Quantitative genetics and the evolution of ontogeny: I. Ontogenetic changes in quantitative genetic variance components in randombred mice

Abstract

We report the results of an ontogenetic analysis of quantitative genetic variance components with two replicates drawn from the randombred ICR strain of mice. A total of 432 mice from 108 full-sib families raised in a cross-fostering design were used to estimate direct effects heritability, maternal effects, and environmental effects for weight, head length, trunk length, trunk circumference, and tail length at 17, 24, 31, 38, 45, 52, 59, and 66 days of age. There was no significant difference in heritability between the replicates. Heritabilities either stayed more or less constant with age at about 030 (weight, trunk length, trunk circumference) or increased slightly with age (head length, tail length). Maternal effects decreased with age from a maximum of about 050 at weaning to about 015 at age 66 when growth was nearly complete. Environmental effects increased in relative importance during ontogeny.

On the Relationship between Ontogenetic and Static Allometry

“…Therefore, the downward bias of the static allometric slope due to measurement error should be on the order of 1%-2% (Hansen and Bartoszek 2012) and should not strongly affect differences between ontogenetic and static allometry as well as the changes in static allometry during ontogeny. For the mouse data, the repeatability of the trunk length was relatively high (0.9 on average) but tended to decrease in the measurements done at an older age (table 3 in Cheverud et al 1983). This could generate a downward bias of the static allometric slope of ∼10% during ontogeny.…”

“…The first data set comprises data on ontogenetic allometry of the caudal fin length collected on female guppies (Poecilia reticulata) from three different populations maintained in captivity. The second data set comprises data on ontogenetic allometry of head length and tail length of mice (Mus musculus) bred in captivity (Cheverud et al 1983;Cheverud and Leamy 1985). These organisms differ in their growth pattern, fish having indeterminate growth while the growth of mice ceases after ∼12 weeks.…”

“…Five live-body traits were measured with a caliper: head length, head breadth, ear length, trunk length, and tail length. However, two of these traits showed poor repeatability (ear length and head breadth; table 3 in Cheverud et al 1983). We therefore chose to analyze the allometric relationship between trunk length, as a measure of body size, and head length and tail length.…”

Immune function across generations: integrating mechanism and evolutionary process in maternal antibody transmission

“…For example, females may influence offspring phenotype and survival through mate choice, selection of oviposition sites and offspring provisioning (for reviews see : Bernardo 1996;Mousseau & Fox 1998a). Maternal effects generally have their greatest impact early in development and then decline as offspring mature (Cheverud et al 1983;Price 1998;. However, because mortality and thus selection are often greatest during early development (Rossiter 1996), even maternal effects of short duration may have important evolutionary consequences.…”

The formation of fluctuating asymmetry during individual development of Вetula pendula

“…Асимметрия отдельных признаков или их комплекса оценивается для особи, находящейся на определенной стадии развития, а для ее органов -в конкретный период морфогенеза. Однако в зависимости от возраста или стадии морфогенеза величина и изменчивость многих признаков может значительно меняться, так же как само качество особи со временем не остается постоянным (Cheverud et al, 1983;Leung, Forbes, 1997;.…”