Interspecific patterns for egg and clutch sizes of African Bufonidae (Amphibia: Anura)

Accepted Manuscript Title: Interspecific patterns for egg and clutch sizes of African Bufonidae (Amphibia: Anura) Author: H. Christoph Liedtke Hendrik M¨uller Julian Hafner Peter Nagel Simon P. Loader PII: DOI: Reference:

S0044-5231(14)00006-0 http://dx.doi.org/doi:10.1016/j.jcz.2014.02.003 JCZ 25278

To appear in: Received date: Revised date: Accepted date:

15-11-2013 13-2-2014 23-2-2014

Please cite this article as: H. Christoph LiedtkeHendrik M¨ullerJulian HafnerPeter NagelSimon P. Loader Interspecific patterns for egg and clutch sizes of African Bufonidae (Amphibia: Anura) (2014), http://dx.doi.org/10.1016/j.jcz.2014.02.003 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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Interspecific patterns for egg and clutch sizes of African Bufonidae (Amphibia: Anura)

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H. Christoph Liedtke1*, Hendrik Müller 2, Julian Hafner1, Peter Nagel1, Simon P. Loader1

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Klingelbergstrasse 27, 4056 Basel, Switzerland

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Department of Environmental Science (Biogeography), University of Basel,

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Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-

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Schiller-Universität Jena, Erbertstraße 1, 07743 Jena, Germany *

Corresponding author: [email protected]

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10  Abstract

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Little is known about reproductive trade-offs in African amphibians, but such data,

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particularly in the form of quantitative measurements, are a key for investigating life history

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evolution. Here we compile and analyse known data on African bufonids from published

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material and new data from preserved museum specimens, to investigate interspecific patterns

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of egg and clutch sizes variation. Our data is a composite of mixed sources, including ova

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data from dissected females and laid clutches from observations in the field. Our study shows

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that, as body size increases, clutch size increases but egg size decreases, and when correcting

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for body size, egg size is inversely correlated with clutch size. These parameter interactions

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however, are different for different reproductive modes. In free-swimming larval developing

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species, the same trends are recovered, but for lecithotrophic viviparous species no significant

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correlations could be recovered for clutch size and body size nor for the trade-off between

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clutch size and egg size, and egg size is positively related to body size. The egg size of

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Nimbaphrynoides occidentalis (Angel, 1943) is a clear outlier, which may be due to its

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matrotrophic viviparous reproduction. In addition, we observed no statistical difference

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between ova data collected from dissections and laid clutch data from field observations,

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which suggests that such a mixed dataset has utility in comparative analyses.

28  Key words

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Ova; field observations; life history; trade-off; reproductive mode; lecithotrophic viviparity;

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matrotrophic viviparity

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32  1. Introduction

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Life history theory predicts that key ontogenetic processes such as the timing and allocation

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of reproductive efforts are strongly subjected to natural selection in favour of maximizing an

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individual’s inclusive fitness. The study of life history theory is therefore largely concerned

37 

with understanding why such an immense variation in reproductive strategies exists in nature

38 

and whether an optimization hypothesis can always be recovered as the underlying

39 

explanation (Stearns, 2000). The trade-off between the number of offspring and parental

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investment per offspring for example has been the focus of many fundamental concepts in

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ecology and evolution (e.g. Lack, 1947; MacArthur and Wilson, 1967; Van Noordwijk and de

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Jong, 1986) and the size and number of eggs per clutch is known to vary strongly both within

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(Cummins, 1986; Williamson and Bull, 1995; Christians, 2002; Berven, 2008) and between

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(Kuramoto, 1978; Blackburn, 1991; Figuerola and Green, 2005; Martin et al., 2006) species.

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For amphibians relationships between egg diameter and the number of eggs per clutch

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are central measures used to characterize reproductive modes, along with oviposition site, rate

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and duration of development, size of hatchling and type of parental care (Salthe and

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Duellman, 1973). Already in 1886, Boulenger noted that terrestrially breeding amphibians

49 

generally have larger eggs, but lay fewer than their aquatic breeding counterparts (Boulenger,

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1886). Since then, numerous other studies have investigated the interspecific relationship of

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egg and clutch size (e.g. Wake, 1978; Barbault, 1984; Hödl, 1990; Pupin et al., 2010);

 

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reviewed in (Duellman and Trueb, 1994; Wells, 2007), but African taxa tend to be

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underrepresented in broad scale comparative analyses (e.g. Summers et al., 2006; Wells,

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2007; Gomez-Mestre et al., 2012), or are only the subject of studies that focus on a single

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taxon (Barbault, 1984; phrynobatrachus Rödel and Ernst, 2002; Boulengerula Malonza and

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Measey, 2005). Here, we investigate interspecific patterns in clutch and egg size in relation to

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body size of true toads of Africa (Family Bufonidae) to test whether a trade-off exists

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between the two. Bufonids are interesting for this kind of study given the starkly contrasting

59 

breeding strategies they exhibit (e.g. Van Bocxlaer et al., 2010) and African bufonids

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specifically cover a particularly broad range of life history strategies, from large bodied,

61 

temporary pond breeders such as Amietophrynus gutturalis (Power, 1927) depositing tens of

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thousands of eggs (Channing and Howell, 2006) to the small, habitat specialist, matrotrophic

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viviparous toad Nimbaphrynoides occidentalis with extremely reduced clutches of no more

64 

than 17 eggs (Angel and Lamotte, 1944). Wells (2007) has shown that egg and clutch size

65 

relationships vary between different reproductive modes, but restricted his sampling to New

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World amphibian lineages. To test whether the same is true for African bufonids, we compare

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trends in life history parameters in species with free-swimming larva and species that give

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birth to live young in the form of lecithotrophic viviparity (formerly referred to as

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ovoviviparity Blackburn, 1999) and matrotrophic viviparity.

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Researchers working on Afro-tropical systems are often faced with problems of data

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availability and compatibility. Even when data are available, observations stem from varying

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types of quantitative and qualitative measures and composites of this nature are often needed

73 

to compile a suitable number of data points for meaningful analyses. We therefore also

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investigated whether egg counts and measurements taken from dissections of preserved,

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gravid females are comparable to data collected from field observations of laid clutches by

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testing whether trends observed for “ovarian clutches” are significantly different than those

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for “laid clutches”.

