spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online August 3, 2006
Journal of Experimental Biology 209, 3055-3061 (2006)
Published by The Company of Biologists 2006
doi: 10.1242/jeb.02336
This Article
Right arrow Summary Freely available
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Dzyuba, B.
Right arrow Articles by Holt, W. V.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Dzyuba, B.
Right arrow Articles by Holt, W. V.

Effect of parental age and associated size on fecundity, growth and survival in the yellow seahorse Hippocampus kuda

Borys Dzyuba1, Katrien J. W. Van Look2, Alex Cliffe3, Heather J. Koldewey3 and William V. Holt2,*

1 Institute for Problems of Cryobiology and Cryomedicine of the National Academy of Sciences of the Ukraine, 23 Pereyaslavskaya Street, Kharkov 310015, Ukraine
2 Institute of Zoology, Zoological Society of London, Regent's
3 Park, London NW1 4RY, UK and 3Zoological Society of London, Regent's Park, London NW1 4RY, UK


Figure 1
View larger version (12K):

[in a new window]
  		Fig. 1. Graph showing the relationship between height (mm) and body mass (g) for juvenile seahorses (N=89; r=0.98; P<0.0001).

 

Figure 2
View larger version (14K):

[in a new window]
  		Fig. 2. (A) Brood size comparison between old (OC) and young (YC) couples; box-whisker plot showing the mean ± s.e.m. (boxes) and s.d. (whiskers) (F1,10=6.45, *P=0.029). (B) Comparison of offspring survival curves from old (OC; open squares) and young (YC, solid circles) couples. Least-squares survival functions (fitted lines) for offspring from the OC (N=508, offspring from six couples) and YC (N=263, offspring from six couples). Survival of offspring from YC is significantly poorer than from OC (P<0.0001).

 

Figure 3
View larger version (11K):

[in a new window]
  		Fig. 3. Comparison of group mean (± s.e.m.) heights of offspring from the old couples (OC, open squares; N=6) and young couples (YC, solid circles; N=6) vs age (weeks). **P<0.001, F1,39=6.45.

 

Figure 4
View larger version (20K):

[in a new window]
  		Fig. 4. (A,B) Distribution histograms for heights of newborn seahorses from large parents (A) and small parents (B). Heights of newborns from the six large males showed a pronounced negative skew (coefficient of skew=-0.446; N=298; Shapiro-Wilks test; P=0.0018) but the newborns from small males did not show this skew (N=262). (C,D) Medians and 25th percentiles for the height distributions (mm) of newborn seahorse cohorts from large parents (C) and small parents (D) between weeks 1 and 7. Distributions with significant negative skews are indicated (*P<0.05 and **P<0.01).

 

Figure 5
View larger version (15K):

[in a new window]
  		Fig. 5. (A) Exemplar growth curves between weeks 1 and 7 for offspring from one old couple (OC; red open squares) and one young couple (YC; blue circles) male and their associated scatter of individual data points. (B,C) Scatterplots and linear regression lines for the relationships between cohort growth coefficients (q) and number of newborns in the cohorts, for large parents (OC; B) and small parents (YC; C). Significant and negative correlation and regressions were observed for the OC group (correlation: r=-0.82, P<0.05; regression: growth coefficient=30.456-0.1173xnumber of newborns; F1,4=7.94, P=0.047; N=6) but no corresponding correlation was observed for the YC group (r=0.048; P>0.9; N=6).

 

Figure 6
View larger version (100K):

[in a new window]
  		Fig. 6. (A) A photograph of a pregnant male seahorse with three transverse planes through the brood pouch indicated by lines 1-3. (B) MRI scans of transverse planes 1-3 (top to bottom). The positions of individual pouch embryos (PE) around the periphery of the brood pouch are indicated by arrows and the empty interior of the brood pouch is indicated by arrowheads. (C,D) Photographs of ventrally and dorsally located embryo attachment sites within the brood pouch (arrows). Ventrally located attachment sites are very shallow in comparison to those located dorsally. Scale bars, (A) 1.3 cm; (C,D) 3 mm.

 




© The Company of Biologists Ltd 2006