{
  "annotation_id": "4d5fc878-fe8e-412d-9dcf-48e567f08ddd",
  "date_created": "2026-03-02T18:00:28.470000Z",
  "date_modified": "2026-03-02T18:00:28.470000Z",
  "file_hash": "860adca5757e3fe82d28bc9020ac6fc628ad80dd5d1599af992147d406640b30",
  "private": false,
  "record": {
    "abstract": "If one goes backward in time, the number of ancestors of an individual\ndoubles at each generation. This exponential growth very quickly exceeds the\npopulation size, when this size is finite. As a consequence, the ancestors of a\ngiven individual cannot be all different and most remote ancestors are repeated\nmany times in any genealogical tree. The statistical properties of these\nrepetitions in genealogical trees of individuals for a panmictic closed\npopulation of constant size N can be calculated. We show that the distribution\nof the repetitions of ancestors reaches a stationary shape after a small number\nGc ~ log N of generations in the past, that only about 80% of the ancestral\npopulation belongs to the tree (due to coalescence of branches), and that two\ntrees for individuals in the same population become identical after Gc\ngenerations have elapsed. Our analysis is easy to extend to the case of\nexponentially growing population.",
    "arxiv_id": "physics/0003016",
    "authors": [
      "B. Derrida",
      "S. C. Manrubia",
      "D. H. Zanette"
    ],
    "categories": [
      "physics.bio-ph",
      "cond-mat",
      "q-bio"
    ],
    "journal_ref": "Jour. theor. Biol. 203 (2000) 303.",
    "title": "On the genealogy of a population of biparental individuals",
    "url": "https://arxiv.org/abs/physics/0003016"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "5bd9fc15-a422-42e9-a6a7-b29e9fef8130",
    "id": "arXiv Dataset IDs",
    "type": "Model",
    "variant": "snapshot-2026-03-01",
    "version": "0.1.0"
  },
  "user_id": 1000002
}