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1. Body size (SL, mm) of females from supplemented (hatched) and non-supplemented (white) patch reefs at the beginning of the feeding experiment and after 45 days of food manipulation. Error bars represent SE.
Source publication
Selective mortality within a population, based on the phenotype of individuals, is the foundation of the theory of natural selection. Even small phenotypic differences among individuals early in ontogeny can strongly affect survival and performance later in life. Consequently, variation in early life history traits can have important repercussions...
Similar publications
Age-based studies of tropical reef fishes have been relatively slow moving. In some instances, good descriptions of age-specific demography have been obtained from the otoliths of fishes from low-latitude reef environments. For most reef species, validation has been achieved through chemical marking of calcareous structures or marginal increment an...
Citations
... These larger fish were better able to monopolize resources and became competitive dominants (possibly due to a covariance between growth and behavioural traits; Biro et al., 2004), which as a result predisposed an opportunity to change sex to males. Although higher otolith size at hatching has been associated with a larger larval size or higher metabolism at hatching (Vigliola & Meekan, 2002; Armstrong et al., 2004; Gagliano, 2007), and with higher larval and juvenile survival (Vigliola & Meekan, 2002), this is the first study to provide evidence that early larval growth may pro-rate individual fitness. Males had larger otoliths from the very first increment, suggesting that processes operating prior to spawning may have pre-determined which fish would later become the dominants in a harem. ...
The temporal relationship between growth history, sex-specific growth divergence and sex change was investigated in the haremic sandperch Parapercis snyderi using otolith microstructure and gonad histology. Parapercis synderi was found to display rapid near-linear growth with a maximum longevity of 303 days. All individuals matured first as female and later changed sex to become male (monandric protogynous hermaphroditism). Individual age-based growth histories obtained from otolith increment widths illustrated that males were larger than females at any given age. Males were found to diverge from the female growth trajectory during two ontogenetic periods; during the larval period and during the period that sex change took place. In addition, male otoliths contained a discontinuity, or ‘check mark’, associated with the rapid increase in otolith growth during the sex-change period. This microstructural feature was absent from all female otoliths. Accelerated growth in male otoliths lasted up to 25 days, following check-mark formation, after which time otolith growth returned to the pre-check-mark rate. Given the isometric relationship between otolith and somatic growth in P. synderi, and the temporal relationship between the time of check-mark formation and gonad condition, these results strongly suggest that individuals accelerate somatic growth during sex change to become the largest members of the population. Moreover, evidence suggests that the factors that determine the initial growth of larvae influence which individuals will later become males and achieve the highest reproductive success.
... These larger fish were better able to monopolize resources and became competitive dominants (possibly due to a covariance between growth and behavioural traits; Biro et al., 2004), which as a result predisposed an opportunity to change sex to males. Although higher otolith size at hatching has been associated with a larger larval size or higher metabolism at hatching (Vigliola & Meekan, 2002;Armstrong et al., 2004;Gagliano, 2007), and with higher larval and juvenile survival (Vigliola & Meekan, 2002), this is the first study to provide evidence that early larval growth may pro-rate individual fitness. ...
The temporal relationship between growth history, sex-specific growth divergence and sex
change was investigated in the haremic sandperch Parapercis snyderi using otolith microstructure
and gonad histology. Parapercis synderi was found to display rapid near-linear
growth with a maximum longevity of 303 days. All individuals matured first as female and
later changed sex to become male (monandric protogynous hermaphroditism). Individual agebased
growth histories obtained from otolith increment widths illustrated that males were
larger than females at any given age. Males were found to diverge from the female growth
trajectory during two ontogenetic periods; during the larval period and during the period that
sex change took place. In addition, male otoliths contained a discontinuity or ‘check mark’,
associated with the rapid increase in otolith growth during the sex-change period. This
microstructural feature was absent from all female otoliths. Accelerated growth in male
otoliths lasted up to 25 days, following check mark formation, after which time otolith growth
returned to the pre-check mark rate. Given the isometric relationship between otolith and
somatic growth in P. synderi, and the temporal relationship between the time of check mark
formation and gonad condition, these results strongly suggests that individuals accelerate
somatic growth during sex change to become the largest members of the population.
Moreover, evidence suggests that the factors that determine the initial growth of larvae
influence which individuals will later become males and achieve the highest reproductive
fitness.
