Speech is a crowning achievement of human evolution, the skill that separates us from every other animal. So, it would stand to reason that evolving this capability required some enormous leap in brain complexity. A study published today in Nature suggests otherwise.
Alston鈥檚 singing mouse (Scotinomys teguina), a small rodent from the cloud forests of Central America, produces loud, elaborate songs humans can hear across a room. These mice can sing solo but often perform rapid-fire duets with split-second timing. Among all mammals, it鈥檚 one of the closest parallels to the turn-taking of human conversations.
A team at 黑料吃瓜资源 (CSHL) wanted to know what changed inside this animal鈥檚 brain to make singing possible. The answer was surprisingly simple. The singing mouse didn鈥檛 evolve a bigger brain, new brain regions, or new categories of neural connections. Instead, evolution roughly tripled the number of neurons that connect the brain鈥檚 mouth-movement control center with just two target regions. One is the cortex that controls hearing. The other is a midbrain structure that controls vocalizations for a variety of species, including humans. The rest of the brain wiring is essentially identical to that of an ordinary lab mouse!
, a grad student in the Banerjee lab, traced the differences using a molecular barcoding technique developed at CSHL by Professor Anthony Zador. This allowed the team to map thousands of individual cells across the whole brain. 鈥淲hen you look at singing mice and lab mice side by side, their brains are almost indistinguishable,鈥� Isko said. 鈥淭丑别 differences only show up when you trace where individual neurons send signals.鈥�
During both the songs of singing mice and the everyday communications of ordinary lab mice, neurons send signals from the brain鈥檚 orofacial motor cortex (OMC) to the auditory cortical region and midbrain periaqueductal gray. About three times as many of these neural projections occur in the brains of singing mice.
鈥淵ou might expect that evolving a whole new means of vocal communication would require a significant reorganization of brain circuitry,鈥� said Associate Professor Arkarup Banerjee. 鈥淚nstead, we found a couple of targeted changes to existing wiring patterns. Our approach gives the field a playbook. To understand how new behaviors evolve, find closely related species with big behavioral differences and start by mapping the wiring at high-resolution.鈥�
The findings have implications far beyond mice. At some point since humans split from chimps millions of years ago, our higher brain regions gained enough control over vocalization to produce speech. The singing mouse鈥檚 two amplified brain regions are central to human vocal circuits. Additionally, brain-imaging research has identified stronger connections between similar motor and auditory areas in humans than in other primates. The singing mouse may be replaying a version of the evolutionary trick that put our ancestors on the road to language.
鈥淭丑别 fact that these changes are relatively simple and targeted raises an exciting possibility,鈥� said Zador. 鈥淚f only a few specific wiring changes separate singing mice from lab mice, we might be able to engineer those changes ourselves. Could we make a lab mouse sing?鈥�
Could tomorrow鈥檚 pop stars see competition in unexpected places? Maybe not, but the discovery could someday provide new tools for speech therapy while addressing a question central to the human experience. How did language emerge?
Written by: Jen A. Miller | [email protected] | 516-367-8455
Funding
NIH BRAIN Initiative, Searle Scholars Program, Esther A. & Joseph Klingenstein Fund, Simons Foundation, McKnight Foundation, NSF Graduate Research Fellowship Program
Citation
Isko, E.C. et al., 鈥淪pecific expansion of motor cortical projections in a singing mouse鈥�, Nature, May 6, 2026. DOI:
Core Facilites
鈥�MAPseq (Multiplexed Analysis of Projections by Sequencing) and BARseq (barcoded anatomy resolved by sequencing) are novel high-throughput methods for brain mapping and spatial transcriptomics unique to CSHL. The facility provides reagents, protocols, and consultations, and helps users process tissue samples for high-throughput sequencing at various resolutions.鈥� 鈥� Director Ching Zhan, Ph.D.
鈥淭丑别 Microscopy Core Facility provides training, consultation, experimental design and technical assistance to investigators at CSHL in widefield, spinning disk laser scanning or point laser scanning confocal fluorescence microscopy, and super-resolution microscopy. In addition, the Microscopy Shared Resource provides customized state-of-the-art optical imaging and quantitative image analysis applications to support a wide range of scientific endeavors.鈥� 鈥� Director Erika Wee, Ph.D.