 

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78  2. Methods

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2.1 Data collection

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An exhaustive literature search for data on egg diameter and the number of eggs per clutch for

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African bufonid species was carried out. Information was compiled from primary literature

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indexed and searchable via Google Scholar (Google Inc., CA, USA) and

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webofknowledge.com (Thomson Reuters, Zurich, Switzerland) and from library searches for

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un-indexed journals, books and field guides in personal literature collections and the library

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of the University of Basel as well as the Natural History Museum (NHM), London. In cases

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where the literature source did not explicitly state or otherwise infer how counts or

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measurements were obtained, data was assumed to refer to laid clutches, not dissections.

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The literature dataset was complemented with new data collected for this study. The collections of the NHM and the Museum für Naturkunde, Berlin were visited and gravid

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females with visibly distended abdomens were dissected to retrieve the ovarian egg mass.

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Investigators were careful not to cause excessive damage to specimen, by either using pre-

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existing incisions (likely made by collectors to allow for preservatives to enter the body

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cavity) or by making incisions on only one side of the specimen, by cutting a crescent shape

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from just below the armpit along the flank towards the inguinal region. Eggs were gently

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lifted out of the body cavity with forceps and placed onto a glass plate and kept moist with

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70% methylated spirit.

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Information on the clutch and egg size for Barbarophryne brongersmai (Hoogmoed,

1972) was also generated de novo for this study, but refers to a laid clutch from a breeding program, not from a dissected female.

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Clutch sizes below 300 eggs were counted exactly and clutches larger than this were

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divided into smaller, equal sized portions, one of which was counted and this number was

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then multiplied by the number of egg portions to get an estimate total clutch size. Egg

 

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diameter was measured to the nearest 0.1 mm using dial callipers. Where possible, multiple

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individuals of each species were dissected to obtain repeated measures per species.

106  2.2 Statistical analyses

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The ideal dataset for this kind of study would consist of egg, clutch and body size

109 

measurements of the same female. However, this information is rarely published and so

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maximum records per species were used, which produces the most extensive dataset. Snout-

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vent length, the measurement from the tip of the snout to the cloaca, was used as a body size

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measurement, egg diameter without a gelatinous layer was used as an egg size measurement

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and counts of the number of eggs in one clutch determined clutch size. All measures were

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natural log transformed, and correlations of egg and clutch size with body size were explored

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with linear regressions. Separate regression slopes were calculated for species with different

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reproductive modes and clutch types (ovarian and laid clutches). Reproductive mode

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categories were defined as development as free-swimming tadpoles (including Altiphryniodes

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malcolmi [Grandison, 1978], which is arguably not strictly free-swimming, but see

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discussion), lecithotrophic viviparity and matrotrophic viviparity (as defined by Wourms,

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1981), however the last was excluded from statistical analyses as due to a sample size of one

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(Nimbaphrynoides occidentalis). All coding is listed in Table 1. To test whether the

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regression slopes were significantly different for each of the groupings, Analyses of

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Covariances (ANCOVAs) with type III sum of squares were carried out using the Anova

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function in the car package (Fox and Weisberg, 2011) in R v.3.0.0 (R core team, 2013). In

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cases where the assumptions for parametric testing were not met, significance was tested

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using a permutation test implementing the aovp function in the R package lmPerm (Wheeler,

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2010). The residuals for egg and clutch size on body size of a reduced dataset with species

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containing missing data removed were then used to plot egg size residuals against clutch size

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residuals. Although the variables at hand show linear relationships (after natural log

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transformations), using residuals to partial out the effect of a third variable is still considered

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bad practice (Garcia-Berthou, 2001) and this was therefore only done to graphically explore

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the relationship between these two traits. To statistically test whether a significant correlation

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exists and whether this is affected by either of the reproductive modes or the clutch types,

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ANCOVAs with female body size as a covariate were carried out. For all tests, non-

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significant interaction terms were removed and if the reduced model was not a significantly

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worse fit (tested using the anova function in the basic stat package in R), this model was

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preferred.

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138  3. Results

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Egg and clutch size data was collected from dissections of 35 females covering 19 species

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(Table 1S). The total dataset comprises 60 species (of just over 100 described species of

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African bufonids; AmphibiaWeb, 2013), clutch size data for 56, and egg size data for 54 of

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these species are included, with 50 species having information for both (Table 1; literature

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sources in Table S2).

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3.1 Clutch size

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The frequency distribution of clutch sizes is heavily skewed with the majority of African

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bufonid species laying less than 2000 eggs per clutch (mean=3597; Figure 1A). For the

149 

complete data set, clutch size is strongly, positively related to female body size ( =3.552,

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adjusted R2= 0.818, p<0.001). When taking account of the different clutch types and

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reproductive modes, individual regression slopes continue to show a positive relationship of

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ovarian and laid clutch size with body size (Figure 1B and C), however this relationship is not

153 

statistically supported for lecithotrophic viviparous species (adjusted R2=0.306, p=0.071).

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The ANCOVA on clutch size and body size with clutch type as a treatment effect shows that there is no significant interaction between body size and clutch type suggesting

 

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that the two clutch type slopes are similar and the interaction term can be removed from the

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model. The reduced model is not a significantly worse fit (F=0.181, p=0.672) and is therefore

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preferred over one including the interaction term. In this model, body size shows a strong,

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positive effect on clutch size (F=198.736, p<0.001; Table 2a), with no significant treatment

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effect of clutch type (F=0.460, p=0.501; Table 2a).

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The homogeneity of variance assumption of an ANCOVA when using reproductive

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mode as a treatment effect was not met (Levene’s test; F=18.817, p<0.001) and therefore a

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permutation test was used instead (Table 2b). The interaction term for body size and

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reproductive mode was not significant and was therefore removed. The reduced model is not

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a significantly worse fit (F=0.2447, p=0.124) and is therefore preferred over one including

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the interaction term. For the reduced model, both female body size and reproductive mode

167 

were recovered as having a significant effect on clutch size (F=179.674, p<0.001 and

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F=5.676, p<0.05 respectively; Table 2b), which indicates that although clutch size varies

169 

with body size, there is also a difference in pattern between lecithotrophic viviparous and

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free-swimming larva species. The regression slopes depicted in Figure 1C suggest that for

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both reproductive modes, a positive relationship of clutch size and female body size can be

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observed, with the effect being strong in free-swimming larva species, but not statistically

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different from zero for lecithotrophic viviparous species.

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3.2 Egg size

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Egg size shows a slight log normal distribution with a mean diameter of 1.936 mm (Figure

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2A). Without sub setting the data, egg size is inversely correlated to female body size ( =-

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0.209, adjusted R2= 0.140, p<0.05). Nimbaphrynoides occidentalis, the only matrotrophic

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viviparous anuran, is a clear outlier, with an egg size well below what is expected for its body

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size (represented by a hollow point in Figure 2C).

