Exploring Levels of Interspecies Interaction: Expectations, Knowledge, and Empathy in Human-Dog Relationships.

This exploratory study examines the complex dynamics of human-dog relationships and their impact on interspecies communication. Twelve human-dog dyads were studied using narrative interviews to explore how people perceive their relationships with their dogs. In addition, the dyads engaged in a cooperative task to observe interaction dynamics during everyday activities. This study shows that individual expectations frame interactions and that traditional notions of dog ownership are evolving into more family-like relationships. Effective communication relies on a nuanced mix of verbal and non-verbal cues, with empathy emerging as a fundamental element guiding these interactions. Our findings underline the profound influence of human expectations, knowledge and empathy on communication with dogs. They also highlight the critical role of compatibility between human and dog dyads, and emphasize that such compatibility is a key determinant of satisfaction in interspecies relationships. These findings contribute to a deeper understanding of how human factors modulate communication and satisfaction in human-animal interactions.

α-Pyrone mediates quorum sensing through the conservon system in Nocardiopsis sp.

Actinobacteria produce a plethora of bioactive secondary metabolites that are often regulated by quorum-sensing signaling molecules via specific binding to their cognate TetR-type receptors. Here, we identified monocyclic α-pyrone as a new class of actinobacterial signaling molecules influencing quorum sensing process in Nocardiopsis sp. LDBS0036, primarily evidenced by a significant reduction in the production of phenazines in the pyrone-null mutant compared to the wild-type strain. Exogenous addition of the α-pyrone can partially restore the expression of some pathways to the wild strain level. Moreover, a unique multicomponent system referred to as a conservon, which is widespread in actinobacteria and generally contains four or five functionally conserved proteins, may play an important role in detecting and transmitting α-pyrone signals in LDBS0036. We found the biosynthetic gene clusters of α-pyrone and their associated conservon genes are highly conserved in Nocardiopsis, indicating the widespread prevalence and significant function of this regulate mechanism within Nocardiopsis genus. Furthermore, homologous α-pyrones from different actinobacterial species were also found to mediate interspecies communication. Our results thus provide insights into a novel quorum-sensing signaling system and imply that various modes of bacterial communication remain undiscovered.

The polymicrobial pathogenicity of Porphyromonas gingivalis.

Accumulating microbiome data and mechanistic studies in vitro and in vivo have refined our understanding of the oral microbiota as a functionally integrated polymicrobial community. Emergent properties of these communities are driven to a large extent by interspecies communication which can be based on physical association, secreted small molecules or nutritional exchange. Porphyromonas gingivalis is a consensus periodontal pathogen; however, virulence is only expressed in the context of a polymicrobial community. Multivalent fimbriae mediate attachment to other oral species which can initiate a distinct transcriptional program in both constituents of the binding pair. P. gingivalis also responds to small molecules and nutritional cues produced by partner organisms. Physiological interdependence forms the basis of complex networks of cooperating organisms which begin to resemble an organismal entity exhibiting a spectrum of pathogenic potential.

Research status and challenges of plant-derived exosome-like nanoparticles.

In recent years, there has been an increasing number of related studies on exosomes. Most studies have focused on exosomes derived from mammals, confirming the important role that exosomes play in cell communication. Plants, as a natural ingredient, plant-derived exosomes have been confirmed to have similar structures and functions to mammalian-derived exosomes. Plant-derived exosome-like nanoparticles (PELNs) are lipid bilayer membrane nanovesicles containing bioactive constituents such as miRNA, mRNA, protein, and lipids obtained from plant cells, that can participate in intercellular communication and mediate transboundary communication, have high bioavailability and low immunogenicity, are relatively safe, and have been shown to play an important role in maintaining cell homeostasis and preventing, and treating a variety of diseases. In this review, we describe the biogenesis, isolation and purification methods, structural composition, stability, safety, function of PELNs and challenges. The functions of PELNs in anti-inflammatory, antioxidant, antitumor and drug delivery are mainly described, and the status of research on exosome nanoparticles of Chinese herbal medicines is outlined. Overall, we summarized the importance of PELNs and the latest research results in this field and provided a theoretical basis for the future research and clinical application of PELNs.

A Relaxed Horse-A Relaxed Client? An Experimental Investigation of the Effects of Therapy Horses' Stress on Clients' Stress, Mood, and Anxiety.

