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Unlike megabats, which rely on well-developed vision, microbats use ultrasonic echolocation to navigate and locate prey. To study ultrasound perception, here we compared the auditory cortices of microbats and megabats by constructing reference genomes and single-nucleus atlases for four species. We found that parvalbumin (PV)+neurons exhibited evident cross-species differences and could respond to ultrasound signals, whereas their silencing severely affected ultrasound perception in the mouse auditory cortex. Moreover, megabat PV+neurons expressed low levels of complexins (CPLX1–CPLX4), which can facilitate neurotransmitter release, while microbat PV+neurons highly expressed CPLX1, which improves neurotransmission efficiency. Further perturbation of Cplx1in PV+neurons impaired ultrasound perception in the mouse auditory cortex. In addition, CPLX1functioned in other parts of the auditory pathway in microbats but not megabats and exhibited convergent evolution between echolocating microbats and whales. Altogether, we conclude that CPLX1expression throughout the entire auditory pathway can enhance mammalian ultrasound neurotransmission.

Circulating H7N9 influenza viruses in live poultry markets continue to pose a threat to human health. Free-range poultry, one of the sources for these markets, are common in China as well as in many developing countries. Because the H9N2 virus could be a source of internal genes for the H7N9 virus, we conducted surveillance in free-range poultry and live poultry markets to study the evolution of H7N9 and H9N2 viruses in Eastern China. We found 28 samples positive for the H9N2 virus (a rate of 3.2%), but no positive samples for the H7N9 virus. Six representative H9N2 isolates were sequenced and analyzed, and the results showed that these viruses shared high nucleotide identities (99.0 to 100%) and were in a same branch in the phylogenetic trees. All these 6 viruses are closely clustered with Zhejiang H9N2 chicken isolates, and belonged to genotype G57, along with some novel H7N9 strains and H9N2 strains circulating in humans in China. We hope that surveillance of AIVs in free-range poultry will be strengthened for further identification more genetic diversity.