The F2 generation (progeny of the crossing of two F1 individuals) affords the first opportunity for selection in pedigree programs.
This could be a possible source of bias between groups due to the opportunity for selection and different baseline characteristics.
From the records they had, the researchers could not tell which traits were being selected for, but the variation in the number of offspring from zero to 17 indicates there was a large opportunity for selection to occur.
A final opportunity for selection was the North-South inter-island match on 3 June 1905 after which, 25 players were selected for the team, and an additional two were added prior to the team's departure to Britain.
We also estimated the opportunity for selection on female fecundity and lifespan.
First, we estimated the overall constraint on total selection between the wealth classes by estimating the opportunity for selection (variance/mean2) on maternal fitness across wealth classes [41].
While mass treatment programs can be effective [5] they can also provide an opportunity for selection and development of drug resistance in scabies mites.
We found higher opportunity for selection and stronger selection on earlier age at first reproduction among the mothers of the poorest wealth class compared to wealthier mothers.
First, we documented the overall constraint on selection for female life-history traits between the wealth classes by estimating the opportunity for selection, which measures variance in fitness [25], [28], for each wealth class.
Estimating the opportunity for selection on two major female fitness components, i.e., on fecundity (Ifec) and longevity (Ilong), suggested similar trends as above between the wealth classes, but these differences were not statistically significant (Table 1).
Moreover, our analyses suggest that lack of variation is not what limits adaptive evolution in the brambling because parasitized and non-parasitized populations show the same variance in egg color even though there should be a strong opportunity for selection to increase variance in parasitized host-populations.
