Supplementary methods – details on literature searches and data preparation
Literature search
Egg size data were predominantly obtained from a systematic search in Web of Science
(WoS) using the keyword combinations: marine fish and “egg size” (title) and “egg size”
(topic); reef fish and “egg size”, marine fish and “egg size” and “life history character*”;
marine fish and “egg size” and fecundity; fish and egg size, and papers citing Thresher
(1984). If the study included a reef fish family and had data on egg diameter, volume, or wet
weight it was retained. Reef fish families were determined by a list compiled from Thresher
(1984), Leis (1991), and Cowen and Sponaugle (1997). All species included were
crosschecked on FishBase (Froese and Pauly 2003) to ensure that species included were
associated with coral reef or rocky substrate. References were traced for articles with
compiled datasets, particularly Thresher (1984), Ware (1975), and Einum and Fleming
(2002). Post-hoc searches were done for specific families using the family name and egg size
as keywords. Additional egg size data were obtained from three larval guides (Okiyama
1988; Moser 1996; Richards 2006). When egg size searches were exhausted, clutch size data
were added post hoc for species with available egg size data. If the egg size paper did not
give clutch size, FishBase was searched using the search term “fecundity parameter”
followed by a search on WoS.
Data preparation
Due to the lack of consistency in whether error values were reported and the form in
which they were reported, intraspecies variation for egg and clutch size was not considered.
If a study listed a range of values – in the form of several individuals of the same species or
multiple measurements of the same species throughout a breeding season – the midpoint was
retained. If a study represented egg size graphically, the values were approximated using the
axis units and the mean value was calculated. Several families had species with ellipsoidal
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eggs (Apogonidae, Chaetondontidae, Gobiesocidae, Gobiidae, Labridae, Malacanthidae,
Ostraciidae, Pomacentridae, Scaridae, Synodontidae), given in papers as a length and width
and these dimensions were retained.
If clutch size was reported as a range or across seasons, the midpoint was retained.
For two demersal species (Parablennius ruber and Rhinecanthus aculeatus), the diameter of
a single egg mass was provided and we extrapolated the number of eggs based on clutch and
egg volume. Papers listing the population mean egg production or fecundity as a volume of
eggs were excluded from the database because no simple conversion among units was
possible. The majority of clutch sizes obtained for demersal spawners were collected
experimentally in the original studies to ensure that the clutch size was per female per
spawning and not an aggregate of multiple females laying eggs.
The maximum adult standard length for each species was obtained from FishBase. If
total length (i.e. the maximum length from the mouth and including the full caudal fin) values
were given, they were converted to standard lengths (mouth to caudal peduncle) using the
length-length parameters, which provide species-specific variables for the general equation
SL = b + aTL where total length is known and standard length unknown. Two species –
Apogon hungi and Archamia lineolata – did not have any length value listed in FishBase and
therefore the standard lengths were obtained from the original source (see ESM Table S6).
Several species in FishBase were listed with only total lengths without listing any lengthlength parameters. In these cases, the mean a and b values for the genus were calculated and
used as the approximate parameters. Standard length was chosen over mass for adult size
because there are more length data available and because length, not mass, is the common
variable in reproductive theory.
Phylogenetics
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To create a tree including the majority of our focal species, we used elements of
acanthomorph phylogenies (Li et al. 2009; Near et al. 2013) as backbones and augmented
with addition sequence data (as in Riginos et al. 2014). Specifically, we parsed rhodopsin
(Rhod) sequences (from Li et al. 2009) to retain focal fish families with species represented
in our data and to preserve selected fossil dated calibration points (from Santini et al. 2009,
nodes 24, 33, 34, 36, 37, 38, 42, and 44 from their Table 2). We added additional Rhod
sequences representing focal families as available from NCBI. NCBI and the Barcode of Life
Database (BOLD) were also queried for cytochrome oxidase I (COI) sequences for all focal
species and for each species with a Rhod sequence. Rhod and COI sequences were
concatenated with missing loci treated as missing data. A Bayesian search was conducted in
MrBayes (ver. 3.2, Ronquist and Huelsenbeck 2003), with four partitions representing the
two genes and treating third positions separately from first and second positions for each
gene. Taxonomic families and clades receiving ≥ 90% support on an acanthomorph supertree
(Near et al. 2013) were constrained to be monophyletic in our search. A search was
conducted using 10 million steps (sufficient for convergence in the two chains: s.d. < 0.01)
and a burnin of 2.5 million steps under a GTR + G + I model of evolution for each partition.
The resultant consensus tree was transformed to a chronogram using non-parametric rate
smoothing with penalized likelihood with the truncated Newton method (r8s ver. 1.7,
Sanderson 2002) using fossil calibration points (Sanderson 2009).
References
Cowen RK, Sponaugle S (1997) Early life history and recruitment in fish populations.
Chapman & Hall, New York.
Einum S, Fleming IA (2002 ) Does within-population variation in fish egg size reflect
maternal influences on optimal values? Am Nat 160:756–765
Froese R, Pauly D (2003) FishBase. www.fishbase.org
Leis JM (1991) The pelagic stage of reef fishes: the larval biology of coral reef fishes. In:
Sale PF (ed.) The ecology of fishes on coral reefs. Academic Press, San Diego, pp 183–
230
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Li B, Dettaï A, Cruaud C, Couloux A, Desoutter-Meniger M, Lecointre G (2009) RNF213, a
new nuclear marker for acanthomorph phylogeny. Mol Phylogenet Evol 50:345–363
Moser HG (ed.) (1996) The early stages of fishes in the California current region. California
cooperative oceanic fisheries investigations, CalCOFI Atlas No 33
Near TJ, Dornberg A, Eytan RI, Keck BP, Smith WL, Kuhn KL, Moore JA, Price SA,
Burbrink FT, Friedman M, Wainwright PC (2013) Phylogeny and tempo of diversification
in the superradiation of spiny-rayed fishes. Proc Natl Acad Sci U S A 110:12738–12743
Okiyama M (ed.) (1988) An atlas of the early stage fishes in Japan. Tokai University Press,
Tokyo
Richards WJ (ed.) (2006) Early stages of Atlantic fishes: an identification guide for the
Western Central North Atlantic, Vol 2. Taylor & Francis, United Kingdom
Riginos C, Buckley YM, Blomberg SP, Treml EA (2014) Dispersal capacity predicts both
population genetic structure and species richness in reef fishes. Am Nat 184:52–64
Ronquist F, Huelsenbeck JP (2003) MRBAYES 3: Bayesian phylogenetic inference under
mixed models. Bioinformatics 19:1572–1574
Sanderson MJ (2002) Estimating absolute rates of molecular evolution and divergence times:
a penalized likelihood approach. Mol Biol Evol 19:101–109
Santini F, Harmon LJ, Carnevale G, Alfaro ME (2009) Did genome duplication drive the
origin of teleosts? A comparative study of diversification in ray-finned fishes. BMC Evol
Biol 9:194
Thresher RE (1984) Reproduction in reef fishes. T.F.H. Neptune City, New York
Ware DM (1975) Relation between egg size, growth, and natural mortality of larval fish. J
Fish Res Board Can 32:2503–2512
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