Equine-assisted therapies are becoming increasingly popular for addressing physical and psychological disabilities in clients. The role of the horse's welfare in equine-assisted service receives increasing attention in research. Several studies have shown that horses are able to perceive human emotions and respond to human stress responses. However, no research has yet looked at the other side of the coin-whether and how humans perceive and react to equine stress levels during equine-assisted services. To fill this gap in the research, we employed a within-subjects design, in which horse-naïve participants had a standardized interaction with both an experimentally stressed horse and an experimentally relaxed horse. We assessed physiological indicators of stress (heart rate, heart rate variability, and salivary cortisol) in participants and horses, as well as psychological indicators of stress (state anxiety and positive and negative affect) in participants. Although our stress and relaxation manipulations were successful (indicated by horses' physiological indicators of stress), we did not find any difference in the participants' physiological or psychological indicators of stress between the interaction with a stressed and the interaction with a relaxed horse. Together with results from previous studies, this suggests that humans cannot intuitively recognize the (physiological) stress level of horses, which has important implications for effective communication and bonding between humans and horses and for the safety of equine activities.

Use of Augmentative Interspecies Communication devices in animal language studies: A review.

Countless discussions have been generated by the animal language studies, specifically those utilizing mechanical interfaces, termed here Augmentative Interspecies Communication (AIC) devices (e.g., lexigrams; magnetic chips; keyboards). Overall, three concerns dominate the field: (1) claims that AIC device using animals manifest linguistic skills remain nebulous, and simpler alternative mechanisms have been proposed (e.g., associative learning); (2) such methodology may be unsuitable as some theorize AIC device interfaces are not sufficiently ecologically relevant to foster meaningful use; (3) data may be considered dubious due to potential cueing from experimenters and lack of systematicity in reporting training and performance. Despite such controversy-which eventually led to the field's deterioration around the last quarter of the twentieth century-this research also saw important successes, such as improvements in captive animal welfare, the outcomes of which hold promise for future interspecies communication work. This article is categorized under: Linguistics > Evolution of Language.

Current understanding of plant-derived exosome-like nanoparticles in regulating the inflammatory response and immune system microenvironment.

Natural compounds are widely used to prevent and treat various diseases due to their antioxidant and anti-inflammatory effects. As a kind of promising natural compound, plant-derived exosome-like nanoparticles (PELNs) are extracted from multivesicular bodies of various edible plants, including vegetables, foods, and fruits, and mainly regulate the cellular immune response to pathogen attacks. Moreover, PELNs could remarkably interfere with the dynamic imbalance between pro-inflammatory and anti-inflammatory effects, facilitating to maintain the homeostasis of cellular immune microenvironment. PELNs may serve as a better alternative to animal-derived exosomes (ADEs) owing to their widespread sources, cost-effectiveness, and easy accessibility. PELNs can mediate interspecies communication by transferring various cargoes such as proteins, lipids, and nucleic acids from plant cells to mammalian cells. This review summarizes the biogenesis, composition, and classification of exosomes; the common separation, purification, and characterization methods of PELNs, the potential advantages of PELNs over ADEs; and the anti-inflammatory and immunomodulatory functions of PELNs in various diseases including colitis, cancer, and inflammation-associated metabolic diseases. Additionally, the future perspectives of PELNs and the challenges associated with their clinical application are discussed.

Algae communication, conspecific and interspecific: the concepts of phycosphere and algal-bacteria consortia in a photobioreactor (PBR).

Microalgae in the wild often form consortia with other species promoting their own health and resource foraging opportunities. The recent application of microalgae cultivation and deployment in commercial photobioreactors (PBR) so far has focussed on single species of algae, resulting in multi-species consortia being largely unexplored. Reviewing the current status of PBR ecological habitat, this article argues in favor of further investigation into algal communication with conspecifics and interspecifics, including other strains of microalgae and bacteria. These mutualistic species form the 'phycosphere': the microenvironment surrounding microalgal cells, potentiating the production of certain metabolites through biochemical interaction with cohabitating microorganisms. A better understanding of the phycosphere could lead to novel PBR configurations, capable of incorporating algal-microbial consortia, potentially proving more effective than single-species algal systems.

Biological Functions and Cross-Kingdom Host Gene Regulation of Small RNAs in Lactobacillus plantarum-Derived Extracellular Vesicles.

