Development and Sex Shape the Brain: New Atlas Reveals Insights into Fruit Fly Neurobiology

Researchers at the University of Oxford have created a high-resolution molecular atlas of the adult Drosophila melanogaster (common fruit fly) brain, uncovering how neurons retain a record of their developmental origins. A parallel study demonstrates how these developmental programs are selectively reused and modified by sex to generate male and female behavioral diversity. Together, these studies, published in Cell Genomics, provide a new framework for understanding brain architecture, its evolution and functional specialization.

A Detailed Atlas of Neuron Diversity

Led by Professor Stephen Goodwin’s group in Oxford’s Department of Physiology, Anatomy and Genetics (DPAG), the research offers an unprecedented view of neuronal diversity. By integrating multiple single-cell RNA sequencing datasets, the researchers achieved 10-fold coverage of the Drosophila central brain, capturing transcriptional information for nearly every individual neuron.

The team surprisingly found that the genetic diversity of neurons is greater than previously thought, with many cell types represented by only a single neuron per hemisphere. Their analyses suggest that transcriptomic and anatomical identities are complementary and equally informative for defining neuronal types, bridging developmental and systems-level perspectives.

“Our results show that the adult brain carries a molecular record of how it was built,” said Professor Goodwin. “We can now see that the diversity of neurons, and therefore of behaviors, emerges from a simple developmental logic based on lineage, timing, and selective differentiation.”

How Sex Shapes Shared Brain Blueprints

The companion study extends these principles to sexual dimorphism, revealing that male and female brains utilize the same developmental templates in different ways. Rather than separate male and female circuits, sex differences arise through selective neuronal survival within shared lineages. Female-biased neurons tend to be born early, while male-biased neurons emerge later, indicating that sex leverages distinct developmental windows to shape behavior.

“This shows how evolution can create new behavioral capabilities without rebuilding the brain from scratch,” said lead author Dr. Erin Allen. “Sex doesn’t reinvent the wiring; it tweaks when and which neurons persist.”

Tools and Implications for Neuroscience

These findings redefine the developmental logic of the fly brain and provide essential parameters for computational and systems neuroscience. By revealing how molecular and anatomical classifications intersect, the atlas offers a foundation for modeling brain organization and function.

The Goodwin group has created a user-friendly website featuring interactive visualizations of the atlases referenced in these studies, allowing researchers to explore the data directly.

Publication Details:

• Aaron M. Allen et al, A high-resolution atlas of the brain predicts lineage and birth order underlying neuronal identity, Cell Genomics (2025).
• Aaron M. Allen et al, Differential neuronal survival defines a novel axis of sexual dimorphism in the Drosophila brain, Cell Genomics (2026).

Journal Information: Cell Genomics

Source: University of Oxford