 

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The inverse relationship is maintained when sub-setting the data into ovarian and laid clutches, although the slope for ovarian data is not statistically different from zero (adjusted

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R2= 0.058, p=0.135; Figure 2B). If N. occidentalis is treated as an outlier and removed, a

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significant negative relationship is recovered ( =-0.234, adjusted R2= 0.280, p=0.005; slope

185 

not shown). For reproductive mode as a treatment effect, the regression slope for species with

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larval development indicates a negative relationship for egg size and body size (adjusted R2=

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0.298, p<0.001; Figure 2C), but for lecithotrophic viviparous species, this relationship is

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positive (adjusted R2= 0.634, p<0.05; Figure 2C).

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When comparing the two clutch types, the interaction term for the ANCOVA of egg size and body size is not significant, suggesting that the two slopes are similar and as for

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clutch size, the reduced model is not a significantly worse fit (F=0.507, p=0.480). Body size

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has a significant effect on clutch size (F=12.027, p<0.05; Table 3a), with no significant

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treatment effect of clutch type (F=2.347, p=0.132, Table 3a).

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When looking at reproductive mode as the grouping variable, the interaction term was significant (F=5.399, p<0.05; Table 3b), meaning the slopes of the two regression lines

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(Figure 2C) are significantly different from one another. Body size is inversely correlated

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with egg size in larval developing species but the reverse is true for lecithotrophic viviparous

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species.

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3.3 Egg vs. Clutch Size

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Clutch size and egg size regressions on body size are more or less linear (see Figure 1 and 2)

202 

and therefore the residuals of each regression could be used as a means of removing the effect

203 

of body size. When doing so, there is a negative overall relationship between the residuals of

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egg size and clutch size ( =-0.079, adjusted R2=0.064, p=0.045). This relationship is

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intensified when Nimbaphrynoides occidentalis is removed ( =-0.127, adjusted R2=0.308,

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p<0.001). For both laid and ovarian clutches, the negative relationship is maintained (Figure

 

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3A), but only if N. occidentalis is removed, is the slope for the ovarian clutch dataset

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significantly different from zero ( =-0.166, adjusted R2=0.459, p<0.001; regression line not

209 

shown). For the regression slopes representing the different reproductive modes, both larval

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developing and lecithotrophic viviparous species show a negative relationship (Figure 3B)

211 

although the relationship for the latter is not statistically different from zero ( =-0.180,

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adjusted R2=0.230, p=0.189).

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When comparing the two clutch types (not including N. occidentalis), none of the interaction terms for the ANCOVA are significant suggesting the slopes are similar and the

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reduced model is not a significantly worse fit (F=0.940, p=0.451). In the reduced model,

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clutch size has the strongest effect on egg size (F=21.303, p<0.001; Table 4a) with female

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body size and clutch type having no significant effect (F=2.148, p=0.150 and F=3.864,

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p=0.056 respectively; Table 4a).

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When comparing the two reproductive modes, again, none of the interaction terms for

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the ANCOVA are significant and similarly, the reduced model is not a significantly worse fit

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(F=1.219, p=0.318). In the reduced model, reproductive mode has no significant effect on the

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model (F=2.057, p=0.159; Table 4b) and the main driver is clutch size (F=22.454, p<0.001;

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Table 4b) with female body size not contributing significantly (F=3.537, p=0.067; Table 4b).

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4. Discussion

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In African bufonids, both egg number per clutch and egg size are correlated with body size.

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As body size increases, clutch size increases, but egg size decreases, and when correcting for

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body size, a strong negative correlation is evident for egg size on clutch size. Whether data

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originated from laid clutches or from dissected females had no effect on any general patterns

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and thus, we propose that data from both sources could be combined for broad-scale

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comparative studies in the future. However, reproductive mode had a significant effect on

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how egg size and clutch size are correlated with body size (though not on how these two

 

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parameters are correlated with each other after correcting for body size), in line with what

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Wells (2007) observed for Neotropical species. Our dissections of Mertensophryne micranotis

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(Loveridge, 1925) and M. uzunguensis (Loveridge, 1932) also provide new record number of

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eggs for these species, with egg counts for both exceeding any previous records by a factor of

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two or more (Grandison and Ashe, 1983; Poynton et al., 2005).

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Larval developing species retain a significant, positive correlation of clutch size with body size as well as inverse correlations of egg size with body size, and of egg size with

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clutch size (after correcting for body size). For lecithotrophic viviparous species, the slopes of

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the regression lines for clutch size on body size and for body size corrected egg size on clutch

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size showed the same trends as for larval developing species, however they were not

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significantly different from zero, suggesting weak correlations. The regression slope for egg

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size on body size was significantly different from zero and supported a positive correlation of

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egg size with body size, the reverse for what was recovered for larval developing species.

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The positive relationship between clutch size and body size is one that has been

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recovered in previous studies on amphibians (Kuramoto, 1978; Barbault, 1984; Duellman and

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Trueb, 1994; Prado and Haddad, 2005; Wells, 2007) and the most straight forward

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explanation for this is that larger bodied females can carry larger numbers of eggs (Roff,

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2002). This however assumes that egg size is relatively constant and one cannot rule out that

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both body size and fecundity respond to external factors in a collinear fashion and thus there

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may not be a direct causal link between the two. For example, Lüddecke (2002) found that

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within a single species, body size increased with altitude as did clutch size, even after the

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effect of increasing body size was removed.

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Salthe and Duellmann (1973) note that New World anurans practicing the same

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reproductive mode show a positive interspecific correlation between egg size and female

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body size, but when investigating this relationship across multiple reproductive modes, the

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correlation is inverted. Egg size and body size of African Bufonids appears to behave

 

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similarly, showing an overall inverse correlation, but as the dataset is subdivided into distinct

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reproductive modes, lecithortophic viviparous species show a positive correlation. Larval

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developing species continue to show a negative correlation, which may be an indication that

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this categories is too heterogeneous, pooling explosive pond breeders such as Amietophrynus

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gutturalis with terrestrial nest breeders such as Altiphrynoides malcolmi. Finer categorization

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of reproductive modes of African bufonids is hampered by the lack of detailed knowledge of

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the life history of many taxa and highly specialized reproductive modes such as the breeding

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in tree cavities and provisioning of post-hatching parental care as practiced by Nectophryne

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spp Bucholz and Peters, 1875 are usually represented by too low numbers of species to obtain

268 

sufficient sample sizes for statistical testing. A statistically viable refinement of the free-

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swimming larval developing category would be to firstly remove species with highly

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specialized modes such as those involving terrestrial nest building (e.g. Altiphrynoides

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malcolmi) or internal fertilization (e.g. Mertensophryne micranotis) and then separating

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species with larva developing in permanent water bodies from those with larva developing in

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temporary water bodies. The recovered regression slopes for these two groups continue to

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show negative correlations of egg size and body size ( = -0.178 and -0.315 respectively), but

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both slopes are no longer significantly different from zero (p=0.063 and 0.057 respectively).

