Royal Society Open Science最新文献

Caregivers often modulate their speech when interacting with infants, adapting a register that has been suggested to have attentional, affective and didactic purposes. The present preregistered study examined the longitudinal trajectories of a diverse range of acoustic features of infant-directed speech (IDS) and compared these with adult-directed speech (ADS), in Norwegian parents of 6- to 18-month-old infants. Sixty-nine families participated. Throughout five laboratory visits across one year, parents were recorded reading a picture-book to their infant (IDS) and an experimenter (ADS). The book was designed to tightly control for the linguistic content and context of speech between participants, timepoints and registers. Analyses of a total of 54 594 vowels and 22 958 phrases revealed, first, an overall effect of register: parents used higher pitch, wider pitch range, slower articulation rate, longer vowel duration and more variable and less distinct vowels in IDS than in ADS. Second, significant register-by-age interactions indicated that parents' IDS, compared with their ADS, featured wider pitch range, larger vowel space and shorter vowel duration in older as compared with younger infants, while pitch, articulation rate and vowel variability and distinctiveness remained relatively stable with age. Results are discussed in the context of the proposed functions of IDS.

Social and biological collectives exchange information through internal networks to function. Less studied is the quantity and variety of information transmitted. We characterize the information flow into organizations, primarily business firms. We measure online reading using a large dataset of articles accessed by employees across millions of firms. We measure and relate quantitatively three aspects: reading volume, variety and firm size. We compare volume with size, showing that firm sizes grow sublinearly with reading volume. This is like an economy of scale in information consumption that exaggerates the classic Zipf's law inequality for firm economics. We connect variety and volume to show that reading variety is limited. Firms above a threshold size read repetitively, consistent with the onset of a coordination problem between teams of employees in a simple model. Finally, we relate reading variety to size. The relationship is consistent with large firms that accumulate interests as they grow. We argue that this reflects structural constraints. Taking the scaling relations as a baseline, we show that excess reading is strongly correlated with returns and valuations. The results indicate how information consumption reflects internal structure, beyond individual employees, as is likewise important for collective information processing in other systems.

Over the last two decades, an emerging body of research has demonstrated that non-human animals exhibit the ability to combine context-specific calls into larger sequences. These structures have frequently been compared with language's syntax, whereby linguistic units are combined to form larger structures, and leveraged to argue that syntax might not be unique to language. Currently, however, the overwhelming majority of examples of call combinations are limited to simple sequences comprising just two calls which differ dramatically from the open-ended hierarchical structuring of the syntax found in language. We revisit this issue by taking a whole-repertoire approach to investigate combinatoriality in common marmosets (Callithrix jacchus). We use Markov chain models to quantify the vocal sequences produced by marmosets providing evidence for structures beyond the bigram, including three-call and even combinations of up to eight or nine calls. Our analyses of these longer vocal sequences are suggestive of potential further internal organization, including some amount of recombination, nestedness and non-adjacent dependencies. We argue that data-driven, whole-repertoire analyses are fundamental to uncovering the combinatorial complexity of non-human animals and will further facilitate meaningful comparisons with language's combinatoriality.

Voice preferences are an integral part of interpersonal interactions and shape how people connect with each other. While a large number of studies have investigated the mechanisms behind (speaking) voice attractiveness, very little research was dedicated to other types of vocalizations. In this Registered Report, we proposed to investigate voice preferences with an integrative approach. To this end, we used a newly recorded and validated stimulus set of contrasting vocalizations by 22 highly trained female singers speaking and singing the same material (in Brazilian Portuguese) in contrasting styles (sung as a lullaby, as a pop song or as an opera aria; and spoken aloud as if directed to an adult audience and as if directed to an infant). We asked 62 participants to rate these vocalizations in terms of how much they liked them; and we compared the amount of shared taste (that is, how much participants agreed in their preferences) across styles. We found highly idiosyncratic preferences across all styles. Our predictions concerning shared taste were not confirmed: although shared taste was higher for lullaby than for pop singing, it was unexpectedly higher for operatic than pop singing, and higher for infant-directed than adult-directed speech. Conversely, our prediction of limited consistency in average preferences for some singers across styles was confirmed, contradicting sexual selection-based ideas of singing and speaking as 'backup' signals of individual fitness. Our findings draw attention to the role of individual differences in voice preferences and highlight the need for a broader approach to understanding the underlying mechanisms of voice preferences. Stage 1 recommendation and review history: https://rr.peercommunityin.org/articles/rec?id=357. Stage 2 recommendation and review history: https://rr.peercommunityin.org/articles/rec?id=802.

The structural properties of the Saharan air layer (SAL) including chemical, morphological and optical properties were measured during the Saharan Aerosol Longrange TRansport and Aerosol Cloud interaction Experiment (SALTRACE- June/July 2013). Flight measurements were done from Cape Verde and the Caribbean. Changes happening with the chemical composition, mixing, shape and absorption of aerosol single particles (particle diameter range 0.5-3.0 µm) inside SAL during its transport are detailed. Dust-dominated SAL (relative number abundance >90%) and generally low mixing (<1% with sea-salt and sulphates) are observed at both locations. The change in shape (determined as aspect ratio (AR)) after transatlantic transport was statistically not significant. The iron oxide fraction, important for light absorption, contributed 6.0-6.8% to SAL dust. A lower amount of Fe oxides was observed in transported SAL, especially for the size range 0.5-1.5 µm. This reduction in Fe oxide content resulted in a 4% decrease (0.0046-0.0044) in dust imaginary refractive index and a 1% decrease in single scattering albedo (0.802-0.809) at 520 nm. Our work suggests including the size distribution of iron oxides and their particular behaviour in future experiment/model studies.

