The Contextual Family Tree

     

1. Vis for genealogy    2. Vis Nuclear families    3. Contextual Family Tree     4. Vis Consanguinity

The Nuclear family timeline, described on the previous page, provides a detailed overview of the genealogical records of two spouses and their offspring. The natural next step was to devise a method to represent a family tree that incorporates detailed information about each nuclear family.

We have proposed the Contextual Family Tree (CFT) method published in the Information Visualization Journal. 

The image below shows how a CFT encodes the information about each nuclear family. The two spouses are represented by the two boxes temporarily aligned from the bottom by the most recent known date. Thus, comparing boxes positions only makes sense between two spouses, while comparing boxes heights is meaningful between any two individuals. An individual with a taller box lived longer than another individual with a shorter box. 

In the picture, the husband was born before his wife. Below their names, the line with the double ring indicates their wedding date. The absence of the line would indicate that the date is unknown and the absence of the double ring indicates that there is no information if there was a marriage. The dashed line and the crossed double-ring show similar details on divorces.

In the example, it is known that the husband has died, but the date is unknown. That is indicated by the dotted line at the bottom and by the label 'd. ?'.

The small boxes below the two spouses' boxes indicate their offspring ordered from left to right by date of birth and colored by gender. The shape of the small boxes encodes the information known about each child, from 'no further news' to knowledge about marriages and offspring.

A CFT has a representation like this for each family, representations that are connected by an arrow indicating whose child of a couple corresponds to a spouse in another family.

The figure below represents the Contextual Family Tree of my parents. My mother, Maria Cabral, has a taller box than my father, and it starts before, meaning that she was born before him and died after. The labels indicate their dates of birth and death and their ages at their death. The small boxes indicate that they had five children, four girls and a boy. The second child died an infant, and the other four had offspring.

The arrowed arc connecting my father indicates that he was the third of three children. The elder was a girl that lived until adulthood but did not marry or have offspring. My mother was the sixth of twelve children, two of whom died as infants. Three of her sisters and one brother did not have offspring.

The image provides a general overview of my ancestry.  Most of the wives lived longer than their husbands, although there are some cases where the opposite happens. For example, my great-great-grandfather, Gaspar Aguiar, was older than his wife, Benilde Melo, and died fifteen years later. There are only four individuals for whom the dates are unknown, the spouses, Domingos Guimarães and Ana, and José Sequeira and Francisca. 

Both my grandfathers were older than their wives and died well before their wives. Similarly, all four great-grandfathers were older than their wives, and three of them died considerably earlier than their wives.

Looking at the great-great-great-grandparents, António Borges had seven children, but we do not have information about the first five. José Castanheira had nine, but we only have information about one. José Valdez had ten children, but only two had offspring. João Macedo was quite old when he married Claudina Macedo. The small dash on the left side of João's boxes above their wedding line indicates that their marriage was his second. Interesting is also the case of António Aguiar, who died at 44 but had twelve children. We have seen in the ages plot that he married at eighteen.

The following image shows the CFT for my wife and me. If there is consanguinity in a family, some individuals have multiple occurrences in their tree. The figure shows the case of Constantino Cabral and Maria Coelho, our common great-great-grandparents. This couple is represented only once, having two of their children with arrows connecting to individuals in the subsequent generation; Francisco Cabral, the third son, is my great-grandparent, while Afonso Cabral, the eighth son, is my wife's great-grandparent.

We believe a CFT provides a nice overview of consanguinity in the ancestry of the two root individuals. Since a CFT is a design that works well for up to five generations, it has limitations for analyzing consanguinity on farther generations; we have studied visualization methods for consanguinity analysis in larger trees. In the next page we describe VisAC, our Visual Tool for Consanguinity Analysis.