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Tad T. Brunyé Elena Andonova Chiara Meneghetti Matthijs L. Noordzij Francesca Pazzaglia Rasmus Wienemann Caroline R. Mahoney Holly A. Taylor 《Journal of environmental psychology》2012
Three studies test whether the southern route preference, which describes the tendency for route planners to disproportionately select south- rather than north-going routes, can be attributed to regional elevation patterns; specifically, we ask whether this effect replicates in three topographically disparate international regions, one of which is characterized by higher elevations to the north and lower to the south (Padua, Italy), and two characterized by higher elevations to the south and lower to the north (Enschede, Netherlands; Sofia, Bulgaria). In all cases, we found strong evidence that route planners disproportionately select south- rather than north-going routes at rates exceeding chance. We conclude that the southern route preference is driven by strong associations between canonical direction and perceived effort of route traversal; these effects are somewhat perplexing given that such associations are not founded in the reality of physical space. 相似文献
2.
The bipedal stance and gait of theropod dinosaurs evolved gradually along the lineage leading to birds and at some point(s), flight evolved. How and when did these changes occur? We review the evidence from neontology and palaeontology, including pectoral and pelvic limb functional morphology, fossil footprints/trackways and biomechanical models and simulations. We emphasise that many false dichotomies or categories have been applied to theropod form and function, and sometimes, these impede research progress. For example, dichotomisation of locomotor function into ‘non-avian’ and ‘avian’ modes is only a conceptual crutch; the evidence supports a continuous transition. Simplification of pelvic limb function into cursorial/non-cursorial morphologies or flexed/columnar poses has outlived its utility. For the pectoral limbs, even the classic predatory strike vs. flight wing-stroke distinction and separation of theropods into non-flying and flying—or terrestrial and arboreal—categories may be missing important subtleties. Distinguishing locomotor function between taxa, even with quantitative approaches, will always be fraught with ambiguity, making it difficult to find real differences if that ambiguity is properly acknowledged. There must be an ‘interpretive asymptote’ for reconstructing dinosaur limb function that available methods and evidence cannot overcome. We may be close to that limit, but how far can it be stretched with improved methods and evidence, if at all? The way forward is a combination of techniques that emphasises integration of neontological and palaeontological evidence and quantitative assessment of limb function cautiously applied with validated techniques and sensitivity analysis of unknown variables. 相似文献
3.
David J. Able 《Behavioral ecology and sociobiology》1999,46(6):423-428
Darwin predicted that scramble competition for access to reproductive females would result in sexual dimorphism of locomotory
structures, but direct evidence for this is extremely rare. I examined the relationship between variation in tailfin size
and mating success in a field and laboratory study of red-spotted newts, Notophthalmus viridescens. Over three breeding seasons, male tailfin size was positively correlated with variation in male amplexus frequency, and
indirectly correlated with male insemination frequency. In a laboratory study, I confirmed that males' ability to capture
females is affected by variation in tailfin size. This is the first study to show that naturally occurring variation in male
locomotory structures affects male mating success. It corroborates the prediction that scramble competition leads to sexual
selection on locomotory structures and, potentially, to dimorphism in these structures.
Received: 16 April 1999 / Received in revised form: 16 May 1999 / Accepted: 12 June 1999 相似文献
4.
Gastropod shells are limited resources for most hermit crab species, acting as primary factors in various aspects of their biology. To investigate the efficacy of different behavioral tactics adopted for their acquisition (locomotion, attendance at shell-supplying sites, interactions with conspecifics in aggregation) we conducted observations and experiments at a salt marsh in New England (USA). Locomotion, fast and meandering, significantly increased the chances of encountering empty shells and conspecifics. However, shell exchanges were rare. Simulated gastropod predation sites quickly attracted a larger number of hermit crabs than the other shell-supplying sites tested (live and dead conspecifics, live snails) and induced the rapid occupancy of all the empty shells offered, usually by the first crabs arriving at the site. Aggregations seemed not to function as shell exchange markets, as previously suggested for several other species. In the short run, exploitation seems to be more efficient for the acquisition of new shells by Pagurus longicarpus. In the long run, it is the density of nondestructive gastropod predators that regulates the availability of new shells of good quality in the pool available to this hermit crab species. 相似文献
5.
Anopheles gambiae s.l. is the main vector of malaria in Sub-Saharan Africa. Here, an estimated 1 million people die every year from this disease.
Despite considerable research on An. gambiae that increasingly explores sub-organismal phenomena, important facets of the field biology of this deadly insect are yet
being discovered. In the current study, we used simple observational tools to reveal that the habitat of larval An. gambiae is not limited within the boundaries of temporary mud puddles, as has been the accepted generalization. Thus, control tactics
aimed at immatures must consider zones larger than puddles per se. In fact, eggs are more likely to be found outside than
inside puddles. Eggs can develop and larvae can emerge on mud. Larvae are then capable of three distinct modes of terrestrial
displacement (two active and one passive), whereby, they can reach standing water. On mud bearing a film of water, larvae
actively displace backwards by sinusoidal undulations shown to be only a slight variation of the swimming motor program. On
drying mud, larvae switch to a slower and forward form of active locomotion resembling that of a crawling caterpillar. During
rains, small larvae may be passively displaced by flowing rainwater so as to be deposited into puddles. These capabilities
for being amphibious, along with very rapid growth and development, help explain how An. gambiae thrives in a highly uncertain and often hostile larval environment.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
6.
Hesselberg T 《Die Naturwissenschaften》2007,94(8):613-621
Biomimetics is a rapidly growing field both as an academic and as an applied discipline. This paper gives a short introduction
to the current status of the discipline before it describes three approaches to biomimetics: the mechanism-driven, which is
based on the study of a specific mechanism; the focused organism-driven, which is based on the study of one function in a
model organism; and the integrative organism-driven approach, where multiple functions of a model organism provide inspiration.
