Beyond the value of establishing where you and your ancestors came from, family trees can have practical uses too. Establishing lineage can sometimes impact inheritance, which can be fractured or changed by war, disaster, disease, immigration and other life events. Family trees establish rights of inheritance and rights to property, and they can be critical to proving or disproving important questions of law. Consider all of the families parted during World War 2, and all of the land disputes in Europe that were settled only by establishing family trees. While many are unlikely to find a surprise fortune or an aristocratic title in their family trees, you’ll often discover fascinating facts about what your relatives did and thought.

How family trees work

There are a number of ways to construct a family tree. Using a service like Ancestry.com (opens in new tab) you can trace a male line - or a surname - from now to as far back as possible, or you can create a family history that fans out like a great tree that begins with your parents and include cousins, aunts, uncles and grandparents as far back as you can trace. These days, there are some wonderful family tree software programs that can help you make any kind of family tree electronically, which makes the whole process much easier. You can even print them out to show relatives, or to create unique decorations in your home, if you value where you’ve come from. In many cases, you won’t be able to go back more than a few generations (or you might find it too difficult to press on) but for those who are really interested in getting into the history or lineage of a family, there are a few more dedicated options. One of the most effective ways to get deeper into this is via a DNA testing kit (opens in new tab), which will give you the data you need to really trace your bloodline back for many generations. It can take some real detective work to accurately pull your family tree back as far as you can go. Knowing who your grandmother and great-grandmother were is one thing; finding out who their great-grandparents were requires a lot of note-taking, fact-checking and a willingness to fail. Sometimes you so want the answer to be there, but there’s just not enough evidence to back it up, and the temptation to make assumptions and take half-truths as fact is very real.

More contemporary uses of family trees

Family trees also help medical professionals answer questions. As genetics get more sophisticated, researchers, epidemiologists and scientists of all kinds may find valuable clues to curing disease embedded in family trees. You might also need to establish a family tree if you have a genetic disease, or to see how likely you are to pass on a disease to your children. If your family and your spouse’s family carry a gene for cystic fibrosis, for example, you will have a high likelihood of passing that disease on to your children. Knowing what medical problems are in your family tree can help you make important decisions, and could potentially save your life if you know to get treatment early. You might be looking for a lost cousin, or trying to prove that you’re the rightful heir to a small island off the west coast of Ireland, or you may want to win a bet with your buddy that you really are the great-great-great grandson of Johnny Appleseed. Whatever you’re looking for in your history, the family tree format can help you discover or disprove it. With so many tools, tutorials and how-to articles available, you can create an accurate family tree that will pass muster with any genealogist.

What is a Family Tree and why is it important  - 23