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The viviparous Nimbaphrynoides occidentalis produces considerably smaller eggs

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than is expected for its body size and Angel and Lamotte (1944) comment that the eggs are

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hugely deprived of yolk. The toad is the only known matrotrophic viviparous anuran and

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embryos undergo complete development in the uterus of the mother over a period of nine

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months (Gallien, 1959; Castanet et al., 2000). A similar egg size reduction associated with

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matrotrophic viviparity has been observed for reptiles (Blackburn et al., 1984) and mammals

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(Dunbrack and Ramsay, 1989), as developmental energy is no longer provided by yolk stores

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in the egg, but directly from the mother.

 

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After correcting for body size, bufonids of both reproductive modes (free-swimming larva versus live-bearing) exhibit an inverse correlation between egg size and clutch size,

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corresponding to previous findings (Duellman and Trueb, 1994; Wells, 2007; Vitt and

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Caldwell, 2009) as well as the general principle of MacArthur and Wilson’s theory of r-

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versus K selection in populations (MacArthur and Wilson, 1967; Pianka, 1970). This theory

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predicts that if there are no density effects or competition, the optimum strategy for an

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organism would be to maximize fecundity, with minimal investment into each individual (r-

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selection). If an environment is saturated, the optimum shifts to the other extreme, wherein it

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is more beneficial for an organism to reduce the number of offspring produced, but to

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increase the investment per offspring (K-selection). Dobzhansky (1950) reasoned that K-

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selection should be favoured in climatically stable environments such as the tropics, whereas

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in temperate or high altitude regions, r-selection strategies would be more successful. The

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clear trade-off seen in African bufonids may therefore reflect the environments to which

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individual species are adapted and therefore offers an interesting system for investigating the

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relationship of life history parameters and habitat.

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The collection of life history data in the field is often difficult. Direct observations of

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species are often frustrated by the geographical location of species and/or the frequency and

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rarity of some species. In addition, species with more derived life-histories often breed in

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cryptic or difficult to observe locations, making it challenging to obtain quantitative and

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qualitative life history data. This is particularly true for Africa where basic data on the

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ecology and breeding biology of many species are still lacking. In our study, we compared the

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utility of data obtained from field observations and museum specimens and proved that there

306 

is no significant difference between both data sources, meaning that both sets of data can be

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combined in more comprehensive analyses. Preserved material from natural history

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collections is therefore an important resource for significantly adding to our knowledge on

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amphibian life history.

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310  Acknowledgements

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We would like to thank Mark Wilkinson, David Gower, Barry Clarke, Patrick Campbell,

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Frank Tillack and Mark-Oliver Rödel for granting us access to museum collections and for

314 

providing useful references and literature. Thank you also to Sergé Bogaerts for kindly

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providing a preserved clutch of B. brongersmai eggs and to Ruth Streitwolf for her help with

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researching the literature. This research was supported by the Swiss National Science

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Foundation (31003A-133067 granted to S.P.L).

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311 

318  References

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419 

 

17

Page 17 of 32

419  Appendix

421 

Table 1S. Egg diameter (in mm), clutch size and body size (snout vent length in mm) of

422 

dissected female toads housed in museum collections. In cases where egg size data is missing,

423 

ova were unusually small and likely to not be matured and therefore not measured, and where

424 

clutch size is missing, the females have been previously dissected and not the full clutch was

425 

preserved. BMNH numbers refer to vouchers housed in the Natural History Museum, London

426 

and ZMB numbers are housed at the Museum für Naturkunde, Berlin.

Voucher Number

Clutch Size ~9000

Snout Vent Length 91.5

Eggs pigmented? pigmented

1.7

~4000

75.3

pigmented

~2000

78.1

pigmented

~2100

66

pigmented

62

pigmented

BMNH1974.428

Amietophrynus brauni

BMNH1974.430

Amietophrynus camerunensis

BMNH1975.181

Amietophrynus camerunensis

BMNH1982.130

1.7

Amietophrynus camerunensis

BMNH1984.239

1.6

Amietophrynus kisoloensis

BMNH1934.12.15.272

1.9

~1800

74.2

pigmented

Amietophrynus kisoloensis

BMNH1934.12.15.274

1.6

~2100

78.4

pigmented

Amietophrynus kisoloensis

BMNH1957.1.13.51

d

~2400

75.1

pigmented

1.5

~2500

58.5

pigmented

BMNH1932.9.9.2

1.4

~2400

65.6

pigmented

BMNH1932.9.9.6

1.2

~1600

55.8

pigmented

Ac ce p

Amietophrynus lemairii

1.7

BMNH1932.9.9.2

te

Amietophrynus lemairii

M

Amietophrynus brauni

Amietophrynus lemairii

 

Egg Diameter (in mm) 1.0

an

Species

us

cr

ip t

420 

Amietophrynus pardalis

BMNH11.4.21.10.11

1.5

~14000

132.8

pigmented

Amietophrynus tuberosus

BMNH1969.508

1.1

~4200

59

pigmented

Amietophrynus tuberosus

BMNH58.11.2.154

1.5

~2700

68.5

pigmented

Amietophrynus urunguensis

BMNH1985.1006

0.6

~60

25.2

unpigmented

Amietophrynus xeros

BMNH1952.1.7.39

1.0

~5000

73.4

pigmented

Amietophrynus xeros

BMNH1984.172

~2400

68.1

pigmented

Didynamipus sjostedti

BMNH1969.1637

2.4

18

20.2

unpigmented

Duttaphrynus dodsoni

BMNH1931.7.20.55

1.5

410

63.3

pigmented

Duttaphrynus dodsoni

BMNH1931.7.20.60

1.3

470

57.2

pigmented

Duttaphrynus stuarti

BMNH1940.6.2.26

2.8

~2200

92.5

pigmented

Mertensophryne lindneri

BMNH1978.611

2.1

81

25

unpigmented

Mertensophryne lindneri

BMNH2000.729

2.1

57

24.6

unpigmented

Mertensophryne loveridgei

BMNH1988.246

1.9

82

32.8

unpigmented

Mertensophryne loveridgei

BMNH1988.7

2.1

131

32.4

unpigmented

Mertensophryne micranotis

BMNH1980.198

1.7

70

Mertensophryne micranotis

BMNH1982.85

1.8

Mertensophryne uzunguensis

BMNH2002.157

0.8

188

33.2

unpigmented

Nectophryne batesii

BMNH1978.805

2.1

23

23.6

unpigmented

18

unpigmented unpigmented

Page 18 of 32

Nectophrynoides vestergaardi

BMNH1982.499

Nectophrynoides viviparus

BMNH2005.822

Nectophrynoides viviparus

46 2.9

unpigmented

160

49.4

unpigmented

BMNH2005.827

2.6

96

37.6

unpigmented

Werneria bambutensis

ZMB76850

1.6

380

385

unpigmented

Werneria bambutensis

ZMB76698

1.9

344

420

unpigmented

Ac ce p

te

d

M

an

us

cr

ip t

427 

 

