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-====== Sex, death and silence in hawaiian crickets ======
-Wiki of the practical exercise of the [[http://www.ictp-saifr.org/?page_id=4634|III Southern-Summer School on Mathematical Biology]].
-Here you find the exercise assigment and the group's products.
-If you are a group member login to edit this page, create new pages from that, and upload files.
-===== Assignment =====
-Males of many crickets species use calling songs as sexual signals.
-Females locate and select singing males even in the dark of
-night, and can be very choosy in their mating preferences.
-This is indeed the business as usual in
-many populations of the Pacific field cricket, //Teleogryllus
-  oceanicus//, but not in Hawaii, where there is a deadly enemy, the fly
-//Ormia ochracea//. The fly is a parasitoid that uses song to find
-and lay larvae on the singing males.
-The larvae then find their way inside the bodies
-of the unfortunate singers and
-feast on their internal tissues, eventually killing the host.
-In 2006 Marlene Zuk and collaborators documented the rapid spread of
-a silent male morph in a population of //Teleogryllus
-  oceanicus// in Kauai Island, Havaii.
-The morph is called 'flatwings'
-as it lacks the wing structures used to produce songs.
-The change is caused by a single gene in the sexual chromosome
-of males.
-Flatwing males escape from the parasitoid, but also are not found
-by females. They have a 'satellite' sexual behavior -- to
-attempt to mate females that are attracted by calling males.
-Currently about 90% of the male crickets in Kauai were
-of the flatwing morph. Such a huge proportion of silent satellites
-rely on the few remaining singing males to reproduce.
-==== Questions ====
-This is a well-documented case of  persistence of a maladaptative
-sexual character due parasitoid pressure. The genetic, evolutionary and behavioral
-patterns are far more explored than the demographic and/or population
-genetics dynamics of the system.
-The basic question is to propose a mathematical model that portrays this
-dynamic in a simple but biologically realistic way. Given that, you
-can investigate the dynamic behavior of the model, as well as to check
-which values of the parameters ensue persistence of both morphs and
-the parasitoid in the long run. Further well-grounded insights are welcome.
-=== Hints ===
-  * A key feature of this system is the inheritance mechanism of the flatwing gene.
-  * Another key information is the degree of specialization of the parasitoid.
-  * The published information about the system is plenty of useful biological information. It was mainly produced by a single research group, so its is coherent and  well circumscribed, and can be fully appreciated.
-==== Basic readings ====
-Marlene Zuk, John T Rotenberry, and Robin M Tinghitella. Silent night: adaptive disappearance of a sexual signal in a parasitized population of field crickets. Biology Letters, 2(4):521–524, 2006.
-RM Tinghitella. Rapid evolutionary change in a sexual signal: genetic control of the mutation ’flatwing’ that renders male field crickets (//Teleogryllus oceanicus//) mute. Heredity, 100(3):261–267, 2007.