scholarly journals Natural visual cues eliciting predator avoidance in fiddler crabs

2011 ◽  
Vol 278 (1724) ◽  
pp. 3584-3592 ◽  
Author(s):  
Jochen Smolka ◽  
Jochen Zeil ◽  
Jan M. Hemmi

To efficiently provide an animal with relevant information, the design of its visual system should reflect the distribution of natural signals and the animal's tasks. In many behavioural contexts, however, we know comparatively little about the moment-to-moment information-processing challenges animals face in their daily lives. In predator avoidance, for instance, we lack an accurate description of the natural signal stream and its value for risk assessment throughout the prey's defensive behaviour. We characterized the visual signals generated by real, potentially predatory events by video-recording bird approaches towards an Uca vomeris colony. Using four synchronized cameras allowed us to simultaneously monitor predator avoidance responses of crabs. We reconstructed the signals generated by dangerous and non-dangerous flying animals, identified the cues that triggered escape responses and compared them with those triggering responses to dummy predators. Fiddler crabs responded to a combination of multiple visual cues (including retinal speed, elevation and visual flicker) that reflect the visual signatures of distinct bird and insect behaviours. This allowed crabs to discriminate between dangerous and non-dangerous events. The results demonstrate the importance of measuring natural sensory signatures of biologically relevant events in order to understand biological information processing and its effects on behavioural organization.

2020 ◽  
Author(s):  
Abhishek Mukherjee ◽  
Soibam Shyamchand Singh ◽  
Dipanjan Ray ◽  
Partha Raghunathan ◽  
Arpan Banerjee

In daily lives, speech perception requires binding of spatiotemporally disjoint auditory and visual cues. On the other hand, functional segregation and integration are the two complementary mechanisms that capture brain information processing. Here, we demonstrate using fMRI recordings that subjective perceptual experience of multisensory speech stimuli is dependent on a homeostatic balance of segregation and integration mechanisms. Previous reports conceptualized posterior superior temporal sulcus as the key brain region for binding signals from multiple sensory streams. However, we report an enhancement of segregated information processing in distributed brain regions, defined as the perceptual binding network. The seed-based whole brain functional connectivity of each node in this network was anti-correlated with higher propensity for illusory perception. Interestingly, the perceptual binding network was anti-correlated with other intrinsic brain networks, such as dorsal attention and default mode networks during cross-modal perception. The pattern disappeared for people who rarely reported the illusory perception, further strengthening the hypothesis of homeostatic balance. The cognitive theories of Bayesian causal inference and predictive coding hypothesis could explain the balance of segregative and integrative mechanisms during cross-modal perception.


2014 ◽  
Vol 64 (Pt_2) ◽  
pp. 689-691 ◽  
Author(s):  
Yoon-Seong Jeon ◽  
Kihyun Lee ◽  
Sang-Cheol Park ◽  
Bong-Soo Kim ◽  
Yong-Joon Cho ◽  
...  

EzEditor is a Java-based molecular sequence editor allowing manipulation of both DNA and protein sequence alignments for phylogenetic analysis. It has multiple features optimized to connect initial computer-generated multiple alignment and subsequent phylogenetic analysis by providing manual editing with reference to biological information specific to the genes under consideration. It provides various functionalities for editing rRNA alignments using secondary structure information. In addition, it supports simultaneous editing of both DNA sequences and their translated protein sequences for protein-coding genes. EzEditor is, to our knowledge, the first sequence editing software designed for both rRNA- and protein-coding genes with the visualization of biologically relevant information and should be useful in molecular phylogenetic studies. EzEditor is based on Java, can be run on all major computer operating systems and is freely available from http://sw.ezbiocloud.net/ezeditor/.


2018 ◽  
Author(s):  
Julia Marchetti ◽  
Alexander Miguel Monzon ◽  
Silvio C.E. Tosatto ◽  
Gustavo Parisi ◽  
María Silvina Fornasari

AbstractInter-residue contacts determine the structural properties for each conformer in the ensembles describing the native state of proteins. Structural constraints during evolution could then provide biologically relevant information about the conformational ensembles and their relationship with protein function. Here, we studied the proportion of sites evolving under structural constraints in two very different types of ensembles, those coming from ordered or disordered proteins. Using a structurally constrained model of protein evolution we found that both types of ensembles show comparable, near 40%, number of positions evolving under structural constraints. Among these sites, ~68% are in disordered regions and ~57% of them show long-range inter-residue contacts. Also, we found that disordered ensembles are redundant in reference to their structurally constrained evolutionary information and could be described on average with ~11 conformers. Despite the different complexity of the studied ensembles and proteins, the similar constraints reveal a comparable level of selective pressure to maintain their biological functions. These results highlight the importance of the evolutionary information to recover meaningful biological information to further characterize conformational ensembles.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Gulden Olgun ◽  
Afshan Nabi ◽  
Oznur Tastan

