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Genealogy is nothing new. For centuries, people have researched their family histories, documenting the links they find. A family tree is a way to visualize that family history in an organized chart. Family trees are often used as displays to show family heritage, but they're also useful for informational purposes like learning about your family's medical history. Family trees follow a typical structure, but the appearance can vary somewhat depending on the information included and type of tree.
Basic Structure of a Family Tree
Family trees show the ancestors of a single person. The tree branches down to show that person's kids and subsequent generations. All members of one generation appear at the same level as one another, so you can easily see the organization. If your grandparents are the oldest generation, all of their kids, which would include your parents, aunts and uncles, go on the next tier, all at the same level. You, your siblings and your cousins go on the next tier. Family trees can show as many generations as desired, but the size of the tree can quickly become difficult to put on one diagram as the family branches out.
The oldest generation on the tree can appear at the top or at the bottom, depending on how the tree is organized. If the tree starts at the bottom, you can think of the person as the roots of the tree. The subsequent generations build up toward the top of the chart, forming a widening tree structure. Some family trees use a reverse structure, with the oldest generation at the top. Each subsequent generation appears one tier lower.
Sometimes a family tree uses a horizontal approach. In this method, you would see the oldest generation on the left side of the chart. That person's kids appear to the right. This continues with the youngest generation on the right side of the chart.
Types of Family Trees
While the standard family tree method uses the layered approach with each generation on a separate line, some other types of family trees look a little different. These options may be better for certain family situations or may create a more pleasing presentation.
Explore the following types and how they look:
- Fan chart: This method looks like a circle, half circle or quarter circle with the oldest generation in the center. You'll see subsequent generations in the circles spreading outward from the center.
- Hourglass tree: This type of tree looks like an hourglass with one person at the center. That person's ancestors branch out above him, and his descendants branch out below him.
- Pedigree chart: A pedigree chart is typically arranged like a standard family tree. The main difference in appearance is the use of symbols to represent different people and relationships. You'll usually see three to five generations on this type of chart.
Symbols Used on Family Trees
While a basic family tree may use boxes to hold all names, more detailed charts use specific symbols to represent different genders and relationships. Genograms and pedigree charts incorporate symbols and different types of lines to give more detail about relationships.
Gender is one of the basic symbols. Males appear as squares, and females are represented by circles. Someone of an unknown gender goes in a diamond. If someone is pregnant, the baby can be represented by a square, circle or diamond with a "P" inside. A triangle represents a pregnancy loss, whether it was a miscarriage, stillbirth or abortion. If someone is deceased, the gender symbol has a diagonal line through it.
Lines show the relationships between people. Solid horizontal lines connect married couples. If the couple has kids, a vertical line extends from that line with another horizontal line at the end. Additional vertical lines extend downward to represent their kids, with the gender symbol at the end.
Different types of lines help further detail relationships. If you see two diagonal lines on the line connecting spouses, you know that the couple divorced. A blue dashed line shows an engagement. A red zigzag line shows a hostile relationship, while a blue zigzag line indicates abuse. You might also see color inside the gender symbol for some people. Different colors represent different types of health conditions, such as heart disease, cancer or diabetes.
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