Distinguishing Counts of Ancestors

Question

I am trying to refer to a number of ancestors in two ways, and I need two terms or even two adjectives for "ancestors" that will distinguish one from another.

The case I am interested in is where there is pedigree collapse, where one person is an ancestor of the proband in multiple ways.

For example, the following simple pedigree of Cleopatra (from Wikipedia)

The diagram identifies 13 ancestors.

In genealogy, the typical method of denoting ancestors is through a pedigree chart, where each generation of the chart shows both parents for each person of the previous generation and thus always grows in a binary manner, with 1, 2, 4, 8, 16, ... ancestors listed at each generation. Of course, not all the ancestors are always known and some of the ancestors may repeat.

So the above Cleopatra tree will then be shown as:

        - Ptolemy V Epiphanes
      - Ptolemy VIII Physcon
        - Cleopatra I Syra
    - Ptolemy IX Latyros
        - Ptolemy VI Philometor
      - Cleopatra III
        - Cleopatra II
  - Ptolemy XII Auletes
        - Ptolemy V Epiphanes
      - Ptolemy VIII Physcon
        - Cleopatra I Syra
    - Cleoptra IV
        - Ptolemy VI Philometor
      - Cleopatra III
        - Cleopatra II
- Cleopatra VII Philopator
        - Ptolemy V Epiphanes
      - Ptolemy VIII Physcon
        - Cleopatra I Syra
    - Ptolemy X Alexander I
        - Ptolemy VI Philometor
      - Cleopatra III
        - Cleopatra II
  - Cleopatra V
          - Ptolemy V Epiphanes
        - Ptolemy VIII Physcon
          - Cleopatra I Syra
      - Ptolemy IX Latyros
          - Ptolemy VI Philometor
        - Cleopatra III
          - Cleopatra II
    - Berenice III
          - Ptolemy V Epiphanes
        - Ptolemy VIII Physcon
          - Cleopatra I Syra
      - Cleopatra Selene I
          - Ptolemy VI Philometor
        - Cleopatra III
          - Cleopatra II

This shows 38 ancestors, but there are only 13 individuals, many of whom are repeated multiple times due to the inbreeding.

My question is I want to refer to the two different counts of ancestors. So what would be the best terminology to use to say:

I have 13 __________

I have 38 __________

Answer 1

For your use, I would employ 'predecessor',

a. A person who comes before another person in time; an ancestor, a forefather, a forebear.

For the sense of 'individual ancestors',

I have 13 predecessors.

Or, similarly, I might use 'progenitor',

1. A person from whom another is descended; an ancestor, a forefather; a parent.

For that same sense:

I have 13 progenitors.

For the more general sense of 'ancestors', understanding your use of 'ancestor' to mean 'a position in the genealogical structure', I might use 'ascendant',

8. One who precedes in genealogical succession; an ancestor; a relative in the ascending line, whether lineal, as father, mother, or collateral, as uncle, great-uncle.

So in your second example:

I have 38 ascendants.

While the context may make the distinctions between the terms you use evident, it might also be advisable to make explicit the distinction between 'predecessors' or 'progenitors' in the sense of 'individual ancestors' and 'ascendants' in the sense of 'a position in the genealogical tree'.

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Note also that, depending on the purpose or nature of the genealogy, I might use 'propositus' rather than 'proband'. This is because the sense of 'proband' is usually restricted technically, as

Med. and Genetics. The individual with whom the investigation of a family for a genetic disorder or other inherited trait begins; the first member of a family to be diagnosed with a hereditary disease or trait.

'Propositus', on the other hand, is not restricted in technical use to a primary ancestor considered with reference to genetic disorders or inherited traits, but is more generally applied to any individual viewed as the basis of a genealogy:

1. A person from whom a line of descent is derived; an individual from whom family relationships are calculated or on whom a genealogy or pedigree is based.

(All definitions from OED Online. Phrase emphasis in definitions of 'ascendant' and 'proband' is mine.)