User:RobertDRosner/sandbox

Areas of Improvement
Protandry:

- Use Book Section from Encyclopedia of Animal Behavior and Cognition on Protandrous Hermaphroditism to sure up definition (1) √

- Add information about the spectrum of types of protandry √

- add image to article (if possible) √

- Add Example in Lysmata Shrimp (6) √

Protogyny:

- Sure up introduction with better definitions and more citations

- Add citation for blue-headed wrasse √ and other examples √

- Ultimates causes section:

- Reorgranize √

- Rarity section needs to be organize

- Proximate causes:

- expand with other physiological causes

- needs more work, Physiological Causes, explains mechanisms

- More info about Genetics is required

- Botany √

- Need to add information about Protogynous hermaphroditism (Epiactis prolifera, which is mentioned on talk page)

(https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1467-2979.2007.00266.x)

Changes Made
Lead Section for Sequential Hermaphroditism:

In particular, a sequential hermaphrodite produces eggs (female gametes) and sperm (male gametes) at different stages in life.

Added Intro to Protandry:

In general, protandrous hermaphrodites are animals that develop as males, but can later reproduce as females. However, protandry features a spectrum of different forms, which are characterized by the overlap between male and female reproductive function throughout an organism's lifetime:


 * 1) Protandrous sequential hermaphroditism: Early reproduction as a pure male and later reproduction as a pure female.
 * 2) Protandrous hermaphroditism with overlap: Early reproduction as a pure male and later reproduction as a pure female with an intervening overlap between both male and female reproduction.
 * 3) Protandrous simultaneous hermaphroditism: Early pure male reproduction and later reproduction in both sexes.

Furthermore, there are also species that reproduce as both sexes throughout their lifespans (i.e simultaneous hermaphrodites), but shift their reproductive resources from male to female over time.

Protandrous examples
Protandry is uncommon, but does occur in a widespread range of animal phyla. In fact, protandrous hermaphroditism occurs in many fish,  mollusks,  and crustaceans, but is completely absent in terrestrial vertebrates or insects.

Other examples of protandrous animals include:


 * The Platyctenida order of comb jellies. Unlike most ctenophores, which are simultaneous hermaphrodites, Platyctenida are primarily protandrous, but asexual reproduction has also been observed in some species.
 * The flatworms Hymanella retenuova. (Add more after ILL is received.)


 * The Lysmata genus of shrimp perform protandric simultaneous hermaphroditism where they become true hermaphrodites instead of females. During the "female phase," they have both male and female tissues in their gonads and produce both gametes.

Protogyny:

Protogyny is the most common form of hermaphroditism in fish in nature. About 75% of the 500 known sequentially hermaphroditic fish species are protogynous and often have polygynous mating systems. In these systems, large males use aggressive territorial defense to dominate female mating. This causes small males to have a severe reproductive disadvantage, which promotes strong selection of size-based protogyny.

Blue-headed wrasses begin life as males or females, but females can change sex and function as males. Young females and males start with a dull initial-phase coloration before progressing into a brilliant terminal-phase coloration, which has a change in intensity of color, stripes, and bars. Terminal-phase coloration occurs when males become large enough to defend territory. Initial-phase males have larger testes than larger, terminal phase males, which enables the initial-phase males to produce a large amount of sperm. This strategy allows these males to compete with the larger male, who is able to guard his own mate.