A General Model for the Scaling of Offspring Size and Adult Size

Daniel S. Falster; Angela T. Moles; Mark Westoby

doi:10.1086/589889

Latitudinal variation in Dendroctonus ponderosae (Coleoptera: Scolytidae) development time and adult size

The Canadian Entomologist ◽

10.4039/ent133375-3 ◽

2001 ◽

Vol 133 (3) ◽

pp. 375-387 ◽

Cited By ~ 67

Author(s):

B.J. Bentz ◽

J.A. Logan ◽

J.C. Vandygriff

Keyword(s):

Pinus Ponderosa ◽

Native Species ◽

Development Time ◽

Second Generation ◽

Dendroctonus Ponderosae ◽

Offspring Size ◽

Adult Size ◽

Southern Population ◽

Northern Population ◽

Generation Offspring

AbstractDendroctonus ponderosae (Hopkins) is widely distributed across western North America, feeding in at least 12 native species of Pinus L. (Pinaceae). We investigated the existence of heritable differences in two life-history parameters (adult size and development time) of D. ponderosae from a northern population (central Idaho, Pinus contorta Douglas ex Loudon) and a southern population (southern Utah, Pinus ponderosa Douglas ex P. and C. Lawson). We attempted to separate heritable from environmental effects by rearing individuals from both populations through two generations (F1 and F2) in a common standardized laboratory environment with a constant temperature. Two treatment effects were tested for in the F2 generation: (1) geographic location (source host) for F0D. ponderosae; and (2) the F2 brood host. We hypothesized that, if differences were observed and the F0 source host and region had a greater effect on F2 brood development time and adult size than did the host in which F2 brood were reared, a heritable factor related to the F0 parents was responsible. Time to emergence was significantly shorter for second-generation offspring of the northern population than for second-generation offspring of the southern population, regardless of the F2 brood host. Although both the F2 brood host and F0 source parents were significant in explaining differences observed in the developmental-time distribution of F2 brood, the F0 source effect was found to be much greater. Also, F2 males and females from southern source parents were significantly larger than F2 brood from northern source parents when reared in both F2 brood hosts. Geographic region and original host of F0 source parents had a significant effect on F2 offspring size, whereas the immediate food for F2 brood was not significant in explaining differences. These results suggest genetically based regional differences in D. ponderosae populations.

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Bigger mothers are better mothers: disentangling size-related prenatal and postnatal maternal effects

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.1225 ◽

2013 ◽

Vol 280 (1766) ◽

pp. 20131225 ◽

Cited By ~ 60

Author(s):

Sandra Steiger

Keyword(s):

Body Size ◽

Maternal Effects ◽

Maternal Care ◽

Genetic Effects ◽

Offspring Size ◽

Adult Size ◽

Burying Beetle ◽

Maternal Body ◽

Maternal Size

Despite a vast literature on the factors controlling adult size, few studies have investigated how maternal size affects offspring size independent of direct genetic effects, thereby separating prenatal from postnatal influences. I used a novel experimental design that combined a cross-fostering approach with phenotypic manipulation of maternal body size that allowed me to disentangle prenatal and postnatal maternal effects. Using the burying beetle Nicrophorus vespilloides as model organism, I found that a mother's body size affected egg size as well as the quality of postnatal maternal care, with larger mothers producing larger eggs and raising larger offspring than smaller females. However, with respect to the relative importance of prenatal and postnatal maternal effects on offspring growth, only the postnatal effects were important in determining offspring body size. Thus, prenatal effects can be offset by the quality of postnatal maternal care. This finding has implications for the coevolution of prenatal and postnatal maternal effects as they arise as a consequence of maternal body size. In general, my study provides evidence that there can be transgenerational phenotypic plasticity, with maternal size determining offspring size leading to a resemblance between mothers and their offspring above and beyond any direct genetic effects.

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The effects of adult length and arrival date on individual reproductive success in wild steelhead trout (Oncorhynchus mykiss)

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-158 ◽

2004 ◽

Vol 61 (2) ◽

pp. 193-204 ◽

Cited By ~ 33

Author(s):

Todd R Seamons ◽

Paul Bentzen ◽

Thomas P Quinn

Keyword(s):

Reproductive Success ◽

Oncorhynchus Mykiss ◽

General Trend ◽

Offspring Size ◽

Natural Setting ◽

Adult Size ◽

Steelhead Trout ◽

Arrival Date ◽

Affected Offspring ◽

Genetically Determined

To determine the relative importance of adult size and arrival date for reproductive success in a natural setting, we first genetically determined relationships between all spawning adult steelhead (Oncorhynchus mykiss) and juvenile offspring in four brood years and then tested hypothesized relationships between parents' phenotypes and the number and size of their juvenile offspring. Patterns of reproductive success varied among years, but in all cases, a few adults of each sex produced most of the offspring. The number of offspring showed a weak, positive relationship to the mother's size but not to her arrival date. Paternal reproductive success varied considerably but was only weakly associated with size in 1998 and weakly related to arrival date in 2000. In 1997, 1998, and 1999, the offspring of early-spawning females were larger at the end of their first and second summers in the stream; however, in 2000, both arrival date and length were positively related to offspring size. There was no general trend in offspring size in relation to paternal size or arrival date; however, paternal length affected offspring size in 1998 and male arrival date affected offspring size in 2000.

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