vivipary: one construct, many systems

In botany, vivipary is the condition in which seeds germinate while still attached to the parent plant, skipping the usual dormant, desiccated, dispersable stage; in true vivipary, seen classically in mangroves, the embryo grows continuously into a seedling before dropping. Farnsworth's 2000 The ecology and physiology of viviparous and recalcitrant seeds links vivipary to the loss or suppression of abscisic-acid-mediated dormancy and to environments where immediate establishment pays off. The referent is a reproductive strategy that forgoes a resting propagule in favour of a precocious offspring developed on the parent, the same logic that, in animals, is called live birth.[1]

Unit

Whether and how far the embryo develops into a seedling before leaving the parent

Recovery means

Not applicable

Measured by

Assessed by the degree of pre-dispersal germination and the loss of seed dormancy and desiccation tolerance

In zoology, viviparity is the reproductive mode in which offspring are retained and develop inside the mother and are born as live young, rather than being laid as eggs that complete development outside the body (oviparity). Blackburn's 2006 Squamate reptiles as model organisms for the evolution of viviparity uses lizards and snakes (in which live-bearing has evolved repeatedly from egg-laying) to study how and why the transition occurs, often in cold climates where egg retention keeps embryos warm. The referent is a mode of bearing offspring, classified by egg retention and maternal provisioning, and it is the same construct as a plant's viviparous seed carried over into the animal kingdom.[2]

Unit

Whether offspring are retained and nourished internally and born live rather than laid as eggs

Recovery means

Not applicable

Measured by

Classified by egg retention, placentation or matrotrophy, and the developmental stage at birth