Evolutionary Microbiology

Kathryn Herr, Ph.D.

Researcher in insect–microbe symbiosis

  • NIH IRACDA FIRST Postdoctoral Teaching Fellow, Emory University (2024–25)
  • Ph.D. Microbiology, Cornell University
  • Based in Bath, UK · right to work in the UK (High Potential Individual visa)

I study how microbes and the plants and animals that host them shape one another, from fluorescent bacteria that influence aphid behaviour to the yeasts that travel with a burying beetle. I combine fieldwork, microbiology, and bioinformatics to ask evolutionary questions about everyday symbioses. Alongside that research I teach undergraduate biology and microbiology, and supervise students through research projects of their own.

Academic path

  1. Emory University crest
    2024 – 2025

    Emory University

    IRACDA FIRST Postdoctoral Teaching Fellow, Dept. of Biology

    NIH Institutional Research and Academic Career Development Award (IRACDA), Fellowships in Research and Science Teaching. Independent research paired with mentored teaching at a partner institution, Morehouse College.

  2. Cornell University crest
    2018 – 2024

    Cornell University

    Ph.D., Microbiology

    Dissertation: The symphony of symbiosis: ecological and evolutionary impacts of microbial interactions with insects.

  3. Willamette University crest
    2012 – 2016

    Willamette University

    B.A., Biology (minors in Chemistry & Chinese)

    Thesis: Secreted extracellular polysaccharide layer prevents phage binding on Caulobacter crescentus.

Research

How do microbes and their animal or plant hosts shape one another over evolutionary time?

Phyllosphere Pseudomonas and aphid behaviour

Pseudomonas spp. · pea aphids

Leaf surfaces carry dense and variable bacterial communities, and the insects feeding there meet those microbes first. For my dissertation I tested how common fluorescent Pseudomonas from the phyllosphere affect aphid behaviour. Different bacterial strains changed that behaviour in substantially different ways, which matters for how these everyday, non-obligate symbioses evolve.

Burying beetles and their Yarrowia symbionts

Nicrophorus spp. · Yarrowia-like yeasts

Burying beetles (Nicrophorus spp.) locate, bury and preserve small vertebrate carcasses, and carry yeast symbionts with them while they do it. Sampling wild populations in the Adirondack Mountains, I examined how diverse these Yarrowia-like yeasts are across beetle species and what their evolutionary history says about how the association is maintained.

Caulobacter exopolysaccharide and phage defence

Caulobacter crescentus · bacteriophage

Caulobacter crescentus secretes an extracellular polysaccharide layer that prevents bacteriophage from binding to the cell. Using confocal microscopy, fluorescent proteins and plaque assays, I measured that layer across diverse strains and how well each resisted infection. Strains investing more in exopolysaccharide grew more slowly, a trade-off between protection and proliferation.

Insecta Eukaryota Bacteria
  • Nicrophorus spp. Coleoptera · burying beetles and their yeast symbionts
  • Pea aphids Hemiptera · insect host responding to leaf-surface microbes
  • Yarrowia-like yeasts Ascomycota · symbionts carried by burying beetles
  • Pseudomonas spp. Gammaproteobacteria · fluorescent phyllosphere bacteria
  • Caulobacter crescentus Alphaproteobacteria · exopolysaccharide trade-offs and phage defence
The organisms I work with, and how they are actually related. Topology only: branch lengths carry no information, and only taxa from my own research are sampled.

Teaching

  • BIO306: Principles of Microbiology

    Instructor · Morehouse College

    Co-taught this established upper-level course and redesigned parts of it to bring in more active learning and student-centred work, including spreading assessment across more and smaller assignments to make the course more accessible. Wrote, marked and built rubrics for seven assignments, a group project and four unit exams. Taught the unit on microbial interactions and applied microbiology on my own, co-taught the unit on microbial history and cell structure, and held weekly in-person and online office hours.

  • BIOMI 6300: Computational Approaches for Microbial Systems

    Guest Instructor · Cornell University

    Designed learning outcomes and built a case study from my own research to teach upper-level bioinformatic analysis of next-generation sequencing data, using active learning (think-pair-share, live polling) to explore trade-offs between genomic and metagenomic, shallow and deep sequencing.

  • Software Carpentry Workshop

    Workshop Helper · Cornell University

    Gave one-on-one support across a three-day workshop, helping attendees install and use R, RStudio, and GitHub, and troubleshooting issues across Mac, Windows, and Linux.

