scholarly journals Multimodal communication in courting fiddler crabs reveals male performance capacities

2017 ◽  
Vol 4 (3) ◽  
pp. 161093 ◽  
Author(s):  
Sophie L. Mowles ◽  
Michael Jennions ◽  
Patricia R. Y. Backwell
Keyword(s):  
Field Experiments ◽  
Fiddler Crabs ◽  
Vibrational Signal ◽  
Sprint Speed ◽  
Additional Signal ◽  
Additional Information ◽  
Waving Display ◽  
Redundant Signal ◽  
Strong Positive Relationship ◽  
Multimodal Signalling

Courting males often perform different behavioural displays that demonstrate aspects of their quality. Male fiddler crabs, Uca sp., are well known for their repetitive claw-waving display during courtship. However, in some species, males produce an additional signal by rapidly stridulating their claw, creating a ‘drumming’ vibrational signal through the substrate as a female approaches, and even continue to drum once inside their burrow. Here, we show that the switch from waving to drumming might provide additional information to the female about the quality of a male, and the properties of his burrow (multiple message hypothesis). Across males there was, however, a strong positive relationship between aspects of their waving and drumming displays, suggesting that drumming adheres to some predictions of the redundant signal hypothesis for multimodal signalling. In field experiments, we show that recent courtship is associated with a significant reduction in male sprint speed, which is commensurate with an oxygen debt. Even so, males that wave and drum more vigorously than their counterparts have a higher sprint speed. Drumming appears to be an energetically costly multimodal display of quality that females should attend to when making their mate choice decisions.

scholarly journals Rethinking a Designers’ Rule of Thumb: Influence of Information Seeking and Consumption Goals on Mobile Commerce Interface Design

2021 ◽  
Vol 16 (5) ◽  
pp. 1631-1647
Author(s):  
Sooa Hwang ◽  
Hyunah Park ◽  
Kyunghui Oh ◽  
Sangwoong Hwang ◽  
Jaewoo Joo
Keyword(s):  
Information Seeking ◽  
Interface Design ◽  
Field Experiments ◽  
Product Information ◽  
Mobile Commerce ◽  
Rule Of Thumb ◽  
Additional Information ◽  
Dynamic Relationship ◽  
The Usa ◽  
Consumption Goals

We investigated whether adding product information in mobile commerce improved consumers’ attitudes toward a product and whether this relationship was moderated by consumption goals. We conducted two field experiments in which we recruited parents in Korea and the USA and asked them how they evaluated two childcare hybrid products (HPs) newly developed by Samsung Electronics designers. The results revealed that participants exposed to additional information about the HPs evaluated them more favorably than those who were not exposed. However, this relationship disappeared when a consumption goal was activated. Our findings establish a dynamic relationship between information seeking and consumption goals, asking designers to rethink their rule of thumb in the mobile commerce context.

scholarly journals Improving Search Quality in Crowdsourced Bib Number Tagging Systems Using Data Fusion

Information ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 385
Author(s):  
Andrew Ponomarev
Keyword(s):  
Data Fusion ◽  
Graphical Models ◽  
Field Experiments ◽  
Fusion Model ◽  
Human Errors ◽  
Additional Information ◽  
Gps Tracks ◽  
Reasonable Choice ◽  
Using Data

Today, crowd computing is successfully applied for many information processing problems in a variety of domains. One of the most acute issues with crowd-powered systems is the quality of results (as humans can make errors). Therefore, a number of methods have been proposed to process the results obtained from the crowd in order to compensate human errors. Most of the existing methods of processing contributions are constructed based on a (natural) assumption that the only information available is unreliable data obtained from the crowd. However, in some cases, additional information is available, and it can be utilized in order to improve the overall quality of the result. The paper describes a crowd computing application for community tagging of running race photos. It presents a utility analysis to identify situations in which community photo tagging is a reasonable choice. It also proposes a data fusion model making use of runners’ location information recorded in their Global Positioning System (GPS) tracks. Field experiments with the applications show that community-based tagging can collect enough contributors to process photosets from medium-sized running events. Simulation results confirm, that the use of data fusion in processing the results of crowd computing is a promising technique, and the use of probabilistic graphical models (e.g., Bayesian networks) for data fusion allows one to smoothly increase the quality of the results with an increase of the available information.

