The concept of canalization was used by Waddington (66) in the context of developmental
biology. He emphasized two important points in the develop-ment of higher organisms. First, …

During the long-term population study of the Great Tit, all nestlings were ringed and most
parents were identified. This allows the construction of family-trees. In an island population of …

Ecologically important characters in birds, such as clutch size, date of laying and body size,
vary within and between populations and species. The mean values of these characters are …

About 40% of the population variation in the initiation dates of first clutches within years is
genetically determined. The onset of laying, which is determined by the female, is not …

Eight isofemale lines of Drosophila melanogaster were raised at four temperatures and at
four yeast concentrations in their food. Temperature and food show a significant interaction in …

We have analysed data on weight and tarsus length collected during a long-term study of
natural populations of Great Tits to evaluate the relative importance of genetic variation in body …

Timing of puparium formation in Drosophila melanogaster is set by reaching a critical stage
at which larvae attain the ability to pupariate. This critical stage is reached at a relatively …

In the mutant ciD of Drosophila melanogaster the relative length of the 4th vein was used as
a quantitative character. Divergent selection during 30 to 40 generations for long and short …

Genetic and environmental variation in clutch size of the great tit (Parus major) Page 1
Genetic and environmental variation in clutch size of the great tit (Parus major) Van Noordwijk …

Length and breadth of eggs were measured in ringed populations of the Great Tit. During a
part of the study volume and weight were also measured, but this did not give additional …