QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online January 27, 2004
Journal of Experimental Biology 207, 853-868 (2004)
Published by The Company of Biologists 2004
doi: 10.1242/jeb.00821

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Müller, U. K. Articles by van Leeuwen, J. L. Search for Related Content PubMed PubMed Citation Articles by Müller, U. K. Articles by van Leeuwen, J. L.

Swimming of larval zebrafish: ontogeny of body waves and implications for locomotory development

Ulrike K. Müller^* and Johan L. van Leeuwen

Wageningen University, Experimental Zoology Group, Marijkeweg 40, 6709 PG Wageningen, The Netherlands

View larger version (18K): [in a new window]   Fig. 1. Recordings of a swimming zebrafish larva for half a tail beat. (A) Cyclic swimming [age 3 days, mean swimming speed (U)=8 s–1]. (B) Slow start (age 2 days, U=0 s–1). (C) Fast turn (age 3 days). Scale bar, 1 mm.

View larger version (36K): [in a new window]   Fig. 2. Midline kinematics of zebrafish larvae (A–E; age 2, 3, 5 and 7 days post-fertilisation) during cyclic swimming. (i) Lateral view of the larva and midlines in a fish-based frame of reference. The superimposed midlines (time step 1 ms, scaled to the lateral view of the larva) of one tail beat cycle show the amplitude envelope of the body wave. The envelope has a minimum at 0.16–0.21 body length (L) located within the anterior third of the yolk sac (black oval: yolk sac; grey circle: otic placode at 0.16L). All larvae are scaled to be the same length. (ii) All midlines (black) of the recorded sequence (time step 1 ms) in an earth-based frame of reference. The path of the head and the tail are indicated in blue and red, respectively. The scale bar indicates 0.5L. The sequences were chosen for a similar swimming speed for the two categories `slow' and `fast' swimming.

View larger version (49K): [in a new window]   Fig. 3. Tail beat kinematics of zebrafish larvae (age 2, 3, 5 and 7 days post-fertilisation) during cyclic swimming and a slow start (age 2 days). Lateral position of tail tip (h; black), swimming speed (U; thin red line), lateral speed of tail tip (v; thick red line), angle of incidence (i; thick blue line) and angle of attack (a; thin blue line) of the tail over one tail beat cycle. All values are means based on two (age 7 days) or three tail beat cycles of one swimming sequence. The grey bars indicate roughly when swimming speed reaches a maximum during the tail beat cycle. U is expressed as % deviation from the specific swimming speed averaged over one complete tail beat (U): U=(U–U)/U.

View larger version (50K): [in a new window]   Fig. 4. Cyclic swimming in zebrafish larvae (3 days post-fertilisation; U=8 s–1) (A) Contours of the specific lateral displacement (negative values = displacements to the left of the larva) and (B) specific curvature (negative values = convex curvature), plotted along the body axis (x-axis) and in time (y-axis) for two complete tail beats. (C,D) Vertical and horizontal cross sections through the displacement (A) and the curvature contours (B), respectively. The contours correspond to Fig. 2B. The thick, black lines indicate zero lateral displacement (h0) and zero curvature (0) in A and B, respectively. The broken black lines indicate the changing position in time and space of local extremes in lateral displacement (hmax) and curvature (max), which correspond to the amplitude envelope of the displacement (transect A1; the asterisk indicates pivot point) and the curvature wave (transect B1). Horizontal cross sections (red lines) indicate the body wave (A,C, transect A1) and curvature wave (B,D, transect B1), respectively. The distance between the points at which the horizontal cross section crosses the h0 and 0 contours, respectively, is equivalent to half the wave length of the body wave and curvature wave, respectively. The vertical cyan lines (C,D, transects A2 and B2, respectively) indicate vertical cross sections. They indicate the propulsive wave in the displacement profile (transect A2) and the curvature wave in the curvature profile (transect B2).

View larger version (67K): [in a new window]   Fig. 5. Cyclic swimming in zebrafish larvae. Contours of the specific lateral displacement (left column) and specific curvature (right column) of the midlines of swimming larvae. Age post-fertilisation: A,E – 2 days; B,F – age 3 days; C,G – 5 days: D,H – 7 days. The contours are based on the same sequences as Fig. 2A,C,D,E. The thick, black lines indicate zero lateral displacement (h0; A–D) and zero curvature (0; E–H), respectively. Broken, black lines indicate the local extremes in the lateral displacement (hmax; A–D) and curvature (max; E–H). The horizontal cross sections (red lines) indicate instantaneous body waves (A–D) and curvature waves (E–H). For further explanation, see main text and Fig. 4.

View larger version (22K): [in a new window]   Fig. 6. Specific curvature along the first quadrant of the body wave in the posterior half of the body for zebrafish larvae (age 2–7 days post-fertilisation) during cyclic swimming (grey lines) and for juvenile eel (data re-analysed from Müller et al., 2000; red line) at the moment when the tail crosses the mean path of motion.

View larger version (20K): [in a new window]   Fig. 7. Plot of specific swimming speed (U) against tail beat frequency (f) for zebrafish larvae (age 2–7 days post-fertilisation) during cyclic swimming. The equation for the regression curve is f=–0.0076U2+1.65U–39.58; r2=0.92, total N=40.

View larger version (39K): [in a new window]   Fig. 8. Slow start of zebrafish larvae. Age post-fertilisation: (A) 2 days; (B) 4 days; (C) 7 days; (D) 14 days. (i) Amplitude envelope of the body wave. Larval midlines in a fish-based frame of reference for the 3rd tail beat cycle in the curvature profiles of the right column [time step 2 ms (A), 1 ms (B–D)]. Scale bar, 0.5L. In D, the 1st midline of the tail beat cycle is shown in red and the last midline in blue. (ii) Profiles of specific curvature. Contours of the specific curvature of the midlines, plotted along the body axis (x-axis) and in time (y-axis) for two complete tail beat cycles. The broken, black lines indicate the local curvature extremes.

View larger version (45K): [in a new window]   Fig. 9. Fast turn of zebrafish larvae. Age post-fertilisation: (A) 2 days; (B) 4 days; (C) 7 days; (D) 21 days. (i) Midlines of the larva in an earth frame of reference (time step 1 ms). Maximum translational speed: thin green midline; maximum acceleration: thick green midline. Scale bar, 0.5L. (ii) Profiles of specific curvature. Contours of the specific curvature of the midlines, plotted along the body axis (x-axis) and in time (y-axis) for one complete tail beat cycle.

View larger version (38K): [in a new window]   Fig. 10. Rate of curvature during cyclic swimming of zebrafish larvae. (A) Mean swimming speed over one complete tail beat (U)=8 s–1 (corresponds to Figs 2B, 4). (B) U=46 s–1 (corresponds to Figs 2C, 7B). The vertical profile for the higher swimming speed (B) exhibits wider plateaus with curvature rates near 0 and higher absolute extremes than that of slow swimming (A).