Research

“Development is the natural history of genes.”
– MP Scott, Cell 2000

Researchers in the Streelman lab use the cichlid fish model to address fundamental questions in ecology and evolution. We are fascinated by context-dependent processes like embryonic development, the regeneration of organs and complex behavior. Context-dependency is interesting because it reveals new rules of biological systems that are not necessarily operational during homeostasis. For instance, recent results suggest that stem-like cells in the brain may tune the evolution of male social behavior.

We raise cichlids from Lake Malawi in custom fish facilities at Georgia Tech. We invent automated assays to quantify behavior, we sequence genomes and the transcriptomes of cells, and we collaborate with computational scientists, engineers and colleagues working in zebrafish, mouse and human. Members of the lab are keen to learn new things by working together, compelled by mechanism and comparative approaches.

Brain development and evolution:
Brain diversity evolves via differences in patterning
Competing signals drive telencephalon diversity
Behavioral evolution contributes to hindbrain diversification among Lake Malawi cichlid fish
Genome-enabled discovery of evolutionary divergence in brains and behavior

Tooth/jaw development and evolution:
Integration and evolution of the cichlid mandible: the molecular basis of alternate feeding strategies
An ancient gene network is co-opted for teeth on old and new jaws
A quiescent cell population replenishes mesenchymal stem cells to drive accelerated growth in mouse incisors
Coevolutionary patterning of teeth and taste buds
Developmental plasticity of epithelial stem cells in tooth and taste bud renewal
Single cell RNA sequencing reveals deep homology of dental cell types across vertebrates

Evolution of behavior:
Cellular profiling of a recently-evolved social behavior
The genomic substrate for adaptive radiation in African cichlid fish
Behavior-dependent cis regulation reveals genes and pathways associated with bower building in cichlid fishes
Applying gene regulatory network logic to the evolution of social behavior
Ecotype differences in aggression, neural activity and behaviorally relevant gene expression in cichlid fish
Exploratory behaviour is associated with microhabitat and evolutionary radiation in Lake Malawi cichlids
Automated measurement of long-term bower behaviors in Lake Malawi cichlids using depth sensing and action recognition