Extracellular vesicle-mediated transfer of microRNAs is a novel mode of cell-to-cell genetic transmission. Extracellular vesicles produced by microbes have been shown to contain significant quantities of physiologically active molecules such as proteins, lipids, and RNA, which could be transported to host cells and play a key role in both inter-kingdom signaling and physiological responses. In this study, we identified sRNAs by sequencing small RNAs (sRNAs) from Lactobacillus plantarum-derived extracellular vesicles (LDEVs) and detected the expression levels of vesicular sRNAs using quantitative reverse transcription-polymerase chain reaction (RT-PCR), which demonstrated the presence of microRNA-sized RNAs (msRNAs) within these vesicles. We chose sRNA71, a highly expressed msRNA, for further investigation, predicted its potential target genes for the human genome, and indicated that it could be translocated into mammalian cells. The biological functions of this sRNA71 were subsequently explored through cellular proteomics, western blot, and luciferase reporter assay. According to the findings, transfection with synthetic sRNA71 mimics substantially reduced Tp53 expression in HEK293T cells and suppressed the gene expression through binding to the 3' UTR of Tp53 mRNA. In conclusion, it is hypothesized that microbial-derived extracellular vesicles serve as carriers of functional molecules such as sRNAs, which play an essential role in regulating microbial-host communication.

Microbiota and Oral Cancer as A Complex and Dynamic Microenvironment: A Narrative Review from Etiology to Prognosis.

A complex balanced equilibrium of the bacterial ecosystems exists in the oral cavity that can be altered by tobacco smoking, psychological stressors, bad dietary habit, and chronic periodontitis. Oral dysbiosis can promote the onset and progression of oral squamous cell carcinoma (OSCC) through the release of toxins and bacterial metabolites, stimulating local and systemic inflammation, and altering the host immune response. During the process of carcinogenesis, the composition of the bacterial community changes qualitatively and quantitatively. Bacterial profiles are characterized by targeted sequencing of the 16S rRNA gene in tissue and saliva samples in patients with OSCC. Capnocytophaga gingivalis, Prevotella melaninogenica, Streptococcus mitis, Fusobacterium periodonticum, Prevotella tannerae, and Prevotella intermedia are the significantly increased bacteria in salivary samples. These have a potential diagnostic application to predict oral cancer through noninvasive salivary screenings. Oral lactic acid bacteria, which are commonly used as probiotic therapy against various disorders, are valuable adjuvants to improve the response to OSCC therapy.

Do bovids evolve hindquarter markings for anti-predation?

Conspicuous coloration in animals serves many functions such as anti-predation. Anti-predation strategies include motion dazzle and flash behavior. Motion dazzle markings can reduce the probability of being preyed on because the predators misjudge their movement. In flash behavior, prey demonstrate conspicuous cue while fleeing; the predators follow them; however, the prey hide their markings and the predators assume that the prey has vanished. To investigate whether bovids use conspicuous hindquarter markings as an anti-predatory behavior, we undertook phylogenetically controlled analyses to explore under what physiological characteristics and environmental factors bovids might have this color pattern. The results suggested that rump patches and tail markings were more prevalent in bovids living in larger-sized groups, which supports the hypothesis of intraspecific communication. Moreover, we observed the occurrence of conspicuous white hindquarter markings in bovids having smaller body size and living in larger groups, suggesting a motion dazzle function. However, the feature of facultative exposing color patterns (flash markings) was not associated with body size, which was inconsistent with predictions and implied that bovids may not adopt this as an anti-predator strategy. It was concluded that species in bovids with conspicuous white hindquarter markings adopt motion dazzle as an anti-predation strategy while fleeing and escaping from being prey on.

The Relevance of Human Whistled Languages for the Analysis and Decoding of Dolphin Communication.

Humans use whistled communications, the most elaborate of which are commonly called "whistled languages" or "whistled speech" because they consist of a natural type of speech. The principle of whistled speech is straightforward: people articulate words while whistling and thereby transform spoken utterances by simplifying them, syllable by syllable, into whistled melodies. One of the most striking aspects of this whistled transformation of words is that it remains intelligible to trained speakers, despite a reduced acoustic channel to convey meaning. It constitutes a natural traditional means of telecommunication that permits spoken communication at long distances in a large diversity of languages of the world. Historically, birdsong has been used as a model for vocal learning and language. But conversely, human whistled languages can serve as a model for elucidating how information may be encoded in dolphin whistle communication. In this paper, we elucidate the reasons why human whistled speech and dolphin whistles are interesting to compare. Both are characterized by similar acoustic parameters and serve a common purpose of long distance communication in natural surroundings in two large brained social species. Moreover, their differences - e.g., how they are produced, the dynamics of the whistles, and the types of information they convey - are not barriers to such a comparison. On the contrary, by exploring the structure and attributes found across human whistle languages, we highlight that they can provide an important model as to how complex information is and can be encoded in what appears at first sight to be simple whistled modulated signals. Observing details, such as processes of segmentation and coarticulation, in whistled speech can serve to advance and inform the development of new approaches for the analysis of whistle repertoires of dolphins, and eventually other species. Human whistled languages and dolphin whistles could serve as complementary test benches for the development of new methodologies and algorithms for decoding whistled communication signals by providing new perspectives on how information may be encoded structurally and organizationally.

