Behavioural Ecology Group, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
Research Laboratory for Stereology and Neuroscience, Bispebjerg-Frederiksberg Hospital, Copenhagen, Denmark.
Brain Behav Evol. 2021;96(1):37-48. doi: 10.1159/000517489. Epub 2021 Jul 20.
Correlations between differences in animal behavior and brain structures have been used to infer function of those structures. Brain region size has especially been suggested to be important for an animal's behavioral capability, controlled by specific brain regions. The oval nucleus of the mesopallium (MO) is part of the anterior forebrain vocal learning pathway in the parrot brain. Here, we compare brain volume and total number of neurons in MO of three parrot species (the peach-fronted conure, Eupsittula aurea, the peach-faced lovebird, Agapornis roseicollis, and the budgerigar, Melopsittacus undulatus), relating the total neuron numbers with the vocal response to playbacks of each species. We find that individuals with the highest number of neurons in MO had the shortest vocal latency. The peach-fronted conures showed the shortest vocal latency and largest number of MO neurons, the peach-faced lovebird had intermediary levels of both, and the budgerigar had the longest latency and least number of neurons. These findings indicate the MO nucleus as one candidate region that may be part of what controls the vocal capacity of parrots.
动物行为差异与大脑结构之间的相关性已被用于推断这些结构的功能。大脑区域的大小尤其被认为对动物的行为能力很重要，由特定的大脑区域控制。中脑的卵圆核（MO）是鹦鹉大脑前脑发声学习途径的一部分。在这里，我们比较了三种鹦鹉物种（桃面爱情鸟、桃面爱情鸟和虎皮鹦鹉）的 MO 脑体积和总神经元数量，将总神经元数量与每种物种对回放的发声反应相关联。我们发现，MO 中神经元数量最多的个体具有最短的发声潜伏期。桃面爱情鸟表现出最短的发声潜伏期和最大数量的 MO 神经元，桃面爱情鸟具有中等水平的潜伏期和 MO 神经元数量，虎皮鹦鹉的潜伏期最长，MO 神经元数量最少。这些发现表明 MO 核是控制鹦鹉发声能力的候选区域之一。
