About

Jeremy Draghi is an Associate Professor of Biological Sciences at Virginia Tech, located in Derring Hall on the Blacksburg campus. His educational background includes a Ph.D. in Ecology and Evolutionary Biology from Yale University, obtained in December 2008, and a B.S. in Biology and a B.A. in Physics from the University of Connecticut in 2002. He has held positions as an Assistant Professor at Brooklyn College CUNY and The Graduate Center CUNY, where he worked from 2015 to 2019, focusing on Ecology, Evolutionary Biology, and Behavior, as well as Molecular, Cellular, and Developmental Biology. His postdoctoral research includes positions at the University of British Columbia in the Department of Zoology under advisor Michael Whitlock, and at the University of Pennsylvania in the Department of Biology under advisor Joshua Plotkin. Dr. Draghi's research focuses on evolutionary biology, with a particular emphasis on ecology and evolution, as evidenced by his academic appointments and research activities. His contributions to the field have been recognized through awards such as the Nicholas Prize Thesis Award in 2009 and a NASA Graduate Student Research Program Fellowship from 2005 to 2008.

Research topics

• Computer Science
• Evolutionary biology
• Genetics
• Artificial Intelligence
• Biology
• Computational biology
• Ecology
• Neuroscience
• Physics

Selected publications

• Epigenetic variation can promote adaptation by smoothing rugged fitness landscapes

  Proceedings of the Royal Society B Biological Sciences · 2026-02-11

  articleOpen accessSenior author

  Heritable non-genetic phenotypic variation-broadly, epigenetics-can potentially influence evolutionary outcomes as direct targets of selection or through interactions with genetic variation. While their evolutionary benefits in generating phenotypic diversity in changing environments are well-characterized, there has been relatively little consideration of how the joint influence of epigenetic changes and mutations would affect traversal of multi-peak adaptive landscapes. Here, we discover general principles for how epigenetics, by generating an epigenetic quasispecies (clusters of semi-stable phenotypes mapped to a single genotype), tends to improve adaptive outcomes of an asexual population on rugged fitness landscapes even in a constant environment. In particular, rapid epigenetic changes tend to smooth out suboptimal fitness peaks through incorporating fitness contributions of epimutations, allowing access to better adaptive outcomes. Remarkably, the average impact of epigenetics is more strongly influenced by an approximate balance between switching rates rather than the absolute rate at which switching occurs. These findings demonstrate that epigenetic changes can be influential even without having strong heritability and have a striking, yet generally invisible, beneficial role in shaping a population's adaptive trajectory.

  PublisherOA PDFDOI

• Evolutionary rescue of niche constructors from habitat exploitation: Fecundity costs can promote rescue

  Evolution · 2025-04-25 · 1 citations

  articleOpen accessSenior author

  Organisms can improve their fitness by modifying their environments-a process known as (positive) niche construction. Since niche construction is inherently costly, requiring time and energy to perform, niche constructors are vulnerable to displacement by non-niche-constructing invaders that exploit the constructed habitats. One way constructors could avoid such displacement is by adapting to withstand the invaders and thus undergoing evolutionary rescue. Here, we first analytically approximate the probability that a niche-constructing population-one building reproductive habitats-undergoes evolutionary rescue from habitat exploitation by an invading species. Then, we evaluate the approximation under two different fitness costs of construction: a fecundity cost and a mortality cost. We find that fecundity costs are not only less harmful than mortality costs but can even promote rescue compared with no costs by reducing the rate at which constructors attempt reproduction and thus construction. The resulting lower habitat density slows invasion, which then buys constructors more time to mutate. This invasion-slowing benefit can be stronger if the fecundity cost, instead of deriving from construction, stems from niche destruction, where organisms destroy their own habitats. Our results suggest that the same fitness costs rendering constructors vulnerable to habitat exploitation can help rescue constructors from such exploitation.

  PublisherDOI

• Epigenetic variation can promote adaptation by smoothing rugged fitness landscapes