Abstract Background While some non-coding RNAs (ncRNAs) are assigned critical regulatory roles, most remain functionally uncharacterized. This presents a challenge whenever an interesting set of ncRNAs needs to be analyzed in a functional context. Transcripts located close-by on the genome are often regulated together. This genomic proximity on the sequence can hint at a functional association. Results We present a tool, NoRCE, that performs cis enrichment analysis for a given set of ncRNAs. Enrichment is carried out using the functional annotations of the coding genes located proximal to the input ncRNAs. Other biologically relevant information such as topologically associating domain (TAD) boundaries, co-expression patterns, and miRNA target prediction information can be incorporated to conduct a richer enrichment analysis. To this end, NoRCE includes several relevant datasets as part of its data repository, including cell-line specific TAD boundaries, functional gene sets, and expression data for coding & ncRNAs specific to cancer. Additionally, the users can utilize custom data files in their investigation. Enrichment results can be retrieved in a tabular format or visualized in several different ways. NoRCE is currently available for the following species: human, mouse, rat, zebrafish, fruit fly, worm, and yeast. Conclusions NoRCE is a platform-independent, user-friendly, comprehensive R package that can be used to gain insight into the functional importance of a list of ncRNAs of any type. The tool offers flexibility to conduct the users’ preferred set of analyses by designing their own pipeline of analysis. NoRCE is available in Bioconductor and https://github.com/guldenolgun/NoRCE.


Author(s):  
Anne Schienle ◽  
Albert Wabnegger

AbstractAn extremely bitter taste can signal food spoilage, and therefore typically elicits disgust. The present cross-modal functional magnetic resonance imaging experiment investigated whether the personality trait ‘disgust propensity’ (DP; temporally stable tendency to experience disgust across different situations) has an influence on the processing of visual food cues during bitter aftertaste perception. Thirty females with high DP and 30 females with low DP viewed images depicting sweet food (e.g., cakes, ice cream) and vegetables, once in combination with an extremely bitter aftertaste (concentrated wormwood tea), and once with a neutral taste (water). Females highly prone to disgust (compared to low disgust-prone females) showed increased activity in the anterior cingulate cortex (ACC) and increased mPFC-insula connectivity when presented with the mismatch of a bitter aftertaste and visual cues of sweet food. The ACC is involved in conflict monitoring and is strongly interconnected with insular areas. This connection plays a critical role in awareness of changes in homeostatic states. Our findings indicate that the personality trait DP is associated with cross-modal integration processes of disgust-relevant information. Females high in DP were more alert to food-related sensory mismatch (pleasant visual features, aversive taste) than females low in DP.


2021 ◽  
Author(s):  
Judith M. Varkevisser ◽  
Ralph Simon ◽  
Ezequiel Mendoza ◽  
Martin How ◽  
Idse van Hijlkema ◽  
...  

AbstractBird song and human speech are learned early in life and for both cases engagement with live social tutors generally leads to better learning outcomes than passive audio-only exposure. Real-world tutor–tutee relations are normally not uni- but multimodal and observations suggest that visual cues related to sound production might enhance vocal learning. We tested this hypothesis by pairing appropriate, colour-realistic, high frame-rate videos of a singing adult male zebra finch tutor with song playbacks and presenting these stimuli to juvenile zebra finches (Taeniopygia guttata). Juveniles exposed to song playbacks combined with video presentation of a singing bird approached the stimulus more often and spent more time close to it than juveniles exposed to audio playback only or audio playback combined with pixelated and time-reversed videos. However, higher engagement with the realistic audio–visual stimuli was not predictive of better song learning. Thus, although multimodality increased stimulus engagement and biologically relevant video content was more salient than colour and movement equivalent videos, the higher engagement with the realistic audio–visual stimuli did not lead to enhanced vocal learning. Whether the lack of three-dimensionality of a video tutor and/or the lack of meaningful social interaction make them less suitable for facilitating song learning than audio–visual exposure to a live tutor remains to be tested.


2016 ◽  
Vol 23 (9) ◽  
pp. 1240-1249 ◽  
Author(s):  
Sean R Locke ◽  
Lawrence R Brawley

Exercise-related cognitive errors reflect biased processing of exercise-relevant information. The purpose of this study was to examine whether differences existed between individuals reporting low and high exercise-related cognitive errors on information processed about a relevant exercise decision-making situation. In all, 138 adults completed an online questionnaire. The high exercise-related cognitive error group primarily focused on negative content about the situation compared to the low exercise-related cognitive error group who focused on both positive and negative content. The high exercise-related cognitive error group displayed biased processing of exercise information, as suggested by the cognitive errors model. Future research should examine whether biasing information processing caused by exercise-related cognitive errors can be modified and attenuated.


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