Receiver female body size and distances affect the claw-waving rate of signaller males in fiddler crabs (Brachyura, Ocypodidae)

Behaviour ◽  
2018 ◽  
Vol 155 (10-12) ◽  
pp. 905-914 ◽  
Author(s):  
Fahmida W. Tina ◽  
M. Jaroensutasinee ◽  
K. Jaroensutasinee
Keyword(s):  
Body Size ◽  
Female Body ◽  
Carapace Width ◽  
Fiddler Crabs ◽  
Female Body Size ◽  
Waving Display ◽  
Body Sizes ◽  
Males And Females ◽  
First Time ◽  
Close Distance

Abstract We tested for the first time how Austruca bengali Crane, 1975 signaller males adjusted their waving rates based on receiver female body sizes and their distances. We video recorded the waving display of 46 males (9–12 mm carapace width) for 30 s, and counted their waving rate. Receiver females were categorised as small (8–10 mm carapace width) and large (>10 mm). Distances between males and females were categorised as short (⩽12 cm) and long (>12 cm) distances. Our results indicate that males are able to measure distances and female sizes, and adjust their waving display by actively reducing waving rate (1) towards small females, as usually small females have lower fecundity compared to large ones and (2) towards females at very close distance because at this point, the females would make their mating decision, and thus males start to lead/hit the females towards their burrow rather than waving vigorously.

Autotomy and running performance of fiddler crabs (Decapoda: Brachyura: Ocypodidae)

2019 ◽  
Vol 39 (5) ◽  
pp. 613-616
Author(s):  
Benjamin E Martin
Keyword(s):  
Recovery Time ◽  
Flat Surface ◽  
Fiddler Crab ◽  
Sexually Dimorphic ◽  
Fiddler Crabs ◽  
Running Performance ◽  
Sprint Speed ◽  
Negative Effect ◽  
Sprint Velocity ◽  
Locomotor Costs

Abstract The sexually dimorphic, enlarged major claw is a notorious trait among male fiddler crabs, but comes with potential locomotor costs. Possessing the ability to autotomize the enlarged claw is thus potentially advantageous to not only to escape a predator’s grip, but also to increase running performance. Previous studies concluded that autotomy either has no effect or even a negative effect on running performance. If the claw does not aid in locomotion, then shedding the enlarged claw that accounts for 40% of a fiddler crab’s mass should positively affect running performance. I therefore investigated autotomy and running performance in the Atlantic sand fiddler crab Leptuca pugilator (Bosc, 1801) with a focus on improving upon the methods of previous studies. Crabs were given substantial recovery time between collection, running trials, and autotomy induction. Maximum sprint speed was assessed by running crabs on a 1 m sand and mud track where individuals were significantly faster after autotomy of the enlarged claw (N = 64, t63=-7.25, P < 0.001). Intact running velocity was furthermore a significant predictor of autotomized running velocity (R2 = 0.194, P < 0.001). This study is the first to show a significant increase in fiddler crab sprint velocity after autotomy on a flat surface, and I propose where methodological pitfalls may have occurred in previous studies.

