We study how plastic (flexible) and evolutionary responses to environmental variation shape behavioral and morphological traits. We explore a variety of research questions, approaches, and organisms to better understand how plasticity and genetic proccesses contribute to biological diversification.

Evolution of mating systems

Geographic variation in phenotype

Social experience and mating behavior




Social plasticity

Genetic structure of traits within and among populations

Temperature variation and mating behavior

Inter-species interactions

Predator-prey interactions

Predator cues and plasticity


Enchenopa binotata treehoppers are small (1/2 cm) plant-feeding insects that sing to one another prior to mating. However, the songs they produce do not travel through the air, but instead through plant stems via tiny vibrations. Using specialized equipment (laser vibrometers, accelerometers), you can listen to these songs. You can also use vibrational playbacks to sing back to them. In our lab, we are primarily interested in how male song and female mate preferences differ across variable social and ecological environments.

Some major projects on treehoppers include:

i. Social plasticity - Several social factors influence female mate preferences and male singing behavior, including variation in the presence of conspecifics and heterospecifics, density, and neighborhood composition.

ii. Genetic structure of traits - Patterns of genetic variation and covariation in female preferences and male signals vary across species and populations. The specific patterns should influence patterns of phenotypic diversity.

iii. Temperature variation and mating behavior - Temperature influences almost every major biological process, and mating behavior is no exception. We currently have a multi-year project investigating genetic and plastic factors influencing patterns of mating in treehoppers across temperatures and latitudes.

E. binotata in a social group in the field.


Leiobunine harvestmen of North America (commonly known as daddy longlegs) form a clade with high diversity in mating. In some species, long drawn-out mating interactions involve struggles between the male and female. In other species, mating involves a quick, cordial exchange. We study diversity in behavior within a phylogenetic context using a combination of field work and experimentation in the lab. Some major projects on harvestmen include:

i. Evolution of mating behavior - we are interested in understanding how and why different morphological traits (e.g. male body size, armament size) predict the outcome of mating interactions in different species in the clade.

ii. Geographic variation in mating behavior - we are conducting a long-term project studying geographic variation in mating behavior in several species within the clade.

iii. Social influences on mating behavior - the types of competitors and potential mates  should influence patterns of mating success across individuals. We are researching how different social situations influence mating dynamics.


Predators can influence prey by consuming them, but also by influencing the behaviors prey exhibit. For example, male wolf spiders  delay courtship and male treehoppers will delay flight when predation risk is high. We continue to expand our studies of predator-prey interactions in other systems. Some major questions include:

i. Predator cues and plasticity - organisms often change their behavioral patterns when they encounter cues from potential predators. We are interested in the potential evolutionary consequences of this type of plasticity.

ii. Predator-prey interactions - We are interested in predators detect and hunt prey, as well as the evolution of anti-predator mechanisms in prey. We are particularly interested in how these processes unfold in vibrationally communicating and vibrationally sensitive arthropods.

Male leiobunum harvestmen eating a juvenile of a different species

iii. Inter-species interactions - Plastic responses to the threat of predation are often phenotype-specific. We explore the patterns of plasticity in relationship to phenotype across a variety of arthropods.

Mailing: Department of Biology, Saint Louis University

              3507 Laclede Ave. Saint Louis, MO 63103

Email:    Contact Dr. Fowler-Finn

Lab: 143B Macelwane Hall

Office: 324 Macelwane Hall

 2015  K Fowler-Finn, all rights reserved. Last updated 10/2015