My research interests are at the intersection of ecology and systematics. As an ecologist, I strive to understand the relationships between organisms and the environment in relation to altered habitats. As a systematist, I focus on species delimitation to estimate both functional niche groups and species distributions. I consistently turn to behavioral data, phylogenomics, and natural history collections to address questions pertaining to biogeography, evolution, and environmental sustainability. Aside from this research, mentoring the next generation of independent critical-thinkers about the vast worlds of both ecology and systematics is an additional interest and a core personal value. My research is thus driven by three fundamental statements:

• Tracking shifts in hosts and ranges in response to environmental changes require baseline distribution data supported by taxonomic revisions.

• Specimens within natural history collections provide a broad range of information; studying these collections will aid in understanding biogeography and evolution without the explicit need to conduct more sampling, thus saving time, energy, finances, and most importantly environmental integrity.

• Inviting and including a diverse cohort of mentees to support further work in areas of conservation and sustainability, as well as providing professional development opportunities, is a core component in any mentor-mentee or research program.

The uniqueness and vast amounts of data housed at natural history collections provides countless avenues to address biodiversity, habitat, and climate change. I, as a trained entomologist, am interested in continuing to use insect abundances, habitat, hosts, and behaviors to address my research questions and to help others achieve their research goals.

Past Entomological Research

Bee Diversity Responses to Landscape Management

Bee diversity, and not just honeybee abundances, is an important ecological indicator of a healthy, resilient environment. During my Masters of Science degree in entomology at the University of Illinois at Urbana-Champaign, I collaborated with the Illinois Department of Natural Resources to examine the effects of their prescribed burn practices on bees in the tallgrass prairies of central Illinois. The management implications of this study were in desperate need, as no information on bee responses to dormant-season versus growing-season prescribed fires had been recorded for this area with a history of naturally-occurring fires1. The IDNR at the time was beginning to incorporate growing season burns, as had been done in southeastern forests2, into their fire regime with no data on invertebrate impacts. My study showed there were no differences between bee abundances or nesting guilds (above vs below ground) and time of prescribed fires (dormant, winter burns versus early or late summer growing season burns). This provided the IDNR evidence that prescribed fires could be conducted during a longer period of the year and also showed evidence that these burns bolstered bee diversity compared to unmanage areas3. 

This study also initiated a collaboration on creating an Illinois bee species checklist, the first of its kind for the state4. By using museum records and new studies conducting research in under-sampled areas in southern Illinois, we were able to provide a preliminary checklist and county records. This list has already served as a reference for further analysis on range shifts and new state and county records5.

New Species and Insights into Behavioral Evolution

Describing new species has historically focused on color differences. This is especially the case with wasps in the family Pompilidae. Since most work was conducted in the 1950s, newly collected material and the implementation of genomic data have allowed me to address discrepancies in species level taxonomy. Specifically with a genus that uses temporary paralysis to subdue spider hosts, Minagenia Banks, 1934, there have been no recent revisions even though there are many undescribed species. Working with international collaborators, I described a new species from Australia and am currently describing species from Africa and the Nearctic6. Entomology collections have greatly added to the ease of descriptions, without the need to extensively collect new specimens in hazardous (physically or permit and regulatory restricted) global areas.

This wonderful world of wasps extended further into pompilid behavioral evolution. While female spider wasps all hunt for and lay a single egg on the abdomen of a spider, their behavioral patterns are diverse. For 70 years, a single linear hypothesis for pompilid behavioral evolution has held the long-debunked simple-to-complex evolutionary progression7. And while some transitions are still seen after extensive ultraconserved element (UCE) analyses, pompilid behaviors are highly plastic evolutionarily, like many other recent studies including courtship complexity displays in birds-of-paradise8 and courtship patterns of the parasitoid wasp Mellitobia9. The manuscript is currently in preparation, but the initial findings were presented in the 2023 Virtual Evolution Conference on June 1, 2023. This is an ongoing study, with additional international collaborators recently joining the project.

Plans for Continuing and Future Research

There is still so much to learn from museums and natural history collection specimens. The planet is changing at a faster rate than in previous millenia10, with an increase in more severe natural disaster occurrences compared to the early 1990s11. Even at the microclimate level, within forests or desert environments, slight shifts may cause acute changes of flora and fauna12. Every living creature must respond in some way to these environmental shifts. In many cases, however, it is difficult to characterize such shifts because there is a lack of baseline data, a measurement by which to compare current distributions and predict future range shifts. A natural history collection, even with their inherent data biases, can be the best starting point for determining current and historical ranges, species diversity, and microbial (including viral) strains within a given region.

