Offspring performance can be influenced by carry-over effects from earlier generations. For instance, nutritional conditions experienced by (grand)mothers may influence the birth weight of their daughters’ children. Although similar or related examples are plenty in literature, I have not encountered (detailed) studies on how temperatures experienced in embryonic stages might influence individual development in subsequent life-stages.
In recent study Macqueen et al. (2008) investigated how temperatures experienced in early egg stage influenced the subsequent number and diameter of muscle fibers in the Atlantic salmon. By exposing eggs to 2, 5, 8 or 10°C at egg stage and scoring the muscle phenotypes at an age of ca 3 years they found that fish exposed to + 5°C developed highest muscle fiber density. There were also temperature effects on initial growth of the fish so as that fish from +2 and +5°C degree treatments started from smaller size, but caught up their siblings from the warmer treatments later on.
It is interesting to think that the adult performance of salmons can be to some degree programmed by temperatures experienced during very early life. Namely, it is not difficult to imagine that observed differences in muscle fiber number may translate to differences in – for instance – ability to escape predators or to catch prey.
Given that it is the mother who decides where the eggs are laid, I guess these effects could be classified as environmental maternal effects.
Macqueen DJ et al. 2008. Temperature until the ‘eyed stage’ of embryogenesis programmes the growth trajectory and muscle phenotype of adult Atlantic salmon. Biology Letters 4:294-298.
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Here is another interesting study about body building in salmons. They show that the heritability of the muscle fiber density and number is moderate (0.3-0.5), and that there is a strong negative genetic correlation between fat content and muscle fiber density/number. However, this correlation does not show up at phenotypic level – too much environmental noise. Hence, by selecting for low fat content, one should see a positive response in muscle fiber number and density too.
Vieira, V. L. A., A. Norris and I. A. Johnston 2007. Heritability of fibre number and size parameters and their genetic relationship to flesh quality traits in Atlantic salmon (Salmo salar L.). Aquaculture 272:S100-S109.