Zebrafish have a marvellous visual system for study. Their retinas have abundant cones of four spectral types, i.e. red-, green-, blue-and ultraviolet–sensitive cones. The animals are exceptionally responsive behaviourally; robust visual responses can be measured just four to five days after egg fertilization 1. My group has been carrying out forward genetic studies on zebrafish for about fifte...

The weakly electric glass knifefish, Eigenmannia virescens, will swim forward and backward, using propulsion from an anal ribbon fin, in response to motion of a computer-controlled moving refuge. Fish were recorded performing a refuge-tracking behavior for sinusoidal (predictable) and sum-of-sines (pseudo-random) refuge trajectories. For all trials, we observed high coherence between refuge and...

This paper presents a locomotion control implementation of a robotic system mimicking the undulating fins of fish. To mimic the actual flexible fin of a real fish, we created a ribbon fin type actuation device with a series of connecting linkages and attached it to the robotic fish. By virtue of a specially designed strip with a slider, each link is able to turn and slide with respect to the ad...

PURPOSE Photoreceptor ribbon synapses translate light-dependent changes of membrane potential into graded transmitter release over several orders of magnitude in intensity. A specialized organelle at the active zone--the synaptic ribbon--is a key player in this process, and it is well known that the ribbon undergoes illumination and thus activity-dependent structural changes. However, the molec...