viviparity


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Related to viviparity: territoriality, ovoviviparity

viv·i·par·i·ty

(viv'i-pār'i-tē),
The quality or state of being viviparous, that is, producing offspring that are living at the time of birth.
Synonym(s): zoogony

viviparity

(vĭv″ĭ-păr′ĭ-tē)
The ability to produce living young rather than producing young by laying an egg that hatches.

viviparity

the state of being viviparous.
References in periodicals archive ?
This is the time when mammalian viviparity had begun and two different types of viviparous systems using chorioallantoic and choriovitelline (yolk sac) placentas were established in the eutherians and marsupials, respectively (Figs.
Overall the conclusion is that although viviparity allowed lizards in the past to invade and adapt to live in cold environments, and was therefore a key trait for evolutionary success, it will now ultimately lead to multiple events of extinction.
Birth rings are formed as a response of the stress caused by changing placental viviparity to free-living lifestyle.
first discusses the compromises that have been made in evolution: sexual reproduction, viviparity, a hemochorial placenta, a long gestation period, and a reproductive strategy that includes high parental investment in very few offspring, as well as the factors of morphological adaptation for habitual bipedalism, increased brain size and elaboration, and secondary altriciality of the newborn.
Most freshwater bivalves, including families of the order Unionoida, and the two veneroid families Sphacriidae and Corbiculidae, exhibit ovoviviparity and viviparity to various degrees.
Brooding in Corbicula madagascariensis (Bivalvia, Corbiculidae) and the repeated evolution of viviparity in corbiculids.
The success of viviparity (live birth) in mammals requires the creation and maintenance of a uterine environment that accommodates and supports fetal growth and development, a means by which the mother provides adequate amounts of the substances upon which the growth and development of the fetus depend, and a means to terminate pregnancy at a time when offspring can survive outside the womb.
Some of these ephemeroid grasses hardly ever produce any seeds and instead reproduce vegetatively or by viviparity, forming bulbils within the inflorescences or in the leaf axils.
A new hypothesis for the evolution of viviparity in reptiles.
The recent evolution of viviparity in these starfish suggests that the factors promoting such changes in modes of development might be discovered in field studies of contemporary populations.