Nonhuman and Nonhuman-Human Communication: Some Issues and Questions.

Deciphering nonhuman communication - particularly nonhuman vocal communication - has been a longstanding human quest. We are, for example, fascinated by the songs of birds and whales, the grunts of apes, the barks of dogs, and the croaks of frogs; we wonder about their potential meaning and their relationship to human language. Do these utterances express little more than emotional states, or do they convey actual bits and bytes of concrete information? Humans' numerous attempts to decipher nonhuman systems have, however, progressed slowly. We still wonder why only a small number of species are capable of vocal learning, a trait that, because it allows for innovation and adaptation, would seem to be a prerequisite for most language-like abilities. Humans have also attempted to teach nonhumans elements of our system, using both vocal and nonvocal systems. The rationale for such training is that the extent of success in instilling symbolic reference provides some evidence for, at the very least, the cognitive underpinnings of parallels between human and nonhuman communication systems. However, separating acquisition of reference from simple object-label association is not a simple matter, as reference begins with such associations, and the point at which true reference emerges is not always obvious. I begin by discussing these points and questions, predominantly from the viewpoint of someone studying avian abilities. I end by examining the question posed by Premack: do nonhumans that have achieved some level of symbolic reference then process information differently from those that have not? I suggest the answer is likely "yes," giving examples from my research on Grey parrots (Psittacus erithacus).

A Review of the Model/Rival (M/R) Technique for Training Interspecies Communication and Its Use in Behavioral Research.

In this paper, I will review the Model/Rival (M/R) technique that has been used to establish interspecies communication with Grey parrots (Psittacus erithacus). I will describe the original format developed by Todt, the relationship to other forms of observational learning outlined by other researchers, and the adaptations that I devised. I will describe how my undergraduate trainers and I isolated the various components that constitute the technique and explain how each is necessary, but how only the combination of all components is sufficient for successful implementation-and how improper implementation can lead to failure. I will briefly summarize the results of proper implementation-including the importance of interspecies communication itself as a technique for studying animal cognition.

Frequency modulation of rattlesnake acoustic display affects acoustic distance perception in humans.

The estimation of one's distance to a potential threat is essential for any animal's survival. Rattlesnakes inform about their presence by generating acoustic broadband rattling sounds.1 Rattlesnakes generate their acoustic signals by clashing a series of keratinous segments onto each other, which are located at the tip of their tails.1-3 Each tail shake results in a broadband sound pulse that merges into a continuous acoustic signal with fast-repeating tail shakes. This acoustic display is readily recognized by other animals4,5 and serves as an aposematic threat and warning display, likely to avoid being preyed upon.1,6 The spectral properties of the rattling sound1,3 and its dependence on the morphology and size of the rattle have been investigated for decades7-9 and carry relevant information for different receivers, including ground squirrels that encounter rattlesnakes regularly.10,11 Combining visual looming stimuli with acoustic measurements, we show that rattlesnakes increase their rattling rate (up to about 40 Hz) with decreasing distance of a potential threat, reminiscent of the acoustic signals of sensors while parking a car. Rattlesnakes then abruptly switch to a higher and less variable rate of 60-100 Hz. In a virtual reality experiment, we show that this behavior systematically affects distance judgments by humans: the abrupt switch in rattling rate generates a sudden, strong percept of decreased distance which, together with the low-frequency rattling, acts as a remarkable interspecies communication signal. VIDEO ABSTRACT.

Interspecies RNA Interactome of Pathogen and Host in a Heritable Defensive Strategy.

Communication with bacteria deeply impacts the life history traits of their hosts. Through specific molecules and metabolites, bacteria can promote short- and long-term phenotypic and behavioral changes in the nematode Caenorhabditis elegans. The chronic exposure of C. elegans to pathogens promotes the adaptive behavior in the host's progeny called pathogen-induced diapause formation (PIDF). PIDF is a pathogen avoidance strategy induced in the second generation of animals infected and can be recalled transgenerationally. This behavior requires the RNA interference machinery and specific nematode and bacteria small RNAs (sRNAs). In this work, we assume that RNAs from both species co-exist and can interact with each other. Under this principle, we explore the potential interspecies RNA interactions during PIDF-triggering conditions, using transcriptomic data from the holobiont. We study two transcriptomics datasets: first, the dual sRNA expression of Pseudomonas aeruginosa PAO1 and C. elegans in a transgenerational paradigm for six generations and second, the simultaneous expression of sRNAs and mRNA in intergenerational PIDF. We focus on those bacterial sRNAs that are systematically overexpressed in the intestines of animals compared with sRNAs expressed in host-naïve bacteria. We selected diverse in silico methods that represent putative mechanisms of RNA-mediated interspecies interaction. These interactions are as follows: heterologous perfect and incomplete pairing between bacterial RNA and host mRNA; sRNAs of similar sequence expressed in both species that could mimic each other; and known or predicted eukaryotic motifs present in bacterial transcripts. We conclude that a broad spectrum of tools can be applied for the identification of potential sRNA and mRNA targets of the interspecies RNA interaction that can be subsequently tested experimentally.