19

Page 19 of 32

427  428 

Table 2S. References from which female body sizes, clutch size and egg size information

429 

listed in Table 1 was obtained.  Max. Female Body Size ( Snout Vent Length in mm)

Maximum Recorded Clutch Size

Maximum Recorded Egg Size (Diameter in mm)

Altiphrynoides malcolmi

(Largen and Sprawls, 2010)

(Grandison, 1978)

(Wake, 1980)

Altiphrynoides osgoodi

(Largen and Sprawls, 2010)

(Wake, 1980)

(Grandison, 1978)

Amietophrynus brauni

(Channing and Howell, 2006)

this study

this study

(Frétey et al., 2011)

Amietophrynus channingi

(Barej et al., 2011)

Amietophrynus garmani

(Channing and Howell, 2006) (Channing and Howell, 2006)

Amietophrynus gracilipes

Amietophrynus lemairii Amietophrynus maculatus

M

cr

(Channing and Howell, 2006)

(Perret, 1966) (Channing and Howell, 2006) (Perret, 1966) (Channing and Howell, 2006)

this study

this study

(Channing, 2001)

this study

this study

(Channing and Howell, 2006)

(Rödel, 1996)

(Rödel, 1996)

(Schleich et al., 1996)

(Schleich et al., 1996)

(Schleich et al., 1996)

Amietophrynus pantherinus

(Preez et al., 2009)

(Channing, 2001)

Amietophrynus pardalis

(Channing, 2001)

this study

Amietophrynus poweri

(Channing, 2001)

(Channing, 2001)

Amietophrynus rangeri

(Channing, 2001)

(Minter et al., 2004)

(Channing, 2001)

(Largen and Sprawls, 2010)

(Schleich et al., 1996)

(Barbault, 1984)

Amietophrynus superciliaris

(Barej et al., 2011)

(Barej et al., 2011)

(Barej et al., 2011)

Amietophrynus tuberosus

(Frétey et al., 2011)

this study

this study

(Channing and Howell, 2006)

this study

this study

(Hoogmoed, 1972)

this study

this study

(Rödel, 1996)

(Rödel, 1996)

(Rödel, 1996)

(Channing, 2001)

(Grandison, 1980)

(Grandison, 1980)

Amietophrynus regularis

Amietophrynus xeros Barbarophryne brongersmai Bufo pentoni Capensibufo rosei

 

(Barej et al., 2011)

(Channing and Howell, 2006)

Ac ce p

Amietophrynus mauritanicus

(Barej et al., 2011)

d

Amietophrynus kisoloensis

this study

(Channing and Howell, 2006) (Channing and Howell, 2006)

te

Amietophrynus gutturalis

(Perret, 1966)

this study

an

Amietophrynus funereus

us

Amietophrynus camerunensis

ip t

Species

20

this study

Page 20 of 32

(Preez et al., 2009)

(Channing, 2001)

(Channing, 2001)

Didynamipus sjostedti

(Grandison, 1981)

(Grandison, 1981)

(Grandison, 1981)

Duttaphrynus dodsoni

(Largen and Sprawls, 2010)

this study

this study

Laurentophryne parkeri

(Laurent, 1950)

(Tihen, 1960)

(Grandison, 1981)

Mertensophryne anotis

(Channing, 2001)

(Channing, 2001)

(Channing, 2001)

(Channing and Howell, 2006) (Channing and Howell, 2006) (Poynton and Broadley, 1988) (Channing and Howell, 2006) (Poynton and Broadley, 1988) (Channing and Howell, 2006) (Channing and Howell, 2006) (Channing and Howell, 2006) (Channing and Howell, 2006)

(Poynton and Clarke, 1999)

Mertensophryne melanopleura Mertensophryne micranotis Mertensophryne taitana Mertensophryne usambarae Mertensophryne uzunguensis

(Channing and Howell, 2006) this study

this study

(Tihen, 1960)

(Tihen, 1960)

this study

this study

(Ngwava et al., 2009)

(Ngwava et al., 2009)

(Poynton and Clarke, 1999)

(Poynton and Clarke, 1999)

this study

(Poynton et al., 2005)

(Perret, 1966)

(Perret, 1966)

(Perret, 1966)

Nectophryne batesii

(Perret, 1966)

(Perret, 1966)

(Perret, 1966)

(Channing and Howell, 2006) (Channing and Howell, 2006)

(Channing and Howell, 2006) (Channing and Howell, 2006) (Channing et al., 2005) (Channing and Howell, 2006) (Menegon et al., 2007) (Menegon et al., 2004)

(Harper et al., 2010)

Ac ce p

Nectophrynoides laticeps

te

Nectophrynoides cryptus

d

Nectophryne afra

Nectophrynoides asperginis

Nectophrynoides minutus

(Channing and Howell, 2006)

Nectophrynoides paulae

(Harper et al., 2010)

(Poynton et al., 1998) (Perret, 1972) (Channing et al., 2005) (Perret, 1972)

(Channing and Howell, 2006) (Channing and Howell, 2006) (Channing and Howell, 2006) (Channing and Howell, 2006) (Sandberger et al., 2010) and Sandberger pers. comm.

this study

this study

(Angel and Lamotte, 1944)

(Gallien, 1959)

Poyntonophrynus dombensis

(Channing, 2001)

(Channing, 2001)

(Channing, 2001)

Poyntonophrynus fenoulheti

(Channing, 2001)

(Lambiris, 1989)

(Lambiris, 1989)

Schismaderma carens

(Channing, 2001)

(Channing, 2001)

(Channing, 2001)

Vandijkophrynus amatolicus

(Channing, 2001)

Nectophrynoides poyntoni Nectophrynoides tornieri

Nectophrynoides vestergaardi Nectophrynoides viviparus

Nimbaphrynoides occidentalis

 

this study

cr

Mertensophryne loveridgei

(Poynton and Clarke, 1999)

us

Mertensophryne lonnbergi

this study

an

Mertensophryne lindneri

M

Mertensophryne howelli

ip t

Capensibufo tradouwi

21

(Gallien, 1959)