People have influenced Earth's biodiversity for millennia, including numerous introductions of domestic and wild species to islands. Here, we explore the origins and ecology of the Santa Catalina Island ground squirrel (SCIGS; Otospermophilus beecheyi nesioticus), one of only five endemic terrestrial mammals found on California's Santa Catalina Island. We synthesized all records of archaeological/palaeontological SCIGS, conducted radiocarbon dating and stable isotope analysis of the potentially earliest SCIGS remains and performed genetic analysis of modern SCIGS. Squirrels were not identified in island palaeontological deposits, but at least 12 island archaeological sites contain SCIGS bones, including some that are butchered or burned. All directly dated SCIGS bones are Late Holocene in age and younger than approximately 1290 cal BP. The first mitochondrial genome for modern Otospermophilus beecheyi and 15 modern SCIGS mitogenomes document at least one introduction of squirrels. Stable isotope data indicate variable SCIGS diets and potential subsidies from marine environments to terrestrial plants consumed by some individuals. We cannot rule out a natural overwater dispersal, but the earliest SCIGS remains post-date the earliest evidence for people by several millennia and, along with other lines of evidence, support a human-assisted translocation of squirrels during the Late Holocene. These data illustrate the important role of Indigenous people in shaping and enhancing island biodiversity and ecology around the world.

Habitat loss and forest fragmentation are often linked to increased pathogen transmission, but the extent to which habitat isolation and landscape connectivity affect disease dynamics through movement of disease vectors and reservoir hosts has not been well examined. Tick-borne diseases are the most prevalent vector-borne diseases in the United States and on the West Coast, Ixodes pacificus is one of the most epidemiologically important vectors. We investigated the impacts of habitat fragmentation on pathogens transmitted by I. pacificus and sought to disentangle the effects of wildlife communities and landscape metrics predictive of pathogen diversity, prevalence and distribution. We collected pathogen data for four co-occurring bacteria transmitted by I. pacificus and measured wildlife parameters. We also used spatial data and cost-distance analysis integrating expert opinions to assess landscape metrics of habitat fragmentation. We found that landscape metrics were significant predictors of tick density and pathogen prevalence. However, wildlife variables were essential when predicting the prevalence and distribution of pathogens reliant on wildlife reservoir hosts for maintenance. We found that landscape structure was an informative predictor of tick-borne pathogen richness in an urban matrix. Our work highlights the implications of large-scale land management on human disease risk.

Airway constriction and blockage in obstructive lung diseases cause ventilation heterogeneity and create barriers to effective drug deposition. Established computational particle-deposition models have not accounted for these impacts of disease. We present a new particle-deposition model that calculates ventilation based on the resistance of each airway, such that ventilation responds to airway constriction. The model incorporates distal airway constrictions representative of cystic fibrosis, allowing us to investigate the resulting impact on patterns of deposition. Unlike previous models, our model predicts how constrictions affect deposition in airways throughout the lungs, not just in the constricted airways. Deposition is reduced in airways directly distal and proximal to constrictions. When constrictions are clustered together, central-airways deposition can increase significantly in regions away from constrictions, but distal-airways deposition in those regions remains largely unchanged. We use our model to calculate lung clearance index (LCI), a clinical measure of ventilation heterogeneity, after applying constrictions of varying severities in one lobe. We find an increase in LCI coinciding with significantly reduced deposition in the affected lobe. Our results show how the model provides a framework for development of computational tools that capture the impacts of airway disease, which could significantly affect predictions of regional dosing.

Spatial learning is vital in foraging ecology. Many hymenopteran insects are adept spatial foragers that rely on visual cues contained within broader wide-field scenes for central place foraging from a central nest. By contrast, for butterflies, which lack central nest sites, visual cue use during spatial foraging is less understood. Heliconius butterflies, however, exhibit stable nocturnal roosts, strong site fidelity and a sophisticated capacity for spatial navigation. This study furthers our understanding of Heliconius spatial learning by testing whether H. erato can associate a spatially informative visual cue with artificial feeders. We explored the relative importance of a visual local landmark compared with broader, wide-field visual cues, through experiments with (i) a fixed rewarded feeder with a local landmark; (ii) a mobile rewarded feeder with the landmark as the sole reliable cue; (iii) the same setup while blocking visual access to external landscape features. Our data suggest that Heliconius butterflies learn static feeder locations without relying on a local individual landmark. Instead, we suggest they integrate broader landscape and celestial cues. This suggests that Heliconius butterflies and central place foraging hymenopterans likely share similar visual navigation strategies, using wide-field, low-resolution views rather than focusing on specific individual landmarks.

The acoustic repertoires of long-finned pilot whales (Globicephala melas) in the Mediterranean Sea are poorly understood. This study aims to create a catalogue of calls, analyse acoustic parameters, and propose a classification tree for future research. An acoustic database was compiled using recordings from the Alboran Sea, Gulf of Lion and Ligurian Sea (Western Mediterranean Basin) between 2008 and 2022, totalling 640 calls. Using a deep neural network, the calls were clustered based on frequency contour similarities, leading to the identification of 40 distinct call types defining the local population's vocal repertoire. These categories encompass pulsed calls with varied complexities, from simplistic to highly intricate structures comprising multiple elements and segments. This study marks the initial documentation of the vocal catalogue of long-finned pilot whales in the Mediterranean Sea. Subsequent research should delve deeper into this multifaceted communication system and explore its potential linkages with social structures.