Inflammation Mediators Regulate the Microbiota Resistance to Adverse Factors.

We studied the effects of IL-1ß, IL-8, TNFα, and prostaglandin E2α in concentrations typically observed in health and during inflammation on the growth of vaginal microbiota and its resistance to factors inhibiting the synthesis of proteins, nucleic acids, and peptidoglycans. An increase in the cytokine levels, characteristic of inflammation, inhibits the growth of Lactobacillus population and improves its resistance to adverse factors. The growth of the population of opportunistic microorganisms (S. aureus, E. coli) is stimulated under these conditions, while their resistance to adverse factors decreases. Hence, it seems that the cytokines regulate the behavior of the host cells and of its bacterial symbionts.

Activation of paulomycin production by exogenous γ-butyrolactone signaling molecules in Streptomyces albidoflavus J1074.

The interspecies communication roles of γ-butyrolactones (GBLs) have been described for a long time but are still poorly understood. Herein, we analyzed more than 1000 Streptomyces strains and noticed a big quantitative gap between the strains with GBL biosynthetic genes and the strains with GBL receptor genes, which implies the wide-spread of GBLs as interspecies signals in Streptomyces and their great potential in the activation of silent natural product gene clusters. Streptomyces albidoflavus J1074, which has one GBL receptor gene but no GBL biosynthetic gene, was chosen as a target to study the possible interspecies communication roles of GBLs. At first, the GBL biosynthetic genes from Streptomyces coelicolor M145 were expressed in S. albidoflavus J1074, which enabled the S. albidoflavus strains to synthesize Streptomyces coelicolor butanolides (SCBs) and activated the production of paulomycins. Further studies showed that this activation process requires the participation of the GBL receptor gene XNR_4681. The results suggest that the expression of exogenous GBL biosynthetic genes can modulate the metabolisms of GBL non-producing strains, and this regulation role might be meaningful for silent gene cluster activation in Streptomyces. At final, we synthesized racemic-SCB2 and tried to simplify the activation process by adding SCB2 directly to S. albidoflavus J1074, which unfortunately failed to induce paulomycin production.

Effects of size and personality on social learning and human-directed behaviour in horses (Equus caballus).

Due to our long history of living in close association with horses, these animals are suggested to have enhanced skills in understanding and communicating with humans. Today, horses have become important to humans for sport and leisure and their understanding of human behaviour and their human-directed behaviour are therefore of great importance. In this study, we investigated 22 horses in a human contact-seeking experiment where they were presented with an unsolvable problem and a detour experiment with a human demonstrator. The unsolvable problem consisted of pieces of carrot in a closed bucket and the detour resembled the shape of V. Additionally, personality traits of the participating horses were assessed. Interestingly, the full-sized horses (N = 11) showed more human-related behaviours when presented with an unsolvable problem compared to before the carrots were made unreachable (p = 0.033), while the ponies (N = 11) did not. However, neither the full-sized horses nor the ponies were significantly more successful in the detour after human demonstrations than in control trials. When comparing the two experiments, we found the task-oriented behaviour in the detour test to positively correlate with human proximity and eye contact-seeking behaviour towards humans during the unsolvable problem in the contact-seeking test. Interestingly, again this was only true for the full-sized horses (p < 0.05) and not for the ponies. From the horse personality questionnaire results, the traits excitability and anxiousness revealed strong negative correlations with human-directed behaviour in the contact-seeking experiment (p < 0.05). Hence, size (full-sized horse/pony) and personality influenced the human-related behaviours of the horses and we suggest a future focus on these aspects to deepen our understanding of human-horse communication.

Animal language studies: What happened?

The extent to which nonhuman animals can learn actual human language is a controversial question, but many nonhuman species have acquired elements of a two-way communication system that is, and was, sophisticated enough to enable its use in evaluating cognitive capacities. This article is a personal view of the history of these animal language studies.