  bioRxiv (Cold Spring Harbor Laboratory) · 2025-06-09 · 1 citations

  preprintOpen accessSenior author

  Abstract Heritable non-genetic phenotypic variation—broadly, epigenetics—can potentially influence evolutionary outcomes as direct targets of selection or through interactions with genetic variation. While their evolutionary benefits in generating phenotypic diversity in changing environments is well-characterized, there has been relatively little consideration of how the joint influence of epigenetic changes and mutations would affect traversal of multi-peak adaptive landscapes. Here, we discover general principles for how epigenetics, by generating an epigenetic quasispecies (clusters of semi-stable phenotypes mapped to a single genotype), tends to improve adaptive outcomes of an asexual population on rugged fitness landscapes even without environmental change. In particular, rapid epigenetic changes can sometimes smooth out suboptimal fitness peaks through incorporating fitness contributions of epimutations, allowing access to better adaptive outcomes. Remarkably, the average impact of epigenetics is more strongly influenced by an approximate balance between switching rates rather than the absolute rate at which those switches occur. These findings demonstrate that epigenetic changes can be influential even without having strong heritability and have a striking, yet generally invisible, beneficial role in shaping a population’s adaptive trajectory. Significance Statement Selection can act upon individuals with epigenetic differences, but it is unclear how much long-term effect this can have on evolutionary trajectories if the epigenetic changes only last a limited number of generations. When the environment changes or more than one functionality is needed simultaneously, it is apparent how bet hedging or division of labour can be advantageous, but what about in a single, constant environment? Here, we find that epigenetics, by allowing individuals rapid yet heritable access to multiple alternate phenotypes, can change the outcome of genetic evolution and has the tendency to remove local fitness peaks and allow adaptation to find higher optima. As such, epigenetics, despite being transient, can profoundly affect adaptive trajectories.

  PublisherOA PDFDOI

• Spatial clustering of hosts can favor specialist parasites

  Ecology and Evolution · 2024-11-01 · 4 citations

  articleOpen access1st authorCorresponding

  Generalist parasites seem to enjoy the clear ecological advantage of a greater chance to find a host, and genetic trade-offs are therefore often invoked to explain why specialists can coexist with or outcompete generalists. Here we develop an alternative perspective based on optimal foraging theory to explain why spatial clustering can favor specialists even without genetic trade-offs. Using analytical and simulation models inspired by bacteriophage, we examine the optimal use of two hosts, one yielding greater reproductive success for the parasite than the other. We find that a phage may optimally ignore the worse host when the two hosts are clustered together in dense, ephemeral patches. We model conditions that enhance or reduce this selective benefit to a specialist parasite and show that it is eliminated entirely when the hosts occur only in separate patches. These results show that specialists can be favored even when trade-offs are weak or absent and emphasize the importance of spatiotemporal heterogeneity in models of optimal niche breadth.

  PublisherDOI

• Demographic feedbacks during evolutionary rescue can slow or speed adaptive evolution

  Proceedings of the Royal Society B Biological Sciences · 2024-02-14 · 16 citations

  articleOpen access1st authorCorresponding

  Populations declining toward extinction can persist via genetic adaptation in a process called evolutionary rescue. Predicting evolutionary rescue has applications ranging from conservation biology to medicine, but requires understanding and integrating the multiple effects of a stressful environmental change on population processes. Here we derive a simple expression for how generation time, a key determinant of the rate of evolution, varies with population size during evolutionary rescue. Change in generation time is quantitatively predicted by comparing how intraspecific competition and the source of maladaptation each affect the rates of births and deaths in the population. Depending on the difference between two parameters quantifying these effects, the model predicts that populations may experience substantial changes in their rate of adaptation in both positive and negative directions, or adapt consistently despite severe stress. These predictions were then tested by comparison to the results of individual-based simulations of evolutionary rescue, which validated that the tolerable rate of environmental change varied considerably as described by analytical results. We discuss how these results inform efforts to understand wildlife disease and adaptation to climate change, evolution in managed populations and treatment resistance in pathogens.

  PublisherOA PDFDOI

• Relaxed selection can speed the evolution of complex adaptations

  bioRxiv (Cold Spring Harbor Laboratory) · 2024-07-09 · 8 citations

  preprintOpen access1st authorCorresponding

  Abstract Natural selection drives adaptive evolution and removes deleterious mutations; these effects are countervailing when a complex adaptation requires mutations that are initially deleterious when they arise, but beneficial in combination. While many models of this dynamic consider how genetic drift or other influences can aid valley crossing by weakening selection, we lack a general, analytical treatment of when relaxed selection might speed this type of adaptation. Here we use simulation and analysis to show that relaxed selection is generally favorable for valley-crossing when adaptive pathways require more than a single deleterious step. We also demonstrate that spatial heterogeneity in selection pressures could, by relaxing selection, allow populations to cross valleys much more rapidly than expected. These results relate to several applications of evolutionary theory to complex systems ranging from host-pathogen evolution to search algorithms in computer science.