(Gallien, 1959)

this study

(Channing, 2001)

Page 21 of 32

Vandijkophrynus angusticeps

(Channing, 2001)

Vandijkophrynus gariepensis

(Channing, 2001)

Vandijkophrynus robinsoni

(Channing, 2001)

(Minter et al., 2004)

Werneria bambutensis

(Rödel et al., 2004)

(Amiet, 1976)

(Amiet, 1976)

Werneria tandyi

(Rödel et al., 2004)

(Amiet, 1976)

(Amiet, 1976)

(Channing, 2001)

(Channing, 2001)

Wolterstroffina parvipalmata

(Mertens, 1939)

(Mertens, 1939)

cr

430 

ip t

(Channing, 2001)

References for Table 2S

432 

Amiet, J.L., 1976. Observations anatomiques et biologiques sur le genre Werneria Poche,

433 

an

Angel, F., Lamotte, M., 1944. Un crapaud vivipare d'Afrique occidentale Nectophyrnoides

435  436 

occidentalis Angel. Annales des Sciences naturelles, Zoologie 6, 63–86.

M

434 

1903. Revue de Zoologie africaine 90, 33–45.

us

431 

Barbault, R., 1984. Stratégies de reproduction et démographie de quelques amphibiens

437 

anoures tropicaux. Oikos 43, 77–87.

Barej, M.F., Schmitz, A., Menegon, M., Hillers, A., Hinkel, H., Böhme, W., Rödel, M., 2011.

439 

Dusted off—the African Amietophrynus superciliaris-species complex of giant toads.

440 

Zootaxa 2772, 1–32.

Channing, A., 2001. Amphibians of Central and Southern Africa. Comstock

442  443 

te

Ac ce p

441 

d

438 

Publishing/Cornell University Press, Ithaca, New York.

Channing, A., Howell, K.M., 2006. Amphibians of East Africa. Comstock Pub. Associates,

444 

Cornell University Press, Ithaca, NY.

445 

Channing, A., Menegon, M., Salvidio, S., Akker, S., 2005. A new forest toad from the

446 

Ukaguru Mountains, Tanzania (Bufonidae: Nectophrynoides): original article.

447 

Frétey, T., Dewynter, M., Blanc, C.P., 2011. Amphibiens d“Afrique centrale et d”Angola,

448  449 

Collection Parthénope. Biotope Éditions. Gallien, L., 1959. Endocrine basis for reproductive adaptations in Amphibia, in: Gorbman, A.

450 

(Ed.), Comparative Endocrinology. Wiley, New York, pp. 479–487.

 

22

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451 

Grandison, A.G.C., 1978. The occurrence of Nectophrynoides (Anura Bufonidae) in Ethiopia.

452 

A new concept of the genus with a description of a new species. Monitore zoologico

453 

italiano. Supplemento XI 119–172. Grandison, A.G.C., 1980. Aspects of breeding morphology in Mertensophryne micranotis

ip t

454 

(Anura: Bufonidae): secondary sexual characters, eggs and tadpole. Bulletin of the British

456 

Museum of Natural History (Zoology) 39, 299–304.

457 

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455 

Grandison, A.G.C., 1981. Morphology and phylogenetic position of the west african Didynamipus sjoestedti Andersoon, 1903 (Anura Bufonidae). Monitore zoologico

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italiano. Supplemento XV 187–215.

Harper, E.B., Measey, G.J., Patrick, D.A., Menegon, M., Vonesh, J.R., 2010. Field Guide to

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460 

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458 

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462 

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464  465 

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Lambiris, A.J.L., 1989. The Frogs of Zimbabwe. Museo Regionale di Scienze Naturali

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Hoogmoed, M.S., 1972. On a new species of toad from southern Morocco. Zoologische

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472 

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475 

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476 

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485 

the Taita dwarf toad Mertensophryne taitana on Mt. Mbololo, Taita Hills, Kenya. African

486 

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Perret, J.L., 1966. Les amphibiens du Cameroun. Zool Jb Syst 8, 289–464.

488 

Perret, J.L., 1972. Les espèces des genres Wolterstoffina et Nectophrynoides d'Afrique

M

487 

489 

(Amphibia Bufonidae). Annales de la Faculté des Sciences du Cameroun 11, 93–119. Poynton, J.C., Broadley, D.G., 1988. Amphibia Zambesiaca 4. Bufonidae 1–44.

491 

Poynton, J.C., Clarke, B.T., 1999. Two new species of Stephopaedes (Anura: Bufonidae)

492 

from Tanzania, with a review of the genus. African Journal of Herpetology 48, 1–14.

te

Ac ce p

493 

d

490 

Poynton, J.C., Howell, K.M., Clarke, B.T., Lovett, J.C., 1998. A critically endangered new

494 

species of Nectophrynoides (Anura: Bufonidae) from the Kihansi Gorge, Udzungwa

495  496 

mountains, Tanzania. African Journal of Herpetology 47, 59–67.

Poynton, J.C., Menegon, M., Salvidio, S., 2005. Bufo uzunguensis of southern Tanzania

497  498 

(Amphibia: Anura): a history of confusion. African Journal of Herpetology 54, 159–170.

Preez, Du, L.H., Carruthers, V., Burger, M., 2009. A complete guide to the frogs of Southern

499  500 

Africa. Struik Nature, Cape Town, South Africa. Rödel, M.-O., 1996. Amphibien der Westafrikanischen Savanne, Edition Chimaira. Edition

501  502 

Chimaira, Frankfurt am Main. Rödel, M.-O., Schmitz, A., Pauwels, O.S.G., Böhme, W., 2004. Revision of the genus

 

24

Page 24 of 32

503 

Werneria Poche, 1903, including the descriptions of two new species from Cameroon and

504 

Gabon (Amphibia: Anura: Bufonidae). Zootaxa 720, 1–28.

505 

Sandberger, L., Hillers, A., Doumbia, J., Loua, N.S., Brede, C., Rödel, M., 2010. Rediscovery of the Liberian Nimba toad, Nimbaphrynoides liberiensis (Xavier, 1978)(Amphibia:

507 

Anura: Bufonidae), and reassessment of its taxonomic status. Zootaxa 2355, 56–68.

508 

Schleich, H.H., Kästle, W., Kabisch, K., 1996. Die Amphibien und Reptilien Nordafrikas. S.

509 

Koeltz, Königstein.

