized tissue preservation protocol for molecular research is largely lacking. Lepidoptera have traditionally been spread on mounting boards to display wing patterns and colors, which are often important for species identification. Many molecular phylogenetic studies have used legs from pinned specimens as the primary source for DNA in order to preserve a morphological voucher, but the amount of available tissue is often limited. Preserving an entire specimen in a cryogenic freezer is ideal for DNA preservation, but without an easily accessible voucher it can make specimen identification, verification, and morphological work difficult. Here we present a procedure that creates accessible and easily visualized “wing vouchers” of individual Lepidoptera specimens, and preserves the remainder of the insect in a cryogenic freezer for molecular research. Wings are preserved in protective holders so that both dorsal and ventral patterns and colors can be easily viewed without further damage. Our wing vouchering system has been implemented at the University of Maryland (AToL Lep Collection) and the University of Florida (Florida Museum of Natural History, McGuire Center of Lepidoptera and Biodiversity), which are among two of the largest Lepidoptera molecular collections in the world. 
    more » « less
  4. Abstract Compared to non‐urban environments, cities host ecological communities with altered taxonomic diversity and functional trait composition. However, we know little about how these urban changes take shape over time. Using historical bee (Apoidea: Anthophila) museum specimens supplemented with online repositories and researcher collections, we investigated whether bee species richness tracked urban and human population growth over the past 118 years. We also determined which species were no longer collected, whether those species shared certain traits, and if collector behavior changed over time. We focused on Wake County, North Carolina, United States where human population size has increased over 16 times over the last century along with the urban area within its largest city, Raleigh, which has increased over four times. We estimated bee species richness with occupancy models, and rarefaction and extrapolation curves to account for imperfect detection and sample coverage. To determine if bee traits correlated with when species were collected, we compiled information on native status, nesting habits, diet breadth, and sociality. We used non‐metric multidimensional scaling to determine if individual collectors contributed different bee assemblages over time. In total, there were 328 species collected in Wake County. We found that although bee species richness varied, there was no clear trend in bee species richness over time. However, recent collections (since 2003) were missing 195 species, and there was a shift in trait composition, particularly lost species were below‐ground nesters. The top collectors in the dataset differed in how often they collected bee species, but this was not consistent between historic and contemporary time periods; some contemporary collectors grouped closer together than others, potentially due to focusing on urban habitats. Use of historical collections and complimentary analyses can fill knowledge gaps to help understand temporal patterns of species richness in taxonomic groups that may not have planned long‐term data. 
    more » « less
  5. Scientific collections hold value in a wide range of fields, from conservation to species-restoration. However, many are unaware of collections’ direct contributions to scientific discovery. Collections are a key source of data, but may not be emphasized to emerging scientists as such. While institutions make collections more accessible, preserved specimens may be misunderstood as nothing more than static, dead creatures in cabinets. To combat this, I created a StoryMap on the history of specimen collections and how they have changed, with case-studies and interviews from the California Academy of Sciences that illuminate collections’ roles in modern conservation. StoryMaps are interactive multimedia pieces that present information in novel, highly engaging ways. This more-accessible medium allows for an easily digestible story encompassing 100 years of specimen-collection. Participants between the ages of 18-25 will answer questions before and after reading the StoryMap to gauge how perceptions of the value of scientific collections have changed. Ultimately, this project endeavors to leave young adults with a deeper appreciation for specimen collections and thus contribute to them centering specimens in future decision-making. Young adults are a key generation that is shaping the future of science. Thus, comprehending the value of specimen collections is paramount to ensuring collections are adequately supported in the future, and that research in species conservation continues. As technology rapidly advances, the value of specimen collections grows, and supporting their stewardship ensures access to historical data as new research questions emerge. 
    more » « less