Evolutionary Neuroscience and Behavior
Philipp Brand
From dancing honeybees to migrating birds who navigate star maps to our own distinct human capabilities, the astonishing diversity of behaviors across the tree of life has fascinated biologists for centuries. These endless variations are at the center of our research: We study behavior through the lens of the two main forces shaping organismal life on earth – evolution and ecology – to derive general principles underlying neural circuit function and diversification. By leveraging the power of natural variation, we aim to identify the core genetic and circuit mechanisms controlling behavior by isolating causal differences in the nervous system and their underlying genetic bases.
Our questions
- How does the nervous system encode behavioral variation?
- How does the environment shape behavioral evolution?
- How do microbes manipulate behaviors and their diversification?
Our approaches
Identifying the mechanisms of behavioral evolution requires a multidisciplinary approach integrating experimental ethology and genetics with circuit neuroscience in a comparative evolutionary framework. We are taking advantage of the diversity and neurogenetic toolkits in Drosophila fruit flies to investigate how the nervous system evolved changes in sensory processing of ecological and social cues underlying the diversification of species-specific mating behaviors.
Neuroscience
We leverage recent advances in genome editing techniques to translate the powerful neurogenetic toolkit available in the model organism Drosophila melanogaster to its more distant relatives. This allows us to compare neurons and neural circuits across species and form causal links between neuroanatomy, circuit function, and behavioral diversity using 2-photon in vivo functional brain imaging, neuroanatomy, and optogenetics tools.
Ethology
The power of these neurogenetic tools is contingent on the experimental tractability of behavior, which is unmatched in Drosophila. Their small size allows us to develop complex multiplexed experimental setups controlling the sensory environment of freely behaving or tethered flies, to study how diverse stimuli coordinately modulate behavior.
Genetics
We combine behavioral and neurogenetic approaches and integrate them with targeted single-cell neural transcriptomic profiling, population genetics, and QTL mapping, making use of the extensive genetic resources available across Drosophila, to elucidate how genetic variation and neural circuits contribute to behavioral evolution and the origin of species.
Selected Publications
DOI Brand P, Keller K, Coleman RT, Eghbali NB, Zylka S, Prieto-Godino LL, Ruta V (2025) Ecological cues orchestrate concerted courtship in a Drosophila host specialist. bioRxiv preprint
DOI Brand P, Hinojosa-Diaz I, Ayala R, Yurrita Obiols CL, Daigle M†, Eltz T & Ramirez SR (2020) The evolution of sexual signaling is linked to odorant receptor tuning in perfume-collecting orchid bees. Nature Communications 11:244.
DOI Brand P*, Robertson HM*, Lin W, Pothula R, Klingeman WE, Jurat-Fuentes JL & Johnson BR (2018) The origin of the odorant receptor gene family in insects. eLife 7:e38340