Visual vs Auditory Displays for Different Tasks of a Car Driver

1979 ◽  
Vol 23 (1) ◽  
pp. 35-39 ◽  
Author(s):  
D. Bouis ◽  
M. Voss ◽  
G. Geiser ◽  
R. Haller
Keyword(s):  
Field Experiments ◽  
Warning System ◽  
Auditory Signal ◽  
Visual Displays ◽  
Textual Information ◽  
Auditory Displays ◽  
Additional Information ◽  
Practical Design ◽  
Dynamic Signal

The development of new visual displays and speach synthesizers leads to the on board presentation of additional information to the car driver. A series of laboratory and field experiments was carried out to compare visual, auditory, and partly combined presentation of binary and textual information. From the results recommendations for practical design can be given. Binary alarms which occur seldomly and with high priority have to be a dynamic signal, e. g. a blinking lamp optionally supported by an intermittent auditory signal. For textual information a voice warning system is recommended.

Fiddler Crabs Use the Visual Horizon to Distinguish Predators from Conspecifics: A Review of the Evidence

1997 ◽  
Vol 77 (1) ◽  
pp. 43-54 ◽  
Author(s):  
John Layne ◽  
Michael Land ◽  
Jochen Zeil
Keyword(s):  
Field Experiments ◽  
Angular Size ◽  
White Background ◽  
Fiddler Crabs ◽  
Absolute Size ◽  
Uca Pugilator ◽  
Glass Dish ◽  
Escape Responses ◽  
The Absolute

Male fiddler crabs, Uca pugilator (Crustacea: Decapoda), respond to conspecifics by claw waving, and to predators by freezing or escape. In field experiments it was found that this distinction was not made on the basis of angular size and speed, nor was shape important. The remaining possibilities were either the absolute size of the stimulus, determined from angular size and distance, or the position of the stimulus relative to the horizon. To distinguish between these, a crab was placed in a glass dish, and moved black stimuli on a white background, at a distance of 22 cm. Stimuli below the crab's horizon hardly ever evoked escape. However, identical stimuli partially or wholly above the crab's horizon produced escape responses whose frequency varied with the angular size of the stimulus. Halving the distance of the stimulus showed that it was angular and not absolute size that determines escape frequency; and experiments with a tilted horizon showed that it is the position of the stimulus relative to the eye equator that is important, rather than the geographical horizon itself. It has been concluded that crabs categorize stimuli as dangerous or otherwise by their position relative to the crabs’ visual horizon.

INCREASE OF INFORMATION CONTENT WHEN TESTING THE METHOD OF RING LOADING

2018 ◽  
Vol 12 (7-8) ◽  
pp. 26-37 ◽  
Author(s):  
V. L. KUBETSKII ◽  
M. V. KOROLEV
Keyword(s):  
Large Scale ◽  
Field Experiments ◽  
Fractured Rock ◽  
Field Testing ◽  
Laboratory Equipment ◽  
Additional Information ◽  
Scale Field ◽  
Large Scale Field ◽  
Torque Load ◽  
Rock Pillars

In the construction of essential structures for the determination of the mechanical properties of large-scale heterogeneous fractured rock soils, people usually rely on the results of more representative large-scale field testing when assigning expected performances. Such large-scale field testing is conducted with the help of concrete stamps or rock pillars, usually with a square in plan outsole, for compression and flat shear, in galleries or in open sites. However, there are drawbacks: the complexity in the implementation and interpretation of the testing data, low informativeness, etc. Due to the rectangular shape of the stamp, a very uneven stress state is implemented at its base during shear. In order to eliminate these drawbacks in 1979 V.L. Kubetskiy offered the method of the ring loading, in which the square base of a stamp (a pillar) was replaced by a ringone, and the shift was carried out by applying a torque load to the stamp. This gives the possibility to realize various stress-strain state in the soil massif, to provide a more uniform contact stress diagram at its base, to obtain technological advantages and additional information during the experiment and to interpret the experimental data more reasonably and reliably using more modern models. Adescription of the method, loading schemes, developed field and laboratory equipment, results and interpretation of field experiments using isotropic and transversally isotropic soil models is given. The ways of method modernization using inventory installations are described. Taking into consideration that the common trend of improving the methods of geomechanical testings is aimed to increase the accuracy and informativity and at the same time to decrease the labor intensity, the method of ring loading which is being improving nowadays is still competitive.