Tihen, J., 1960. Two new genera of African bufonids, with remarks on the phylogeny of

511 

us

510 

cr

ip t

506 

related genera. Copeia 1960, 225–233.

Wake, M.H., 1980. The reproductive biology of Nectophrynoides malcolmi (Amphibia:

513 

Bufonidae), with comments on the evolution of reproductive modes in the genus

514 

Nectophrynoides. Copeia 2, 193–209.

M

an

512 

Ac ce p

te

d

515 

 

25

Page 25 of 32

515  Figure captions

517 

Fig. 1. Clutch sizes of African bufonids. (A) Frequency histogram of clutch sizes per species

518 

with a magnification of clutch sizes below 2000. (B) Clutch size in relation to female body

519 

size with different regression slopes for laid clutches (black; =3.583, adjusted R2=0.757,

520 

p<0.001) compared to ovarian clutches (grey; =3.371, adjusted R2=0.817, p<0.001). (C)

521 

Regression slopes for lecithotrophic viviparous species (black; =1.607, adjusted R2=0.306,

522 

p=0.071) compared to larval developing species (grey; =3.331, adjusted R2=0.794,

523 

p<0.001). The hollow point represents the matrotrophic viviparous Nimbaphrynoides

524 

occidentalis.

an

us

cr

ip t

516 

525 

Fig. 2. Egg sizes of African bufonids. (A) Frequency histogram of egg size of African

527 

bufonids. (B) Egg size in relation to female body size with different regression slopes for laid

528 

clutches (black; =-0.288, adjusted R2=0.274, p=0.002) compared to ovarian clutches (grey;

529 

=-0.133, adjusted R =0.058, p=0.134). (C) Regression slopes for lecithotrophic viviparous

530 

species (black; =0.398, adjusted R2=0.634, p=0.036) compared to larval developing species

531 

(grey; =-0.270, adjusted R2=0.298, p<0.001). The hollow point represents the matrotrophic

532 

viviparous Nimbaphrynoides occidentalis.

Ac ce p

te

2

d

M

526 

533  534 

Fig. 3. Residuals for clutch size and egg size on body size, showing different regression

535 

slopes for (A) laid clutches (black; =-0.109, adjusted R2=0.224, p=0.009) and ovarian

536 

clutches (grey; =-0.024, adjusted R2=-0.043, p=0.757) and for (B) lecithotrophic viviparous

537 

species (black; =-0.180, adjusted R2=0.230, p=0.189) and larval developing species (grey;

538  539 

=-0.134 adjusted R2= 0.327, p<0.001). The hollow point represents the matrotrophic viviparous Nimbaphrynoides occidentalis.

540 

 

26

Page 26 of 32

Altiphrynoides malcolmi (Grandison, 1978)

Max. Egg Size (in mm)

31

3.9

62

307

Amietophrynus brauni (Nieden, 1911)

110

9000

Amietophrynus camerunensis (Parker, 1936)

91

2100

143

Amietophrynus gracilipes (Boulenger, 1899) Amietophrynus gutturalis (Power, 1927) Amietophrynus kisoloensis (Loveridge, 1932)

Amietophrynus maculatus (Hallowell, 1854) Amietophrynus mauritanicus (Schlegel, 1841)

d

Amietophrynus pantherinus (Smith, 1828) Amietophrynus pardalis (Hewitt, 1935)

Amietophrynus rangeri (Hewitt, 1935) Amietophrynus regularis (Reuss, 1833)

te

Amietophrynus poweri (Hewitt, 1935)

laid

FST

laid

FST

1

ovarian

FST

1.7

ovarian

FST

2

laid

FST

66

unknown

1.4

ovarian

FST

20000

1.2

laid

FST

41

unknown

1.5

laid

FST

120

23000

1.45

laid

FST

87

2400

1.9

ovarian

FST

70

2500

1.5

ovarian

FST

M

Amietophrynus lemairii (Boulenger, 1901)

Reproductive Mode

115

an

Amietophrynus garmani (Meek, 1897)

4500

Clutch Type

3

us

Altiphrynoides osgoodi (Loveridge, 1932)

Amietophrynus channingi Barej, Schmitz, Menegon, Hillers, Hinkel, Böhme and Rödl, 2011 Amietophrynus funereus (Bocage, 1866)

80

8000

1.5

laid

FST

150

10000

1.5

laid

FST

140

24476

unknown

laid

FST

147

14000

1.5

ovarian

FST

100

23000

unknown

laid

FST

115

10760

1.3

laid

FST

1.3

laid

FST

130

11000

Amietophrynus superciliaris (Boulenger, 1888)

163

4000

2

laid

FST

Amietophrynus tuberosus (Günther, 1858)

74

4200

1.5

ovarian

FST

92.7

5000

1

laid

FST

Amietophrynus xeros (Tandy, Tandy, Keith, and Duff-MacKay, 1976) Barbarophryne brongersmai (Hoogmoed, 1972)

 

Max. Clutch Size

cr

Max. Female Body Size (in mm) 31

Species

ip t

Table 1. Maximum female body size (measured as snout vent length in mm), clutch size and egg size (diameter in mm) for all species included in this study and coding for the two treatment classes “clutch type” (whether data originated from field observations of laid clutches [laid], or dissected gravid females from museum collections [ovarian]) and “reproductive mode” (whether species undergo larval development as free-swimming tadpoles [FST] or give birth to live young in the form of either lecithotrophic [LV] or matrotrophic viviparity [MV]).

Ac ce p

540  541  542  543  544  545  546 

51

690

1.7

laid

FST

"Bufo" pentoni Anderson, 1893

95

2600

2

laid

FST

Capensibufo rosei (Hewitt, 1926)

39

90

2.5

laid

FST

Capensibufo tradouwi (Hewitt, 1926)

48

60

2

laid

FST

Didynamipus sjostedti Andersson, 1903

2.3

ovarian

FST

19

18

Duttaphrynus dodsoni (Boulenger, 1895)

64

470

1.5

ovarian

FST

Laurentophryne parkeri (Laurent, 1950)

27.1

30

2.0

ovarian

unknown

Mertensophryne anotis (Boulenger, 1907)

46

105

2.5

laid

FST

Mertensophryne howelli (Poynton and Clarke, 1999)

45

60

2.5

ovarian

FST

Mertensophryne lindneri (Mertens, 1955)

34

81

2.1

ovarian

FST

Mertensophryne lonnbergi (Andersson, 1911)

44

125

2.5

laid

FST

Mertensophryne loveridgei (Poynton, 1991)

38

131

2.1

ovarian

FST

Mertensophryne melanopleura (Schmidt and Inger, 1959)

