The fly's nervous system consists of the brain plus the ventral nerve cord, and both are known to differ considerably between male and female.
[5] The available connectomes show only chemical synapses - other forms of inter-neuron communication such as gap junctions or neuromodulators are not represented.
These numbers are not independent, since both the brain and the nerve cord contain portions of the several thousand ascending and descending neurons that run through the neck of the fly.
[12] Reconstructions of larger regions soon followed, including a column of the medulla,[13] also in the visual system of the fruit fly, and the alpha lobe of the mushroom body.
[14] In 2017 a paper introduced an electron microscopy image stack of the whole adult female brain at synaptic resolution.
[15][16] In 2020, a dense connectome of half the central brain of Drosophila was released,[17] along with a web site that allows queries and exploration of this data.
In parallel, a consensus cell type atlas for the Drosophila brain was published, produced based on this 'FlyWire' connectome and the prior 'hemibrain'.
In 2022, a group of scientists mapped the motor control circuits of the ventral nerve cord of a female fruit fly using electron microscopy.
Using this representation, Winding et al found that the larval brain neurons could be clustered into 93 different types, based on connectivity alone.
One of the main uses of the Drosophila connectome is to understand the neural circuits and other brain structure that gives rise to behavior.