Correlation between life spans, modeling

Modeling for Biological Populations with Correlation between Life Spans of Siblings... 

Koch and Schaechter (K3) have pointed out a number of unsatisfactory features in use of cell age as an index or measure of cell structure. In particular they note that the model based on this predicts no correlation between the life spans of sister cells, whereas in fact these life spans are found to be correlated. Again, they note that the mass of cells at division (bacterial cells, at any rate) shows less spread about a mean value than does the age of cells at division. They also report that they have found that the mean size of bacteria, at division, changes in a regular fashion when cells are transferred to a medium in which growth rate and bacterial size are different. 

As mentioned previously, an important feature of this model is its ability to account for a correlation between the life spans of sister cells. The model which used age as an index of cell structure cannot do this. 

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