Teleosts have an asymmetrical caudal fin skeleton formed by the upward bending of the caudal-most portion of the body axis, the ural region. This homocercal type of caudal fin ensures powerful and complex locomotion and is regarded as one of the most important innovations for teleosts during adaptive radiation in an aquatic environment. However, the mechanisms that create asymmetric caudal fin ...

a series of two experiments was conducted to study the optimum dietary protein level and protein to energy ratio of lemon fin barb hybrid larvae. in experiment 1, five isocaloric diets (4700 kcal per kg) ranging from 40 to 60% protein in 5% increments were fed to triplicate groups of lemon fin barb hybrid larvae (initial weight: 0.10 ± 0.01 mg per fish) for 21 days. weight gain of fish was prop...

A triangular fin with variable fin base thickness is analyzed and optimized using a two-dimensional analytical method. The influence of fin base height and fin base thickness on the temperature in the fin is listed. For the fixed fin volumes, the maximum heat loss, the corresponding optimum fin effectiveness, fin base height and fin tip length as a function of the fin base thickness, convection...

in this paper, two-dimensional heat transfer in a semi-infinite wall with fins of rectangular profile has been investigated. the conduction equations of the wall and fins are solved simultaneously by a numerical method. the principal parameters of the problem are the fin spacing, length, and fin-to-wall conductivity ratio. in this investigation, the effect of these parameters on two-dimensional...

Body patterning behavior in unshelled cephalopod molluscs such as squid, octopuses, and cuttlefish is the ability of these animals to create complex patterns on their skin. This behavior is generated primarily by chromatophores, pigment-containing organs that are directly innervated by central motoneurons. The present study focuses on innervation patterns and location of chromatophore motoneuro...

We designed a robotic fish caudal fin with six individually moveable fin rays based on the tail of the bluegill sunfish, Lepomis macrochirus. Previous fish robotic tail designs have loosely resembled the caudal fin of fishes, but have not incorporated key biomechanical components such as fin rays that can be controlled to generate complex tail conformations and motion programs similar to those ...

Ray-finned fishes are notable for having flexible fins that allow for the control of fluid forces. A number of studies have addressed the muscular control, kinematics, and hydrodynamics of flexible fins, but little work has investigated just how flexible ray-finned fish fin rays are, and how flexibility affects their response to environmental perturbations. Analysis of pectoral fin rays of blue...

Zebrafish fins grow by sequentially adding new segments of bone to the distal end of each fin ray. In wild type zebrafish, segment addition is regulated such that an isometric relationship is maintained between fin length and body length over the lifespan of the growing fish. Using a novel, surrogate marker for fin growth in conjunction with cell proliferation assays, we demonstrate here that s...

The role of the pectoral fin bud for outgrowth by fin axons was assessed by ablation of pectoral fin buds and by transplantation of fin buds to ectopic sites in the embryos of the Japanese medaka fish (Oryzias latipes). Normally nerves from segments 1-4 (S1-4) and less frequently the S5 nerve converged at the base of the fin bud by extending toward the fin bud on the ventral surface of the axia...

in this paper, wavelet collocation method has been used to solve nonlinear fin problem with temperature dependent thermal conductivity and heat transfer coefficient. thermal conductivity of fin materials varies any type so that we consider thermal conductivity as the general function of temperature.  here we consider three particular cases, where we assume that thermal conductivity is constant,...