where [O.sub.j] = observed probability that a larva from sibship
j would become a carnivore morph when reared with siblings only, S = number of sibships
per tank (= 4), and [N.sub.j] = number of larvae from sibship
j per tank (= 2).
Eleven newborn nauplii from each of five sibships
were reared in each of two diets: (1) Cryptomonas sp.
However, in this and other experiments, it remains unclear to what extent observed genetic differences in seedling success reflect differences within versus among maternal sibships
. This issue is important because in the former case, natural selection would be strongest among siblings, while in the latter case selection would primarily be among maternal genotypes (Schmitt and Antonovics 1986).
There were no significant differences among maternal sibships
for any traits except emergence date, proportion emerging, and number of leaves.
There were no differences in cannibalism rates between the two sibships
Genetic variance was approximated by the analysis of differences among clones rather than sibships
in this study.
Thus, each iteration produces two full sibships
, which are each other's half sibs.
Each of the eight source populations (four of each subspecies) was represented by six maternal sibships
. Each sibship
consisted of 80 seeds (40 from each of two fruits) for dioecious plants and 40 seeds (20 from each of two fruits) for monoecious plants.
This constant requires information on relatedness within maternal sibships
(Falconer 1989), which may vary among populations.
We planted 50 seeds from each of 14 maternal sibships
in a random design with one seed per cell (3 x 3 cm and 4.5 cm deep) in each of 11 64-cell trays containing potting soil on 10 July 1989.
To assess within-population variation in germination percentage, field-collected sibships
from seven maternal plants were used.
Studies with plants predominately involve hand-planting sibships
in the field (c.f.