The first two are established approaches and include many modern studies and the famous biomimetic discoveries of Velcro and
the Lotus-Effect, whereas the last approach is not yet well recognized. The advantages of the integrative organism-driven
approach are discussed using the ragworms as a case study. A morphological and locomotory study of these marine polychaetes
reveals their biomimetic potential, which includes using their ability to move in slippery substrates as inspiration for novel
endoscopes, using their compound setae as models for passive friction structures and using their three gaits, slow crawling,
fast crawling, and swimming as well as their rapid burrowing technique to provide inspiration for the design of displacement
pumps and multifunctional robots. 相似文献
7.
Behavioral and faunal implications of Early Cretaceous deinonychosaur trackways from China 总被引:3,自引:1,他引:2
Li R Lockley MG Makovicky PJ Matsukawa M Norell MA Harris JD Liu M 《Die Naturwissenschaften》2008,95(3):185-191
Deinonychosaurian theropods, the dinosaurian sister group of birds, are characterized by a large raptorial claw borne on a highly modified second digit that was thought to be held in a retracted position during locomotion. In this study, we present new trackway evidence for two coeval deinonychosaurian taxa from the Early Cretaceous of Shandong, China that indicate a hitherto unrecognized body size diversity for this period and continent. These fossil tracks confirm diversity and locomotory patterns implied by phylogeny and biogeography, but not yet manifested in the body fossil record. Multiple parallel and closely spaced trackways generated by the larger track maker provide the best evidence yet discovered for gregarious behavior in deinonychosaurian theropods. 相似文献
8.
Daily perception entails an immediate awareness of the environment surrounding the body. To explore its dynamic nature during locomotion, this study tests the hypothesis that significant changes in spatial volume induce the directional focusing (i.e., anisotropy) of environmental perception. To capture perceptual activity in its natural state, we have attempted an approach using the feeling of visual pressure (i.e., felt presence) caused by the surrounding environment. In the present experiment that uses a virtual reality setup, participants were required to continuously rate their feelings while moving along a virtual outdoor route. Their ratings were analyzed in relation to environmental measurements along the route, such as the visible area of buildings and the horizontal extent of surrounding space. The relationship between the ratings and measurements was explored by using two prediction models: with and without consideration of perceptual anisotropy. The results suggested that a consideration of anisotropy improved the prediction accuracy, thereby supporting our hypothesis. 相似文献
9.
The aim of this study was to assess the effects of the widely used anti-depressant fluoxetine on behaviour (locomotion), moulting, neuromuscular transmission, energy production and anti-oxidant defences’ efficiency of the epibenthic crab Carcinus maenas. Crabs were individually exposed to fluoxetine concentrations for 7 d. Effects on locomotion were assessed at the end of the exposure using an open field test adapted to C. maenas in the present study. Tissue samples were later collected to evaluate fluoxetine effects on physiological functions using the activity of key enzymes and other parameters as biomarkers, namely: N-acetyl-β-glucosaminidase (NAGase) in the epidermis (moulting) and the hepatopancreas; cholinesterases (ChE) in muscle (neuromuscular cholinergic transmission); NADP+-dependent isocitrate dehydrogenase (IDH) and lactate dehydrogenease (LDH) in muscle (energy production); glutathione S-transferases (GST) in hepatopancreas (biotransformation and oxidative stress system); glutathione reductase (GR), and glutathione peroxidade (GPx), total glutathione levels (TG) and lipid peroxidation levels in the hepatopancreas (anti-oxidant defences and oxidative damage). Because no information on C. maenas NAGase activity was previously available, its variation during the moult cycle was also investigated. The results showed that locomotion was significantly increased at fluoxetine concentrations equal or above 120 μg L−1, with animals spending more time moving, walking longer distances than controls. Levels of NAGase activity were found to vary in relation to C. maenas moult cycle, but no alterations were observed after exposure to fluoxetine. Significant increases in the activity of ChE, GST and GR enzymes, and the levels of TG were found, with a lowest observed effect concentration (LOEC) of 120 μg L−1. Effects on locomotion were significantly and positively correlated to those induced on ChE activity. The results raise concern when hypothesising conditions of chronic exposure in the wild. 相似文献
10.
Joseph C. Spagna Adam Schelkopf Tiana Carrillo Andrew V. Suarez 《Die Naturwissenschaften》2009,96(2):243-250
Evolutionary co-option of existing structures for new functions is a powerful yet understudied mechanism for generating novelty.
Trap-jaw ants of the predatory genus Odontomachus are capable of some of the fastest self-propelled appendage movements ever recorded; their devastating strikes are not only
used to disable and capture prey, but produce enough force to launch the ants into the air. We tested four Odontomachus species in a variety of behavioral contexts to examine if their mandibles have been co-opted for an escape mechanism through
ballistic propulsion. We found that nest proximity makes no difference in interactions with prey, but that prey size has a
strong influence on the suite of behaviors employed by the ants. In trials involving a potential threat (another trap-jaw
ant species), vertical jumps were significantly more common in ants acting as intruders than in residents (i.e. a dangerous
context), while horizontal jumps occurred at the same rate in both contexts. Additionally, horizontal jump trajectories were
heavily influenced by the angle at which the substrate was struck and appear to be under little control by the ant. We conclude
that while horizontal jumps may be accidental side-effects of strikes against hard surfaces, vertical escape jumps are likely
intentional defensive behaviors that have been co-opted from the original prey-gathering and food-processing functions of
Odontomachus jaws. 相似文献
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