page_title: Family tree
section_title: Ahnentafel
hierarchical_section_title: Family tree / Family history representations / Ahnentafel
caption_attribution_description: English: An example of a typical family tree, using data from the famous Kennedy family of the United States.
context_page_description: A family tree, or pedigree chart, is a chart representing family relationships in a conventional tree structure. The more detailed family trees used in medicine and social work are known as genograms.
context_section_description: An ahnentafel (German for "ancestor table") is a genealogical numbering system for listing a person's direct ancestors in a fixed sequence of ascent: 
  Subject (or proband)
  Father
  Mother
  Paternal grandfather
  Paternal grandmother
  Maternal grandfather
  Maternal grandmother
  and so on, back through the generations. Apart from No. 1, who can be male or female, all even-numbered persons are male, and all odd-numbered persons are female. In this scheme, the number of any person's father is double the person's number, and a person's mother is double the person's number plus one. This system can be displayed as a tree:
caption: An ahnentafel family tree, showing three generations of the Kennedy Family
exif: {"Image ImageWidth": "1778", "Image ImageLength": "1333", "Image BitsPerSample": "[8, 8, 8]", "Image PhotometricInterpretation": "2", "Image Orientation": "Horizontal (normal)", "Image SamplesPerPixel": "3", "Image XResolution": "200", "Image YResolution": "200", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS5.1 Macintosh", "Image DateTime": "2012:01:03 15:50:59", "Image ExifOffset": "232", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "382", "Thumbnail JPEGInterchangeFormatLength": "3938", "EXIF ExifVersion": "0221", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "936", "EXIF ExifImageLength": "551"}