Tait Cheyenne, Kharva Hinal, Schubert Marco, Kritsch Daniel, Sombke Andy, Rybak Jürgen, Feder Jeffrey L, Olsson Shannon B
Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, USA.
Naturalist-Inspired Chemical Ecology, National Centre for Biological Sciences, Tata Institute of Fundamental Research, GKVK Campus, Bellary Road, Bangalore 560065, India.
Proc Biol Sci. 2021 Mar 31;288(1947):20210192. doi: 10.1098/rspb.2021.0192. Epub 2021 Mar 24.
Changes in behaviour often drive rapid adaptive evolution and speciation. However, the mechanistic basis for behavioural shifts is largely unknown. The tephritid fruit fly is an example of ecological specialization and speciation in action via a recent host plant shift from hawthorn to apple. These flies primarily use specific odours to locate fruit, and because they mate only on or near host fruit, changes in odour preference for apples versus hawthorns translate directly to prezygotic reproductive isolation, initiating speciation. Using a variety of techniques, we found a reversal between apple and hawthorn flies in the sensory processing of key odours associated with host fruit preference at the first olfactory synapse, linking changes in the antennal lobe of the brain with ongoing ecological divergence. Indeed, changes to specific neural pathways of any sensory modality may be a broad mechanism for changes in animal behaviour, catalysing the genesis of new biodiversity.
行为变化常常推动快速的适应性进化和物种形成。然而，行为转变的机制基础在很大程度上尚不清楚。实蝇是通过近期宿主植物从山楂转变为苹果而进行生态特化和物种形成的一个例子。这些果蝇主要利用特定气味来定位果实，并且由于它们只在宿主果实上或附近交配，对苹果与山楂气味偏好的变化直接转化为合子前生殖隔离，从而引发物种形成。通过使用各种技术，我们发现在第一个嗅觉突触处，苹果蝇和山楂蝇在与宿主果实偏好相关的关键气味的感官处理上发生了逆转，将大脑触角叶的变化与正在进行的生态分化联系起来。事实上，任何感觉模态的特定神经通路的变化可能是动物行为变化的一个广泛机制，催化新生物多样性的产生。
