Mastodawn

The power of #Drosophila genetics to study neuronal evolution:

"We then modified Drosophila retinas to have butterfly-like transcription factor expression, causing recruitment of an additional R7. The two R7s make independent stochastic choices, like butterflies, leading to three stochastically distributed ommatidial types instead of two."

And then they show how the excess of neurons that would otherwise die or repeat existing circuit motifs is repurposed to accommodate the extra photoreceptors, configuring retinal circuits like in the buttefly.

"Sensory receptor expansion and neural accommodation in butterfly color vision", Gao et al. 2025.

#neuroscience #NeuralEvolution #NeuroEvo

Albert Cardona May 3, 2025

"Comparative single-cell transcriptomic atlases of drosophilid brains suggest glial evolution during ecological adaptation", Lee et al. 2025 (Richard Benton's lab)
https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.3003120

#neuroscience #Drosophila #glia #evolution #NeuroEvo

Comparative single-cell transcriptomic atlases of drosophilid brains suggest glial evolution during ecological adaptation

How do diverse brain cells change over evolution? By comparing single-cell transcriptomic atlases from ecologically-distinct drosophilid species, this work identifies changes in the composition and gene expression patterns of different cell types, revealing higher divergence in glia than neurons.

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Albert Cardona Jul 3, 2023

And of course lifestyle, or rather, ecological niche specialisation, tilts the vision-olfaction trade off, here in wasps:

“Differential investment in visual and olfactory brain regions is linked to the sensory needs of a wasp social parasite and its host”, by Rozanski et al. 2021 https://onlinelibrary.wiley.com/doi/full/10.1002/cne.25242

This work compared the eusocial wasp Polistes dominula with its obligate social parasite Polistes sulcifer.

#NeuroEvo #neuroscience #entomology #Hymenoptera #wasplove #wasps #Polistes

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Albert Cardona Jul 3, 2023

The tradeoff between vision and olfaction has been studied in flies. There’s a strain of Drosophila melanogaster that’s been reared in the dark for decades: the so-called “dark flies”. Here, the authors examine the effect of rearing “dark flies” in the light for 1 and for 65 generations, and observe how brain regions for vision are boosted even within 1 generation:

“Back to the light, coevolution between vision and olfaction in the “Dark-flies” (Drosophila melanogaster)”
Özer & Carle 2020 https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0228939

#neuroscience #DarkFlies #Drosophila #evolution #NeuroEvo

Back to the light, coevolution between vision and olfaction in the “Dark-flies” (Drosophila melanogaster)

Trade-off between vision and olfaction, the fact that investment in one correlates with decreased investment in the other, has been demonstrated by a wealth of comparative studies. However, there is still no empirical evidence suggesting how these two sensory systems coevolve, i.e. simultaneously or alternatively. The “Dark-flies” (Drosophila melanogaster) constitute a unique model to investigate such relation since they have been reared in the dark since 1954, approximately 60 years (~1500 generations). To observe how vision and olfaction evolve, populations of Dark-flies were reared in normal lighting conditions for 1 (DF1G) and 65 (DF65G) generations. We measured the sizes of the visual (optic lobes, OLs) and olfactory (antennal lobes, ALs) primary centres, as well as the rest of the brain, and compared the results with the original and its genetically most similar strain (Oregon flies). We found that, whereas the ALs decreased in size, the OLs (together with the brain) increased in size in the Dark-flies returned back to the light, both in the DF1G and DF65G. These results experimentally show that trade-off between vision and olfaction occurs simultaneously, and suggests that there are possible genetic and epigenetic processes regulating the size of both optic and antennal lobes. Furthermore, although the Dark-flies were able to mate and survive in the dark with a reduced neural investment, individuals being returned to the light seem to have been selected with reinvestment in visual capabilities despite a potential higher energetic cost.

