"Darwinian threshold" meaning in English

{
  "etymology_text": "Introduced by Carl Woese.",
  "forms": [
    {
      "form": "the Darwinian threshold",
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      "expansion": "the Darwinian threshold",
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
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      "glosses": [
        "A transition period during the evolution of the first cells, when genetic transmission moves from a predominantly horizontal mode to a vertical mode."
      ],
      "id": "en-Darwinian_threshold-en-name-kznYouoY",
      "synonyms": [
        {
          "word": "Darwinian transition"
        }
      ]
    }
  ],
  "word": "Darwinian threshold"
}

{
  "etymology_text": "Introduced by Carl Woese.",
  "forms": [
    {
      "form": "the Darwinian threshold",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "def": "1"
      },
      "expansion": "the Darwinian threshold",
      "name": "en-prop"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "categories": [
        "English entries with incorrect language header",
        "English entries with language name categories using raw markup",
        "English eponyms",
        "English lemmas",
        "English multiword terms",
        "English proper nouns",
        "English terms with non-redundant non-automated sortkeys",
        "English uncountable nouns",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "glosses": [
        "A transition period during the evolution of the first cells, when genetic transmission moves from a predominantly horizontal mode to a vertical mode."
      ],
      "synonyms": [
        {
          "word": "Darwinian transition"
        }
      ]
    }
  ],
  "word": "Darwinian threshold"
}