  PublisherOA PDFDOI

• Bet-hedging via dispersal aids the evolution of plastic responses to unreliable cues

  Journal of Evolutionary Biology · 2023-05-24 · 5 citations

  articleOpen access1st authorCorresponding

  Abstract Adaptive plasticity is expected to evolve when informative cues predict environmental variation. However, plastic responses can be maladaptive even when those cues are informative, if prediction mistakes are shared across members of a generation. These fitness costs can constrain the evolution of plasticity when initial plastic mutants use of cues of only moderate reliability. Here, we model the barriers to the evolution of plasticity produced by these constraints and show that dispersal across a metapopulation can overcome them. Constraints are also lessened, though not eliminated, when plastic responses are free to evolve gradually and in concert with increased reliability. Each of these factors be viewed as a form of bet-hedging: by lessening correlations in the fates of relatives, dispersal acts as diversifying bet-hedging, while producing submaximal responses to a cue can be understood as a conservative bet-hedging strategy. While poor information may constrain the evolution of plasticity, the opportunity for bet-hedging may predict when that constraint can be overcome. Abstract Populations may make bad predictions when when using partially reliable cues to track changing environments (left). These mistakes can render plasticity deleterious (s < 0); right) when cue reliability is low, but dispersal among demes spreads out the effects of mistakes and allows the evolution of adaptive plasticity.

  PublisherOA PDFDOI

• Range expansion can promote the evolution of plastic generalism in coarse-grained landscapes

  Evolution Letters · 2023-12-14 · 2 citations

  articleOpen accessSenior author

  Phenotypic plasticity is one way for organisms to deal with variable environments through generalism. However, plasticity is not found universally and its evolution may be constrained by costs and other limitations such as complexity: the need for multiple mutational steps before the adaptation is realized. Theory predicts that greater experienced heterogeneity, such as organisms may encounter when spatial heterogeneity is fine-grained relative to dispersal, should favor the evolution of a broader niche. Here we tested this prediction via simulation. We found that, contrary to classical predictions, coarse-grained landscapes can be the most favorable for the evolution of plasticity, but only when populations encounter those landscapes through range expansion. During these range expansions, coarse-grained landscapes select for each step in the complex mutational pathway to plastic generalism by blocking the dispersal of specialists. These circumstances provide ecological opportunities for innovative mutations that change the niche. Our results indicate a new mechanism by which range expansion and spatially structured landscapes interact to shape evolution and reveal that the environments in which a complex adaptation has the highest fitness may not be the most favorable for its evolution.

  PublisherDOI

• Evolutionary rescue via niche construction: Infrequent construction can prevent post-invasion extinction

  Theoretical Population Biology · 2023-06-15 · 5 citations

  articleSenior author
  PublisherDOI

• Exploring the expanse between theoretical questions and experimental approaches in the modern study of evolvability

  Journal of Experimental Zoology Part B Molecular and Developmental Evolution · 2022-04-22 · 12 citations

  articleOpen access1st authorCorresponding

  Despite several decades of computational and experimental work across many systems, evolvability remains on the periphery with regards to its status as a widely accepted and regularly applied theoretical concept. Here we propose that its marginal status is partly a result of large gaps between the diverse but disconnected theoretical treatments of evolvability and the relatively narrower range of studies that have tested it empirically. To make this case, we draw on a range of examples-from experimental evolution in microbes, to molecular evolution in proteins-where attempts have been made to mend this disconnect. We highlight some examples of progress that has been made and point to areas where synthesis and translation of existing theory can lead to further progress in the still-new field of empirical measurements of evolvability.

  PublisherOA PDFDOI

Recent grants

• Limits to Evolvability Define the Maximal Sustainable Niche of Generalists

  NSF · $523k · 2022–2027

• Collaborative Research: Deep-sequencing analysis of edited metabolic pathways to uncover, model, and overcome the epistatic constraints upon optimization

  NSF · $180k · 2019–2021

• Collaborative Research: Deep-sequencing analysis of edited metabolic pathways to uncover, model, and overcome the epistatic constraints upon optimization

  NSF · $201k · 2017–2019

Frequent coauthors

• Joshua B. Plotkin

  University of Pennsylvania

  13 shared

• Remi Matthey‐Doret

  University of British Columbia

  9 shared

• Michael C. Whitlock

  University of British Columbia

  8 shared

• Christopher J. Marx

  University of Idaho

  8 shared

• Anna L. Hargreaves

  McGill University

  6 shared

• Paul E. Turner

  Yale University

  6 shared

• Günter P. Wagner

  Yale University

  6 shared

• Lon M. Chubiz

  University of Missouri–St. Louis

  4 shared

Awards & honors

• Nicholas Prize Thesis Award, 2009