My research questions have remained tied to habitat change and ecological responses to environmental conditions: 

• What are historical and current distributions of taxa by ecological guild?

• How may non-lethal sampling aid in tracking habitat shifts of small and cryptic species? 

• Can we generalize responses to environmental changes from known ecology or ecology hypothesized by morphometrics? 

The output of these research questions includes several sets of data: creating or compiling species lists by state and habitat type to provide baseline distribution data, along with known ecological behaviors or habitat requirements, and providing reference lists; sequencing specific genes or conducting other targeted enrichment methods (such as UCEs and eDNA) to track and confirm species; and creating morphology matrices to track variation as a measure of response to potentially shifting environments.

Because research is not done in isolation, it is important to also include the mentoring of future researchers and the teaching of this material. Attending, presenting, and networking at conferences is a general way to communicate information and job opportunities with those who are also in attendance and may share research interests, but it is not the only avenue that should be taken. Special topics and elective course offerings at universities can allow for broader exposure to real-world applications of curriculum content. I designed and taught a course on collection material handling, introducing students from medical to technical writing departments to museum object care and grant writing13. This not only got these students from varied departments participating in activities like art acquisition and ichthyology collection assessment, but brought many perspectives on addressing biased survey methods and implementation of education theories. Though a greater proportion of academic positions may be research and instructing general coursework, having the opportunity to design and instruct other courses only broadens a student's academic experience.

References:

1. Higgins, K.F. (1984). Lightning fires in North Dakota grasslands and in pine-savanna lands of South Dakota and Montana. Journal of Range Manage. 37:100–103.

2. Campbell, J.W., P.A. Vigueira, C.C. Viguiera, and C.H. Greenberg. (2018). The effects of repeated prescribed fire and thinning on bees, wasps, and other flower visitors in the understory and midstory of a temperate forest in North Carolina. Forest Science. 64(3):299–306.

3. Decker, B.L., and A.N. Harmon-Threatt. (2019). Growing or dormant season burns: the effects of burn season on bee and plant communities. Biodiversity and Conservation. 28: 3621-3631.

4. Decker, B.L., C. Bryan, L. Kassim, N. Soley, S.D. Sipes, M. Arduser, and A.N. Harmon-Threatt. (2020a). Preliminary Illinois bee species checklist (Hymenoptera: Apoidea) and use of museum collections. Journal of the Kansas Entomological Society. 93(1): 34-74.

5. Veit, M.F., J.S. Ascher, J. Milam, F.R. Morrison, and P.Z. Goldstein. (2022). A Checklist of the Bees of Massachusetts (Hymenoptera: Apoidea: Anthophila). Journal of the Kansas Entomological Society. 94(2):81–157. https://doi.org/10.2317/0022-8567-94.2.81.

6. Decker, B.L., J.P. Pitts, D. Yuan, and J. Rodriguez. (2020b). Re-examination of Australian and Oriental species of Minagenia Banks, 1934 (Hymenoptera: Pompilidae), with a new record for the genus in Australia and a new species description. Zootaxa. 4768(3):10.11646/zootaxa.4768.3.5.

7. Evans, H.E. (1953). Comparative ethology and the systematics of spider wasps. Systematic Zoology. 2(4):155-172.

8. Logon, R.A., Diaz, C.D., Morano, J.L., Troscianko, J., Stevens, M. Moskeland, A., Laman, T.G., & Scholes, E. (2018). Evolution of correlated complexity in the radically different

9. courtship signals of birds-of-paradise. PLOS Biology.

10. Tanner, D.A., J.M. González, R.W. Matthews, S.B.Vinson, and J.P. Pitts. (2011). Evolution of the courtship display of Melittobia (Hymenoptera: Eulophidae). Molecular Phylogenetics and Evolution. 60(2): 219-227.

11. IPCC. (2001). “Climate Change 2001: The Scientific Basis. Contribution of Working Group I to the Third Assessment Report of the Intergovernmental Panel on Climate Change”. Cambridge: Cambridge University Press.

12. Our World in Data. (2023). “Number of recorded natural disaster events, 1900 to 2023”. Accessed 3 Oct. 2023 from https://ourworldindata.org/grapher/number-of-natural-disaster-events

13. Lembrechts, J.J., and I. Nijs. (2020). Microclimate shifts in a dynamic world. Science 368:711–712. DOI:10.1126/science.abc1245.

14. Decker, B.L., and M. Cannon. (in prep). Providing hands-on museum experiences using campus museum resources. ETE Journal.