27

35

2

laid

FST

Mertensophryne micranotis (Loveridge, 1925)

24

70

1.8

ovarian

FST

Mertensophryne taitana (Peters, 1878)

33

350

2

laid

FST

27

Page 27 of 32

45

60

2.4

ovarian

FST

Mertensophryne uzunguensis (Loveridge, 1932)

30

188

2

ovarian

FST

Nectophryne afra Buchholz and Peters, 1875

25

40

2.5

ovarian

FST

Nectophryne batesii Boulenger, 1913

25

45

2.5

ovarian

FST

29

16

2.4

laid

LV

34

25

2.2

ovarian

LV

24

60

1.8

ovarian

LV

22

31

2

ovarian

LV

24

20

unknown

ovarian

LV

24

10

unknown

ovarian

LV

34

37

2

laid

LV

24

46

unknown

ovarian

LV

2.9

ovarian

LV

Nectophrynoides laticeps (Channing, Menegon, Salvidio and Akker, 2005) Nectophrynoides minutus Perret, 1972 Nectophrynoides paulae Menegon, Salvidio, Ngalason and Loader, 2007 Nectophrynoides poyntoni Menegon, Salvidio and Loader, 2004 Nectophrynoides tornieri (Roux, 1906)

Nimbaphrynoides occidentalis (Angel, 1943)

32.5

Poyntonophrynus dombensis (Bocage, 1895)

40

Poyntonophrynus fenoulheti (Hewitt and Methuen, 1912)

43

us

Nectophrynoides vestergaardi Menegon, Salvidio and Loader, 2004 Nectophrynoides viviparus (Tornier, 1905)

92

37

unknown

2

laid

FST

58

3000

2

laid

FST

Vandijkophrynus amatolicus (Hewitt, 1925)

Vandijkophrynus gariepensis (Smith, 1848) Vandijkophrynus robinsoni (Branch and Braack, 1996) Werneria bambutensis (Amiet, 1972)

M

Vandijkophrynus angusticeps (Smith, 1848)

553  554  555 

17

0.6

ovarian

MV

900

1.8

laid

FST

2000

1.8

laid

FST

2500

2.5

laid

FST

95

unknown

1.5

laid

FST

57

2000

unknown

laid

FST

483

2

ovarian

FST

629

1.5

ovarian

FST

35

2.5

219

laid

FST

te

38

41.2

Table 2a. ANOVA table for effect of body size on clutch size with clutch type as the treatment variable (interaction terms were not significant). Sum of Sq. Df F P Intercept <0.001 54.750 1 51.673 Female Body Size <0.001 210.568 1 198.736 Clutch Type 0.501 0.487 1 0.460 Residuals 56.156 53

Ac ce p

550  551  552 

d

Werneria tandyi (Amiet, 1972) Wolterstorffina parvipalmata (Werner, 1898)

160

an

60

Schismaderma carens (Smith, 1848)

547  548  549 

cr

Nectophrynoides asperginis Poynton, Howell, Clarke and Lovett, 1999 Nectophrynoides cryptus Perret, 1971

ip t

Mertensophryne usambarae (Poynton and Clarke, 1999)

Table 2b. Permutation ANOVA table for effect of body size on clutch size with reproductive mode as the treatment variable. Df R Sum of Sq. R Mean Sq. F P Female Body Size 1 170.387 170.387 179.674 <0.001 Reproductive mode 1 5.383 5.383 5.676 0.021 Residuals 51 48.364 0.948 Table 3a. ANCOVA table for effect of body size on clutch size with clutch type as the treatment variable (interaction terms were not significant). Sum of Sq. Df F P Intercept <0.001 2.479 1 31.024 Female Body Size 0.001 0.961 1 12.027 Clutch Type 0.132 0.188 1 2.347  

28

Page 28 of 32

Residuals

51

ip t

Table 3b. ANCOVA table for effect of body size on clutch size with reproductive mode as the treatment variable. Sum of Sq. Df F P Intercept <0.001 2.616 1 51.912 Female Body Size (FBS) <0.001 1.089 1 21.623 Reproductive mode (RM) 0.027 0.264 1 5.238 FBS*RM 0.024 0.272 1 5.399 Residuals 2.418 48 Table 4a. ANCOVA table for effect of clutch size on egg size with female body size and clutch type as covariates (interaction terms were not significant). Sum of Sq. Df F P Intercept 0.004 0.356 1 9.734 Clutch size <0.001 0.778 1 21.303 Female Body Size 0.150 0.078 1 2.148 Clutch type 0.056 0.141 1 3.864 Residuals 1.607 44

M

Table 4b. ANCOVA table for effect of clutch size on egg size with female body size and reproductive modes as covariates (interaction terms were not significant). Sum of Sq. Df F P Intercept 0.010 0.274 1 7.207 Clutch size <0.001 0.852 1 22.454 Female Body Size 0.067 0.134 1 3.537 Reproductive mode 0.159 0.078 1 2.057 Residuals 1.670 44

Ac ce p

565  566 

te

d

562  563  564 

an

us

559  560  561 

4.075

cr

556  557  558 

 

29

Page 29 of 32

B

M an

12

A

10 8 6

1000 1500 2000

2

0

4

500

C

ln(Clutch Size)

0

3.0 3.5 4.0 4.5 5.0 5.5 ln(Max. Female Body Size)

12

ce

0

10

Ac

5

10

20

pt

15

2

Number of Species

20

4

ed

6

30

25

8

ln(Clutch Size)

10

40

Figure1

0

10000

20000

Max. Clutch Size

30000

Page5.0 30 of 32 3.0 3.5 4.0 4.5 5.5

ln(Max. Female Body Size)

B

M an

1.5

A

3.0 3.5 4.0 4.5 5.0 5.5

C

1.0

1.5

ln(Max. Female Body Size)

0

1

2

3

4

Max. Egg Size (in mm)

5

−0.5

0

0.0

0.5

ln(Egg Size)

5

Ac

10

ce

pt

15

−0.5

Number of Species

ed

0.0

0.5

20

ln(Egg Size)

1.0

25

Figure2

Page5.0 31 of 32 3.0 3.5 4.0 4.5 5.5

ln(Max. Female Body Size)

0.0

0.3

−3 −2

ln(Clutch Size) Residuals −1

0

1

2 3

0.0

0.3

ln(Egg Size) Residuals −1.2 −0.9 −0.6 −0.3

0.6

A 0.6

pt

Ac ce

−1.2 −0.9 −0.6 −0.3

ln(Egg Size) Residuals

Figure3

B

−3 −2

32 of 32 ln(Clutch Size) Page Residuals

−1 0 1 2 3