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Types

• Asexual • Sexual • Sexual vs. asexual – costs associated with sexual but benefits (“lottery” model)

Asexual fission

• Fission • budding, • • Fragmentation- the body of the parent breaks into distinct pieces, each of which can produce an . Planarians exhibit this type of reproduction. • Regeneration- a piece of a parent is detached, it can grow and develop into a completely new individual. exhibit this type of reproduction.

budding Parthenogenesis • in , where growth and development of occurs without fertilization by a male (, , some , )

1 Broadcast spawning

• One of the • Broadcast spawning most common • Live forms of reproduction • systems in the oceans • and are – Sequential released into the water – Simultaneous column and are fertilized by neighbors • Often it is synchronous

fertilization Live birth in

Anadromous fishes

2 Mating systems in sexual smoltification reproduction • Transition to ocean form • Monogamy • Silvering of skin – deposition of purines • Polygamy • Polygyny (the most common polygamous mating such as guanine system in so far studied): One male • Parr territorial, smoltification results in has an exclusive relationship with two or more schooling females • Polyandry: One has an exclusive • Hormonal changes, increased NaK- relationship with two or more males ATPase in gills preparing for salt tolerance • : A member of one within the • Body shape changes becoming more social group mates with any member of the streamlined opposite sex.

spawning: • http://www.youtube.com/watch?v=RrMAOBT_Vco&NR=1 • Hermaphrodites • http://www.youtube.com/watch?v=NVqf2geKju4 – Sequential • • http://www.youtube.com/watch?v=v1SW-pl2gYs&feature=related – Simultaneous • http://www.youtube.com/watch?v=2TnB4dm3KyM&feature=related • Sea urchin fertilization • http://www.youtube.com/watch?v=T6BtSMerBmw&feature=related • Sea hare • http://www.youtube.com/watch?v=6lp87hrb-5I • Cuttlefish mating • http://www.youtube.com/watch?v=fR7Dqf0vzzQ&feature=related

• Protandry: Simultaneous hermaphrodite Where an is born • Hamlet as a male, and • Sea hares then changes sex • to a female - clownfishes

3 • Protogyny: Where the organism starts as a female, and then changes sex to a male - wrasses

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