74 research outputs found
Meta-regression analysis of high-frequency ventilation vs conventional ventilation in infant respiratory distress syndrome
Jaw Laterality and Related Handedness in the Hunting Behavior of a Scale-Eating Characin, Exodon paradoxus
BACKGROUND: Asymmetry in animal bodies and behavior has evolved several times, but our knowledge of their linkage is limited. Tanganyikan scale-eating cichlids have well-known antisymmetry in their bodies and behavior; individuals open their mouths leftward (righty) or rightward (lefty), and righties always attack the right flank of the prey, whereas lefties attack the left. This study analyzed the morphological asymmetry in a scale-eating characiform, Exodon paradoxus, and its behavioral handedness. METHODOLOGY/PRINCIPAL FINDINGS: Each eight E. paradoxus was observed for 1-h with a prey goldfish in an aquarium to detect the behavioral handedness. Following the experiment, the lateral differences in the mandibles and head-inclination of these eight and ten additional specimens were analyzed. Both measurements on the morphology showed a bimodal distribution, and the laterality identified by these two methods was always consistent within a given individual, indicating that the characin has morphological antisymmetry. Furthermore, this laterality significantly corresponded to behavioral handedness; that is, lefties more often rasped scales from the right flank of the prey and vice versa. However, the correlation between laterality and handedness is the opposite of that in the cichlids. This is due to differences in the feeding apparatus and technique. The characin has cuspids pointing forward on the external side of the premaxilla, and it thrusts its dominant body side outward from its body axis on the flank of the prey to tear off scales. By contrast, the cichlids draw their dominant body side inward toward the axis or rotate it to scrape or wrench off scales with the teeth lined in the opened mouth. CONCLUSIONS/SIGNIFICANCE: This study demonstrated that the antisymmetry in external morphology and the corresponding behavioral handedness have evolved in two lineages of scale-eating fishes independently, and these fishes adopt different utilization of their body asymmetry to tear off scales
Ectoparasites as numerical dominant species in parasite community of Trachelyopterus striatulus (Siluriformes: Auchenipteridae) from Guandu River, southeastern Brazil
The influence of population structure and reproductive aspects of the genus Stellifer (Oken, 1817) on the abundance of species on the southern Brazilian coast
Regulation of miR‐125a expression by rs12976445 single‐nucleotide polymorphism is associated with radiotherapy‐induced pneumonitis in lung carcinoma patients
The Standard Genetic Code can Evolve from a Two-Letter GC Code Without Information Loss or Costly Reassignments
Length-weight Relationships and Condition Factor of Five Marine Finfish Species from Parangipettai (Tamil Nadu) and Mumbai (Maharashtra) Coast of India
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