Internode elongation pattern and differential response of rice genotypes to varying levels of flood water

2012 ◽  
Vol 39 (2) ◽  
pp. 137 ◽  
Author(s):  
Annamalai Anandan ◽  
Govindrajan Rajiv ◽  
Akkisetty Ramarao ◽  
Muthu Prakash
Keyword(s):  
Leaf Area ◽  
Field Experiments ◽  
Carbon Fixation ◽  
Shoot Elongation ◽  
Internode Elongation ◽  
Rice Plants ◽  
Escape Strategy ◽  
Strong Positive Relationship ◽  
Rice Genotypes ◽  
Primary Stem

Rice plants are damaged during floods by complete or partial submergence. The pattern of expression of rice plant varies with different flood regimes. Accordingly, the morphological and physiological responses of rice genotypes were studied in field and pot experiments under different flood regimes. Wide genetic base lines of Oryza sativa and sub 1 introgressed submergence tolerant were compared in field experiments using principle component analysis. Further, based on internode elongation pattern, two genotypes – Bodikaburi and Pokkali – were selected for a pot experiment to find more on elongation pattern of internodes under different flood regimes. Short-term submergence in minimal water, elongation of blade, sheath, leaf area, DW, number of nodes in primary stem and survival present showed strong positive relationship with shoot length. Number of tillers, leaf area and DW were more affected and decreased during submergence than its non-submergence counterpart. Under different flooding regimes, cvv Bodikaburi and Pokkali exhibited different behaviour in the elongation pattern of the shoot. Partial submergence accelerated elongation of all internodes whereas complete submergence accelerated the top internode. Enhancement of shoot elongation during submergence in water is an escape strategy adopted by rice to resume aerobic metabolism and to improve carbon fixation. This escape strategy varies among genotypes with respect to different flooding regimes. Therefore, breeders should be aware of breeding of rice plants with suitable architecture for different flood- prone environments.

Visual and Acoustic Display in Uca Mordax and U. Burgersi, Sibling Species of Neotropical Fiddler Crabs. Ii. Vibration Signals

Behaviour ◽  
1984 ◽  
Vol 91 (1-3) ◽  
pp. 204-227 ◽  
Author(s):  
Heinrich-Otto VON HAGEN
Keyword(s):  
Sibling Species ◽  
Character Displacement ◽  
Fiddler Crabs ◽  
Vibration Signals ◽  
Allopatric Populations ◽  
Interspecific Differences ◽  
Waving Display ◽  
Starting Point ◽  
The Common ◽  
Species Specific

AbstractThe sibling species of fiddler crabs, Uca mordax and U. burgersi, which are very similar in respect to morphology and many traits of their waving display (see part I of this study), were studied bioacoustically in Trinidad (W.I.). When recording their vibration signals (mainly in the laboratory) it was, at the same time, possible to directly observe the animals' underground activities. The dominant vibration signals of the two species were found to be extremely different: males of U. mordax emit rapping sounds ("drumwhirls") by ambulatory percussion, whereas males of U. burgersi produce "howling" sounds (with a varying number of harmonics) by cheliped convulsion, i.e. inconspicuous quivering movements of this appendage. Similar interspecific differences exist in the fainter vibration signals of females. Each of the two species is capable of producing other signals in addition to the prevalent ones mentioned: U. mordax can emit cheliped vibrations as well (though percussive ones) and U. burgersi can also produce ambulatory "drumwhirls". From these and other basic similarities and from comparisons with recordings of burgersi sounds from Colombia and allopatric populations in Florida, the common starting-point and the different evolutionary pathways leading to the two species-specific termini of acoustic display are reconstructed. The extreme differences that were found for the sympatric situation in Trinidad are regarded as an example of character displacement. Apparently, the acoustic communication system of these crabs is much more affected by character displacement than the visual one.

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