I wish to respectfully acknowledge first the Tohono O’Odham, Akimel O’Odham, and Yaqui Nations, on whose occupied land I conducted fieldwork for my thesis. I also wish to acknowledge the Lenni-Lenape people, on whose land Drexel University stands, and the Nations of the Haudenosaunee Confederacy, on whose occupied land I was raised and learned to love the earth. Indigenous people, still struggling for equality on lands that were taken from them, have studied, managed, and cared for these lands and organisms for thousands of years to the present day.

How do behavior, morphology, and development shape brain resource allocation patterns?

In the lab of Sean O’Donnell at Drexel University I’ve become fascinated by the factors that shape the insect brain. Particularly interesting is the effect of variation in behavior, as the result of caste differentiation (in paper wasps and army ants), task allocation (in stingless bees, in collaboration with Kaitlin Baudier), or alternative reproductive tactics (a piece of my thesis work in Centris pallida and Amegilla dawsoni bees, in collaboration with Stephen Buchmann). Finally, I am excited for a newly funded collaboration with Katherine Fiocca studying the impact of nutrition on brain resource allocation and dominance behaviors in a primitively social paper wasp.

  • O’Donnell S, Bulova S, DeLeon S, Barrett M, Fiocca K (2017). Caste differences in the mushroom bodies of swarm-founding paper wasps: implications for brain plasticity and brain evolution (Vespidae, Epiponini). Behavioral Ecology and Sociobiology, 71:116.
  • O’Donnell S, Bulova S, Barrett M, von Beeren C (2018). Worker-caste differences in brain investment reflect soldier behavioral specialization (Eciton army ants, Formicidae: Dorylinae). BMC Zoology, 3:3.
  • In Prep (BMC Zoology) Baudier K, Bennett M, Barrett M, Cossio F, O’Donnell S, Fewell J, Harrison J, Pavlic T. Modality-specific neural investment in age-based defensive task transition of stingless bee soldiers (Tetragonisca angustula).

The lab is also fascinated by how body size, morphology, and development shape the insect brain, using wasps, bees, roaches, and termites. In collaboration with Stefan Bonestroo and Susan Bulova, the lab has been working to understand shifts in brain resource allocation across development and between sexes in Cryptocercus wood roaches and Zootermopsis termites.

  • O’Donnell S, Bulova S, DeLeon S, Barrett M, Fiocca K (2019). Brain structure differences between solitary and social wasp species are independent of body size allometry. Journal of Comparative Physiology A, DOI 10.1007/s00359-019-01374-w.
  • O’Donnell S, Bulova S, Barrett M, Fiocca K (2018). Size constraints and sensory adaptation in   brain architecture (paper wasps – Vespidae: Epiponini). Biological Journal of the Linnean Society, blx150.

Photo credit to Bruce Taubert

How does morphology and microclimate use affect the mating behaviors of Centris pallida male bees?

The main focus of my thesis is to understand how the different male C. pallida morphs might respond to increasing environmental temperatures, given the different behaviors and morphologies they utilize to access mates. Through a combination of thermal maxima assays, environmental modeling, UV-VIS-NIR reflectance study, and morphological descriptions, I aim to determine differences in the thermal environments in which these males behave and how these differences might impact their mating behaviors.

What is the impact of the polyols erythritol and mannitol on insect survival and development? 

Studying the impact of polyols on insect development and survival is a long-standing collaboration between the O’Donnell and Marenda labs after a 2014 breakthrough by Dr. Marenda’s son for his school science project on the use of Truvia as an insecticide (thanks to the compound erythritol).

  • Caponera V, Barrett M, O’Donnell S, Marenda D (2020). Erythritol causes concentration-dependent mortality in the Eastern subterranean termite (Blattodea: Rhinotermitidae). Journal of Economic Entomology, toz260.
  • Barrett M, McNair C, Caponera V, O’Donnell S, Marenda D (2020). Potential for use of erythritol as a socially-transferrable ingested insecticide for ants (Hymenoptera: Formicidae). Journal of Economic Entomology, toaa019.
  • Barrett M1, Fiocca K1, Waddell E, McNair C, O’Donnell S, Marenda D (2019). Larval mannitol diets increase mortality, prolong development, and decrease adult body sizes in fruit flies (Drosophila melanogaster). Biology Open, 8: bio047084. (1 = Co-first author)
  • Fiocca K1, Barrett M1, Waddell E, Vivieros J, McNair C, O’Donnell S, Marenda D (2019). Mannitol ingestion causes concentration-dependent, sex-biased mortality in Drosophila melanogaster. PLoS One, 14: e0213760.

Natural history: Where it all begins

Observing, puzzling over, and listening to the world around me is one of the things about my studies that brings me the most joy. I am working with Dan Papaj and Stephen Buchmann to study the progression of ovary development in solitary Centris cockerelli, Centris caesalpiniae, and Centris pallida females from emergence through mating, foraging, and nesting.

Meredith Johnson, John Alcock, Buchmann and myself are all working together to study the mating and nesting behaviors of the poorly studied C. caesalpiniae after coming across a massive aggregation in spring of 2020. Buchmann and myself have also been studying C. cockerelli mating behaviors since spring of 2018 and are planning to report on new information related to the C. pallida ART system that we have studied since 2018. I was also lucky to discover the first C. pallida gynandromorph this year at my field site in Tucson.

  • In Review (Journal of MelittologyBarrett M. The first case of gynandromorphy in Centris pallida (Fox). 

A happy accident occurred in 2018 when solitary Isodontia wasps moved into my bee houses in NY; studying the adult morphology, communal brood chambers, sex allocation ratios and prey associations of Isodontia auripes has been a true joy, as they reoccurred in my nests last summer.

Sam Droege and collaborators with the USGS bee lab put together a lovely project on mandible overlap patterns in bees that I was lucky to contribute to, manuscript forthcoming.

Inclusive, evidence-based scholarship of teaching and learning

There is nothing more exciting than a community of scholars committed to using the most successful and inclusive methods possible for teaching students science! Working with colleagues in the Drexel School of Education and the Department of Biology, I am grateful to have the opportunity to participate in developing, implementing, and sharing techniques, tools, and strategies that will help K12 and college level educators engage and teach their classes. Below are publications related to scholarship of teaching and learning, but you can read more about all my teaching, mentorship, and outreach efforts.

  • In Review (Afterschool Matters) Ibarrola Recalde GD1, Barrett M1, Black W, Songer NB. Extending Philly Scientists: How to use hands-on summer learning for biodiversity lessons and career awareness.
  • In Prep (Course Source) Barrett M, Mitchell M, Gurney S. Guided worksheet to develop process skills using real data in a university Biology classroom.