  • BioG 1500: Investigative Biology

    Guest Lecturer & Graduate Teaching Assistant · Cornell University

    Lectured the full 300-student course on the scientific method and hypothesis building, and taught two 3-hour, 18-student lab sections a week. Guided small groups from writing a research proposal on green algae and nutrient limitation through to experimental design, data analysis in R and Excel, figures, and a written scientific article, and supervised the undergraduate teaching assistants supporting the sections.

  • BIOMI 2600: Microbiology of Human Contagious Diseases

    Graduate Teaching Assistant · Cornell University

    Facilitated remote discussions on infectious disease and microbiology, held office hours and small-group review sessions, wrote exam questions, and moved lecture and assessment materials onto Canvas, using its analytics to find where students were struggling.

  • BIOMI 1100: College Dorm Microbiology

    Graduate Teaching Assistant · Cornell University

    Led three weekly 2-hour discussion sections connecting microbiology to everyday life, and guided students through independent projects: writing a proposal, sampling and culturing a microbial community of their own choosing, then analysing the resulting 16S data and writing it up as a scientific article.

  • Microbial Friends and Foes Summer REU

    Guest Lecturer & Graduate Teaching Assistant · Cornell University

    Designed and taught a recurring workshop on how to read scientific articles for undergraduates from underrepresented backgrounds, and served as a teaching assistant and student liaison for the broader summer research program.

  • BIOMI 2500: Public Health Microbiology

    Graduate Teaching Assistant · Cornell University

    Taught in a flipped classroom where students met concepts through coursework and worked problems in class, guiding small groups through public health case studies and encouraging them to reason through unfamiliar material independently.

  • BIO250: Microbiology (Lab)

    Teaching Assistant · Willamette University

    Supported students in designing and running independent microbiology experiments, set up the laboratory space each week, and prepared all media and reagents.

  • BIO130: Cell Biology & Genetics

    Teaching Assistant · Willamette University

    Held office hours and exam review sessions, and graded coursework throughout the term.

Teaching training

  • Project Management for Postdoctoral Researchers

    Emory University · Project management · mentoring
  • FIRST “How To Teach”

    Emory University · Teaching · pedagogy
  • BIOG 6500: Biology Instructor Training

    Cornell University · Teaching · pedagogy
  • Teaching & Learning in the Diverse Classroom

    Cornell University · Teaching · inclusive practice
  • ENTOM 4040: Diversity, Equity & Inclusion

    Cornell University · Teaching · inclusive practice

Mentoring

I have advised and supported seven undergraduate researchers through independent projects: three over six years in the Hendry Lab at Cornell, three summer researchers on the Microbial Friends and Foes REU, and an honours research student during my postdoc at Emory. Mentoring is one of the most rewarding parts of the job, and it shapes how I teach.

Skills & Tools

Teaching & Curriculum

Course design & redesign Lecturing (300+ students) Laboratory teaching Learning outcomes Assessment & rubric design Marking & feedback Active learning Flipped classroom Inclusive teaching practice Project supervision Moodle-like systems Online teaching & delivery Workshop delivery

Bioinformatics & Computation

Bash Python R / R Markdown Git / GitHub Docker / Singularity Jupyter / Binder SPAdes / Discovar BWA / Bowtie2 / SAMtools FastQC / CheckM / BUSCO BLAST / RAST / Braker2 MEGA / MetaPhlAn / PhyloPhlAn

Laboratory & Field

Sterile technique & culturing Confocal microscopy Fluorescent proteins Plaque & phage assays Plate reader assays ImageJ DNA synthesis & Sanger sequencing Insect behavioural assays Field sampling & transects Media & reagent preparation

Publications

View on ORCID
  1. Common fluorescent Pseudomonas in the phyllosphere can influence aphid behavior in diverse ways
    Herr, K., Schieber, J., & Hendry, T. A. (2024)
    bioRxiv
  2. Draft genome sequences of eight bacterial isolates from Pisum sativum leaf surfaces
    Smee, M. R., Herr, K. L., Abdul-Khaliq, S., Cadet, C. E. A., & Hendry, T. A. (2024)
    Microbiology Resource Announcements, 13(1), e00813-23
  3. The Lizard Gut Microbiome Changes with Temperature and Is Associated with Heat Tolerance
    Moeller, A. H., Ivey, K., Cornwall, M. B., Herr, K., Rede, J., Taylor, E. N., & Gunderson, A. R. (2020)
    Applied and Environmental Microbiology, 86(17), e01181-20
  4. Exopolysaccharide production in Caulobacter crescentus: A resource allocation trade-off between protection and proliferation
    Herr, K. L., Carey, A. M., Heckman, T. I., Chávez, J. L., Johnson, C. N., Harvey, E., Gamroth, W. A., Wulfing, B. S., Van Kessel, R. A., & Marks, M. E. (2018)
    PLOS ONE, 13(1), e0190371

Funding & Awards

  • NIH IRACDA FIRST Postdoctoral Fellowship

    Emory University

    NIH Institutional Research and Academic Career Development Award (IRACDA), Fellowships in Research and Science Teaching.

