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Research draft

viviparity

vr.tr.viviparity · ACT.PRC

Let an agent explain viviparity and its forms, relay its distribution and evolution from zoological sources, describe mechanisms of nourishment, and distinguish viviparity from oviparity, ovoviviparity and live birth in plants.

Thing Registry Activities and processes

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify

Researched by: Claude

Purpose and description

Let an agent explain viviparity and its forms, relay its distribution and evolution from zoological sources, describe mechanisms of nourishment, and distinguish viviparity from oviparity, ovoviviparity and live birth in plants.

A mode of animal reproduction in which the embryo develops inside the body of the parent and is born live, rather than hatching from an egg laid outside, found in nearly all mammals and independently evolved in many reptiles, fishes, amphibians and invertebrates, ranging from simple retention of eggs to placental nourishment, and including specialised forms such as adenotrophic viviparity in tsetse flies where larvae are fed by glandular secretions; the Sanskrit term jarayuja names the viviparous class of beings in Indian classification.

What it is for: Not applicable; a reproductive mode.

It can be explain forms; relay distribution and evolution; describe nourishment mechanisms; distinguish from oviparity.

Distinguishing features

Internal development

Live birth

Multiple independent origins

Range of nourishment

What it looks like

Not a visible object; live birth of developed young.

Physical character

independent origins in squamate reptiles: over 100 count - estimates

viviparous mammals: all except monotremes note

How it is recognised

Live birth after internal development

Placental viviparity, lecithotrophic viviparity, adenotrophic viviparity in tsetse flies

Oviparity lays eggs; ovoviviparity retains eggs without nourishment; vivipary in plants is seed germination on the parent

Related models

is a kind of - in registry terms

animal reproduction

is contrasted with - egg laying

oviparity

is contrasted with - egg retention without nourishment

ovoviviparity

involves - in placental forms

placenta

In practice

Families and kinds

placental viviparity in therian mammals

viviparity in squamate reptiles

viviparity in sharks, rays and some bony fishes

viviparity in amphibians such as some caecilians and salamanders

adenotrophic viviparity in tsetse flies and related insects

viviparity in other invertebrates such as some scorpions and aphids

Standards and regulation

No regulation; zoological terminology conventions

Failure modes and hazards

Confusing viviparity with ovoviviparity

Assuming viviparity is limited to mammals

Mixing the plant sense of vivipary

Also called

jarāyujaadenotrophic viviparity

Where this came from

wikidata · CC0 1.0

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.

Understand What viviparity is.

Science.

Definition

Definition.

Definition

Definition.

  1. What is viviparity, and how does it differ from oviparity and ovoviviparity? definition
  2. Is the question about animal viviparity or plant vivipary? boundary

Forms

Forms.

Forms

Forms.

  1. What are placental, lecithotrophic and adenotrophic viviparity? definition
  2. Which entry fits the specific form? action
Biology Distribution and mechanisms.

Science.

Distribution

Distribution.

Distribution

Distribution.

  1. Which animal groups are viviparous, and how does viviparity occur in reptiles, fishes, amphibians and insects? provenance
  2. Which references are standard? provenance

Mechanisms

Nourishment mechanisms.

Mechanisms

Mechanisms.

  1. How are embryos nourished, from yolk to placentas and glandular secretions? provenance
  2. Which sources are cited? provenance
Evolution Evolution.

Science.

Origins

Origins.

Origins

Origins.

  1. Why has viviparity evolved so many times, and what hypotheses explain it, with positions attributed? provenance
  2. Which entry fits the evolution of reproduction? action

Tradeoffs

Costs and benefits.

Tradeoffs

Tradeoffs.

  1. What are the costs and benefits of viviparity compared with egg laying? provenance
  2. Which entry fits life history theory? action
Context Culture and classification.

Context.

Classification

Classifications.

Classification

Classification.

  1. How do traditional classifications such as the Indian jarayuja treat viviparous beings? provenance
  2. Which entry fits Indian classification of beings? action

History

History.

History

History.

  1. How did Aristotle and later naturalists classify modes of reproduction? provenance
  2. Which entry fits the history of zoology? action

What the second pass must settle

  • Should ovoviviparity and adenotrophic viviparity be separate entries?
  • How should zoological sources be linked?
  • How should the Sanskrit classification term be linked?