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Fish Reproduction - Anatomy & Physiology (view source)
Revision as of 11:32, 29 July 2008
, 11:32, 29 July 2008→Hermaphrodism
=== Hermaphrodism ===
=== Hermaphrodism ===
Hermaphroditic species can be either simultaneously hermaphroditic or sequentially hermaphroditic.
==== Simultaneously Hermaphroditic Species ====
* Each individual is both male and female at the same time
* Ripening of the gonads may be sequential to prevent unnecessary self fertilization.
==== Sequentially Hermaphroditic Species ====
* Any given individual is only one gender at a time, but can change gender when necessary.
* In sequentially hermaphroditic species all individuals are born as the same gender, this can be either male or female, but is fixed for the species.
* The gender change follows environmental cues that normally reflect the reproductive state of other nearby individuals of the same species.
* Species that are born male and change to female are called '''Protandrous''' (andros = male, proto = first)
* Species that are born female and change to male are called '''Protogynous''' (gyne = female, proto = first).
* Gender change normally accompanies a change in size to a larger individual.
** If the species is protandrous then the females are larger than the males
** If the species is protogynous then the males are larger than the females.
== Monogamy, Polygyny, Polyandry & Polygynandry ==
== Monogamy, Polygyny, Polyandry & Polygynandry ==