Variability is fundamental to behavior, and is patterned across time, individual, and species

Individual differences in behavior are a substrate for animal evolution, the essence of personality and individuality, and part of the mystery of who is afflicted by a psychological disorder and who is not. Our research aims to discover the neural circuitry and genetic and evolutionary mechanisms underlying behavioral variation using novel behavioral instruments and computational ethology. We are particularly curious about behavioral differences that exist even when genes and environment are matched, as well as ecologically important behaviors in natural contexts.

Research

Data

Two-panel figure showing computer output from machine learning experiments: top panel has six bars with bands of assorted colors, bottom panel has lines with peaks in grey, blue, red, and green.

Automated behavioral classification

Classifications of spontaneous behavior, assigned by human investigators and machine learning algorithms

Four-panel figure showing fluorescent images of fly body with neurons illuminated in turquoise, and black and white images with structures outlined in yellow.

Neural circuit for handedness

Neural circuit elements (PB-FB-No projection neurons) regulating behavioral diversity

Line graph with lines intersecting to form a horizontal triangle, transitioning from gray to pink.

Phototactic choice histories

Individual flies display divergent light preferences over time; color indicates statistical significance

Lines with peaks in grey, blue, green, and red, with two distinct lines in green and red showing more dramatic peaks.

Leg and fly motion

Fictive motion of a fly running on a ball in the LegTracker and the x- and y- coordinates of its legs, over time

Two-panel figure showing predicted evolutionary strategies across climate and geography. Top panel is a heat map, bottom panel is a map of the United States showing temperature.

Evolutionary phase space

Predicted optimal evolutionary strategies underlying behavioral diversity, varying across climate and geography

Two side by side schematics showing several multicolored circles interlinked by lines and arrows in various directions.

Behavioral ethograms

A visual representation of the Markov transition rates between various modes of spontaneous fly behavior - determined by the LegTracker

Horizontal bar graph comparing phototactic personality between four species. Bars represent different species, with lengths indicating relative phototactic behavior.

Variation across species

The white clover weevil and three Drosophila species vary across strain and species in how much phototactic personality they have

Two-panel figure: top is a heat map with blue background and patterns of yellow, orange, and red. Bottom shows three lines with peaks in orange, blue, and grey.

Effect of weather on behavior

Predicted fly population dynamics and phototactic behavior dynamics as influenced by real world weather conditions from 2008

Circular schematic with trails of flies in orange, green, and blue. Trails follow specific paths around the circle, with axes labeled p/2, 2p, 3p/2, and p.

Exploration metric

Schematic of a metric to characterize spontaneous exploration of a circular arena

Microscopy images of GABAergic neurons in the fan-shaped body (red) and ellipsoid body (turquoise). The fan-shaped body shows denser turquoise concentration.

GABAergic circuitry

GABAergic neurons in the fan-shaped body and ellipsoid body, densely packed neural circuits mediating locomotor decision-making

A figure with six panels: four with shaded checkerboards, two with numbered circles linked by lines. Top right is two stacked diamonds, bottom right a parallelogram.

Injury and gait

Leg motion transition matrices and gait schematics before (top) and after (bottom) amputation of a fly's fore leg

Three “exploratory paths” that appear as large clusters of smaller lines. The blue and cyan paths appear nearly identical, the red with fewer lines along the bottom segment.

Injury and exploration

Exploratory paths, segmented and registered, before (blue) amputation of a leg, immediately after (red), and after a few recovery days (cyan)

Fluorescent image of a drosophila leg, showing bright green patches where protein is expressed.

Leg proprioceptive organ

Green fluorescent protein expressed in the femur chordotonal organ, a sensory structure encoding proprioceptive feedback

Models

Neurons regulating phototaxis

Neuronal elements implicated in the control of the polarity, plasticity and variability of phototactic responses

Origin of phototactic personality

Developmental timing and genetic regulators of phototactic personality

Spatial decision-making circuit

A model of an azimuthal decision-making circuit in the central complex of the fly brain

Fly life history

Basic fly life history: birth as an egg, metamorphosis, adulthood and egg-laying, various ways of dying

Gait recovery after injury

Stages of exploratory walking behavior following injury and the genes required to transition between these stages

Inventions

Y-maze Array

Measures locomotor handedness and exploratory activity of individual flies, 120 at a time

SlowPhotoBox

Measures the resting shade vs. light light preference of individual flies, 30 at a time

FlyVac Module

A behavioral T-maze built into an circuit board, uses infrared beams to detect when a individual fly chooses to go toward or away from a light source

FlyVac

Coordinates 32 modules to autonomously measure the light preference of individual flies, many times each

LegTracker

An instrument for recording the position of all 6 of a fly's legs, in real time, at 80Hz