Albert Cardona Jun 6, 2023

"Phylogenetic tracing of midbrain-specific regulatory sequences suggests single origin of eubilaterian brains", by Schuster and Hirth, 2023 https://www.science.org/doi/10.1126/sciadv.ade8259

A genetic signature of bilateral animals with brains, including "a genetic boundary separating the rostral from caudal nervous systems, demonstrated for the metameric brains of annelids, arthropods, and chordates and the asegmental cycloneuralian and urochordate brain"

In other words, the genetic toolkit of the ancestor of both protostomes (arthropods, nematodes, molluscs and annelids) and deuterostomes (echinoderms and vertebrates) – the eubilaterian.

https://www.science.org/doi/10.1126/sciadv.ade8259

#neuroscience #DevBiol #EvoDevo #NeuroEvo #evolution

Albert Cardona Jan 27, 2023

Today is the last day to apply to the neuro-evo conference at #HHMIJanelia!

Apply here: https://www.janelia.org/you-janelia/conferences/neuro-evo-a-comparative-approach-to-cracking-circuit-function-iii

Dates: May 15-18, 2023.

#NeuroEvo #Janelia #HHMI #conference #neuroscience #connectomics #DevBio #EvoDevo

https://mathstodon.xyz/@albertcardona/109405695524270512

Neuro-Evo: A Comparative Approach to Cracking Circuit Function III | Janelia Research Campus

Organizers Albert Cardona, MRC Laboratory of Molecular Biology David Stern, Janelia Research Campus/HHMI Maria Tosches, Columbia University Invited Participants Tom Baden, University of Sussex Alison Barker, MPI for Brain Research Kevin Briggman, MPI for Neurobiology of Behavior Pawel Burkhardt, University of Bergen Mitya Chklovskii, Flatiron Institute Josie Clowney,

Albert Cardona Jan 16, 2023

Neuro-evo conference at HHMI Janelia on May 15-18, 2023.

Application deadline: January 27, 2023

Apply here: https://www.
janelia.org/you-janelia/confer
ences/neuro-evo-a-comparative-approach-to-cracking-circuit-function-iii

"this meeting will bring together neuroscientists working on a broad diversity of animal models in an effort to compare circuits across phyla as a means to crack their function."

#NeuroEvo #Janelia #HHMI #conference #science #neuroscience #DevBio #connectomics #connectome

Albert Cardona Nov 25, 2022

Neuro-evo conference at HHMI Janelia on May 15-18, 2023. Join us for the 3rd edition!

Application deadline: Jan 27 (11:59 p.m. EST) 2023.

Apply here: https://www.janelia.org/you-janelia/conferences/neuro-evo-a-comparative-approach-to-cracking-circuit-function-iii

"The third instalment of this meeting will once again bring together neuroscientists working on a broad diversity of animal models in an effort to compare circuits across phyla as a means to crack their function."

#NeuroEvo #Janelia #HHMI #conference #science #academia #neuroscience #DevBio #connectomics #connectome

Neuro-Evo: A Comparative Approach to Cracking Circuit Function III | Janelia Research Campus

Albert Cardona Nov 21, 2022

Neuro-evo conference at HHMI Janelia on May 15-18, 2023. Join us for the third edition!

Application deadline: Jan 27 (11:59 p.m. EST) 2023.

Apply here: https://www.janelia.org/you-janelia/conferences/neuro-evo-a-comparative-approach-to-cracking-circuit-function-iii

"Historically, with the study of the most convenient animal models —from the giant axon of the squid and the lobster's stomatogastric circuits to Aplysia's synapses and C. elegans' circuits — neuroscientists revealed some of the operating principles of the nervous system, which were then found to apply broadly across phyla. The third instalment of this meeting will once again bring together neuroscientists working on a broad diversity of animal models in an effort to compare circuits across phyla as a means to crack their function."

#NeuroEvo #Janelia #HHMI #conference #science #academia #neuroscience #DevBio #connectomics #connectome