Evolution of olfactory circuits in insects.

TitleEvolution of olfactory circuits in insects.
Publication TypeJournal Article
Year of Publication2020
AuthorsZhao, Z, McBride, CS
JournalJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
Date Published2020 May
KeywordsAnimals, Behavior, Animal, Biological Evolution, Brain, Drosophila, Evolution, Molecular, Moths, Neural Pathways, Odorants, Olfactory Perception, Olfactory Receptor Neurons, Smell, Species Specificity

<p>Recent years have seen an explosion of interest in the evolution of neural circuits. Comparison of animals from different families, orders, and phyla reveals fascinating variation in brain morphology, circuit structure, and neural cell types. However, it can be difficult to connect the complex changes that occur across long evolutionary distances to behavior. Luckily, these changes accumulate through processes that should also be observable in recent time, making more tractable comparisons of closely related species relevant and complementary. Here, we review several decades of research on the evolution of insect olfactory circuits across short evolutionary time scales. We describe two well-studied systems, Drosophila sechellia flies and Heliothis moths, in detailed case studies. We then move through key types of circuit evolution, cataloging examples from other insects and looking for general patterns. The literature is dominated by changes in sensory neuron number and tuning at the periphery-often enhancing neural response to odorants with new ecological or social relevance. However, changes in the way olfactory information is processed by central circuits is clearly important in a few cases, and we suspect the development of genetic tools in non-model species will reveal a broad role for central circuit evolution. Moving forward, such tools should also be used to rigorously test causal links between brain evolution and behavior.</p>

Alternate JournalJ Comp Physiol A Neuroethol Sens Neural Behav Physiol
PubMed ID31984441
PubMed Central IDPMC7192870
Grant ListR00 DC012069 / DC / NIDCD NIH HHS / United States
DP2 AI144246 / AI / NIAID NIH HHS / United States