A role for ultrasonic vocalisation in social communication and divergence of natural populations of the house mouse (Mus musculus domesticus)

It has long been known that rodents emit signals in the ultrasonic range, but their role in social communication and mating is still under active exploration. While inbred strains of house mice have emerged as a favourite model to study ultrasonic vocalisation (USV) patterns, studies in wild animals and natural situations are still rare. We focus here on two wild derived mouse populations. We recorded them in dyadic encounters for extended periods of time to assess possible roles of USVs and their divergence between allopatric populations. We have analysed song frequency and duration, as well as spectral features of songs and syllables. We show that the populations have indeed diverged in several of these aspects and that USV patterns emitted in a mating context differ from those emitted in same sex encounters. We find that females vocalize not less, in encounters with another female even more than males. This implies that the current focus of USVs being emitted mainly by males within the mating context needs to be reconsidered. Using a statistical syntax analysis we find complex temporal sequencing patterns that could suggest that the syntax conveys meaningful information to the receivers. We conclude that wild mice use USV for complex social interactions and that USV patterns can diverge fast between populations

A humanized version of Foxp2 affects ultrasonic vocalization in adult female and male mice

Abstract The transcription factor FoxP2 is involved in setting up the neuronal circuitry for vocal learning in mammals and birds and is thought to have played a special role in the evolution of human speech and language. It has been shown that an allele with a humanized version of the murine Foxp2 gene changes the ultrasonic vocalization of mouse pups compared to pups of the wild-type inbred strain. Here we tested if this humanized allele would also affect the ultrasonic vocalization of adult female and male mice. In a previous study, in which only male vocalization was considered and the mice were recorded under a restricted spatial and temporal regime, no difference in adult vocalization between genotypes was found. Here, we use a different test paradigm in which both female and male vocalizations are recorded in extended social contact. We found differences in temporal, spectral and syntactical parameters between the genotypes in both sexes, and between sexes. Mice carrying the humanized Foxp2 allele were using higher frequencies and more complex syllable types than mice of the corresponding wildtype inbred strain. Our results support the notion that the humanized Foxp2 allele has a differential effect on mouse ultrasonic vocalization. As mice carrying the humanized version of the Foxp2 gene show effects opposite to those of mice carrying disrupted or mutated alleles of this gene, we conclude that this mouse line represents an important model for the study of human speech and language evolution

Genomic resources for wild populations of the house mouse, Mus musculus and its close relative Mus spretus

WOS: 000390231600001PubMed ID: 27622383Wild populations of the house mouse (Mus musculus) represent the raw genetic material for the classical inbred strains in biomedical research and are a major model system for evolutionary biology. We provide whole genome sequencing data of individuals representing natural populations of M. m. domesticus (24 individuals from 3 populations), M. m. helgolandicus (3 individuals), M. m. musculus (22 individuals from 3 populations) and M. spretus (8 individuals from one population). We use a single pipeline to map and call variants for these individuals and also include 10 additional individuals of M. m. castaneus for which genomic data are publically available. In addition, RNAseq data were obtained from 10 tissues of up to eight adult individuals from each of the three M. m. domesticus populations for which genomic data were collected. Data and analyses are presented via tracks viewable in the UCSC or IGV genome browsers. We also provide information on available outbred stocks and instructions on how to keep them in the laboratory.Max-Planck Society; DFG [HA 3139/4-1]; ERC [322564]; contract-research-project for the Bundeswehr Medical Service [M/SABX/005]This work was mostly financed by institutional resources of the Max-Planck Society, a DFG grant to B.H. and M.T. (HA 3139/4-1) and an ERC grant to D.T. (NewGenes, 322564). We thank Sonja Ihle, Susanne Krochter, Ruth Rottscheidt for contributing to collecting animals in the wild and our animal care takers for active involvement of optimizing the scheme for wild mouse keeping. The initial analysis of mice from Afghanistan was funded by contract-research-project for the Bundeswehr Medical Service M/SABX/005. We thank Bastian Pfeifer for help with software package PopGenome, Leslie Turner for discussion and Daniel M. Hooper and Trevor Price for helpful comments on the manuscript. D.T. had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis

Comparison of the gap segmentation gene hunchback between Drosophila melanogaster and Drosophila virilis reveals novel modes of evolutionary change.

We have cloned and sequenced a large portion of the hunchback (hb) locus from Drosophila virilis. Comparison with the Drosophila melanogaster hb sequence shows multiple strong homologies in the upstream and downstream regions of the gene, including most of the known functional parts. The coding sequence is highly conserved within the presumptive DNA-binding finger regions, but more diverged outside of them. The regions of high divergence are correlated with regions which are rich in short direct repeats (regions of high 'cryptic simplicity'), suggesting a significant influence of slippage-like mechanisms in the evolutionary divergence of the two genes. Staining of early D.virilis embryos with an hb antibody reveals conserved and divergent features of the spatial expression pattern at blastoderm stage. It appears that the basic expression pattern, which serves as the gap gene function of hb, is conserved, while certain secondary expression patterns, which have separate functions for the segmentation process, are partly diverged. Thus, both slippage driven mutations in the coding region, which are likely to occur at higher rates than point mutations and the evolutionary divergence of secondary expression patterns may contribute to the evolution of regulatory genes

Spectrograms of the 13 syllable types.

<p>Spectrograms were generated with 256(FFT) using the software Selena (Department of Animal Physiology, University of Tübingen; Germany). For abbreviations see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0097244#pone-0097244-t002" target="_blank">table 2</a>.</p

Discriminant function analysis of syllable parameters in the different social contexts.

<p>Scatter plots are separated by sex and population. Arrows indicate the direction of the three parameters with the strongest influence on the separation of the data: slope, jumps, turns; plus and minus indicate a positive or negative change of the parameter in the arrow's direction; for the loadings of these and the other parameters see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0097244#pone-0097244-t005" target="_blank">table 5</a>. Abbreviations and colours as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0097244#pone-0097244-g004" target="_blank">Figure 4</a>.</p

All temporal and spectral parameters used in the main analysis. For each group of mice the mean (+/− standard deviation) is given.

(1)<p>start frequency, frequency slope (calculated as change of frequency in kHz per ms), minimum frequency, frequency band (calculated as change of frequency in kHz per ms) and COG of frequency (COG = Centre of gravity, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0097244#s2" target="_blank">Methods</a> section <i>Sound analysis</i> for calculation).</p