哈佛大学Hopi E. Hoekstra小组在研究中取得进展。他们提出了Peromyscus小鼠物种特异性防御行为的神经基础。这一研究成果于2025年7月23日发表在国际顶尖学术期刊《自然》上。

在这里，课题组人员发现鹿鼠的两个姊妹物种（Peromyscthem属）对同样的隐现刺激表现出不同的反应：位于植被密集的栖息地的Peromysus maniculatus主要是逃跑，而开阔的野地专家Peromyscthem polionotthem则会短暂地冻结。这种差异源于物种特有的逃避阈值，在很大程度上与环境无关，并且可以由视觉和听觉威胁刺激触发。通过免疫组织化学和电生理记录，该研究组发现尽管视觉威胁激活了两种动物的上丘，但背侧导水管周围灰质（dPAG）在驾驶行为中的作用不同。然而，在马甲棘猴中，dPAG的活性与奔跑速度有关，而在脊髓灰质炎棘猴中，dPAG的神经活性与运动（包括视觉触发的逃跑）的相关性很差。

此外，dPAG神经元的光遗传学激活引起了P. maniculatus的加速，而在P. polionotus中则没有，并且它们在隐现刺激时的化学遗传学抑制延迟了P. maniculatus的逃逸发生，以与P. polionotus相匹配。该课题组将物种特异性的逃避阈值追溯到外周感觉神经元下游的中央回路节点，将生态相关的行为差异定位于哺乳动物大脑的特定区域。

据了解，躲避掠食者迫在眉睫的威胁对动物的生存至关重要。有效的防御策略是不同的，即使是在关系密切的物种之间。然而，这种物种特异性行为的神经基础仍然知之甚少。

附：英文原文

Title: The neural basis of species-specific defensive behaviour in Peromyscus mice

Author: Baier, Felix, Reinhard, Katja, Nuttin, Bram, Sans-Dublanc, Arnau, Liu, Chen, Tong, Victoria, Murmann, Julie S., Wierda, Keimpe, Farrow, Karl, Hoekstra, Hopi E.

Issue&Volume: 2025-07-23

Abstract: Evading imminent threat from predators is critical for animal survival. Effective defensive strategies can vary, even between closely related species. However, the neural basis of such species-specific behaviours remains poorly understood1,2,3,4. Here we find that two sister species of deer mice (genus Peromyscus)5 show different responses to the same looming stimulus: Peromyscus maniculatus, which occupies densely vegetated habitats, predominantly escapes, whereas the open field specialist, Peromyscus polionotus, briefly freezes. This difference arises from species-specific escape thresholds, is largely context-independent, and can be triggered by both visual and auditory threat stimuli. Using immunohistochemistry and electrophysiological recordings, we find that although visual threat activates the superior colliculus in both species, the role of the dorsal periaqueductal grey (dPAG) in driving behaviour differs. Whereas dPAG activity scales with running speed in P. maniculatus, neural activity in the dPAG of P. polionotus correlates poorly with movement, including during visually triggered escape. Moreover, optogenetic activation of dPAG neurons elicits acceleration in P. maniculatus but not in P. polionotus, and their chemogenetic inhibition during a looming stimulus delays escape onset in P. maniculatus to match that of P. polionotus. Together, we trace species-specific escape thresholds to a central circuit node, downstream of peripheral sensory neurons, localizing an ecologically relevant behavioural difference to a specific region of the mammalian brain.

DOI: 10.1038/s41586-025-09241-2

Source: https://www.nature.com/articles/s41586-025-09241-2