  • Provost Diversity Fellowship for Advanced Doctoral Students

    Cornell University · $16,247

    A competitive one-term fellowship, covering stipend and tuition, for advanced Ph.D. students who have contributed to Cornell's work on inclusion and belonging.

  • Graduate Student Research Enhancement Award

    The Coleopterists Society · $1,991

    Examining the diversity of burying beetles (Nicrophorus spp.) and their associated Yarrowia symbionts in the Adirondack Mountains.

  • Kieckhefer Adirondack Fellowship

    Cornell University · $979

    Fieldwork on burying beetles (Nicrophorus spp.) and their associated Yarrowia symbionts in the Adirondack Mountains.

  • CALS Outstanding Teaching Assistant Award

    Cornell University

    Awarded for teaching BIOMI 1100: College Dorm Microbiology and BIOMI 2500: Public Health Microbiology.

  • Microbiome Hackathon: Best Presentation

    Cornell University

Talks & Posters

  • The Symphony of Symbiosis: Ecological and Evolutionary Impacts of Microbial Interactions with Insects

    Conference Talk

    CIHMID Summer Symposium, Cornell University

  • The Symphony of Symbiosis: Ecological and Evolutionary Impacts of Microbial Interactions with Insects

    Invited Talk

    Dissertation Seminar, Cornell University

  • An Investigation into Yarrowia-like Yeast Symbionts of Burying Beetles (Nicrophorus spp.)

    Invited Talk

    Microbiology Department Seminar, Cornell University

  • Investigating the Relationship Between Burying Beetles (Nicrophorus spp.) and Associated Microbial Symbionts

    Poster

    Animal-Microbe Symbioses, Gordon Research Conference, Lucca, Italy

  • Evolution of Yeast Symbionts from Burying Beetles (Nicrophorus spp.)

    Poster

    Animal-Microbe Symbioses, Gordon Research Seminar, Lucca, Italy

  • An Investigation into Burying Beetle (Nicrophorus spp.) Symbionts

    Conference Talk

    Evolution Meeting, Cleveland, OH

Outreach

  • Write a Researcher (WAR)

    Vice President

    A pen-pal program connecting high school students across the country with research mentors at Cornell University. I helped build and run the program from its first year, when it reached 200 high-school participants nationwide, and worked with Cornell to waive the graduate-school application fee for our participants.

  • GRASSHOPR

    Teaching Fellow

    The Graduate Student School Outreach Program connects STEM researchers with K-12 students in underrepresented districts of Tompkins County, NY. I co-developed and taught multi-day lesson plans for elementary classrooms on decomposition, immunity, and the history of microbiology, spotlighting diverse and underrepresented microbiologists.

  • Expanding Your Horizons (EYH)

    Buddy

    A yearly conference for hundreds of 7th–9th grade students from backgrounds underrepresented in STEM. I escorted student groups through a day of hands-on scientific learning.

Other Notable Research & Lab Experience

  • Production Associate I

    Blue Heron Biotech, LLC · Bothell, WA

    Performed DNA synthesis and sequence analysis within a multi-disciplinary team, meeting accuracy and throughput goals on the company's proprietary gene-synthesis platform. Ran Sanger sequencing and helped maintain the lab's pipetting robots.

  • Field Technician

    Willamette University, Dept. of Biology · Delamar Valley, NV

    Studied the coevolution of Joshua trees (Yucca brevifolia) and yucca moths (genus Tegeticula) as part of a five-person field team under demanding desert conditions: surveying insect populations, running transects of Joshua tree seedlings, and collecting samples for lab analysis.

  • Laboratory Technician

    Willamette University, Dept. of Biology · Salem, OR

    Researched evolutionary competition in Caulobacter crescentus using confocal microscopy, fluorescent proteins, and plaque assays to characterize extracellular polysaccharide layers across diverse strains. Supervised three junior research students and wrote up the work as a first-author publication.