Download Reproduction Types Asexual fission budding Parthenogenesis

Types
Reproduction
• Asexual
• Sexual
• Sexual vs. asexual – costs associated with
sexual but benefits (“lottery” model)
Asexual
fission
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Fission
budding,
parthenogenesis
Fragmentation- the body of the parent breaks
into distinct pieces, each of which can produce
an offspring. Planarians exhibit this type of
reproduction.
• Regeneration- a piece of a parent is detached, it
can grow and develop into a completely new
individual. Echinoderms exhibit this type of
reproduction.
budding
Parthenogenesis
• in females, where growth and
development of embryos occurs without
fertilization by a male (rotifers,
crustaceans, some sharks, nematodes)
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Sexual reproduction
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Broadcast spawning
Live birth
Mating systems
Hermaphrodites
– Sequential
– Simultaneous
fertilization
Broadcast spawning
• One of the
most
common
forms of
reproduction
in the oceans
• Eggs and
sperm are
released into
the water
column and
are fertilized
by neighbors
• Often it is
synchronous
Live birth in fishes
Anadromous fishes
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smoltification
Mating systems in sexual
reproduction
• Transition to ocean form
• Silvering of skin – deposition of purines
such as guanine
• Parr territorial, smoltification results in
schooling behavior
• Hormonal changes, increased NaKATPase in gills preparing for salt tolerance
• Body shape changes becoming more
streamlined
• Monogamy
• Polygamy
• Polygyny (the most common polygamous mating
system in vertebrates so far studied): One male
has an exclusive relationship with two or more
females
• Polyandry: One female has an exclusive
relationship with two or more males
• Promiscuity: A member of one sex within the
social group mates with any member of the
opposite sex.
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• Hermaphrodites
Coral spawning:
http://www.youtube.com/watch?v=RrMAOBT_Vco&NR=1
http://www.youtube.com/watch?v=NVqf2geKju4
Barnacle
http://www.youtube.com/watch?v=v1SW-pl2gYs&feature=related
http://www.youtube.com/watch?v=2TnB4dm3KyM&feature=related
Sea urchin fertilization
http://www.youtube.com/watch?v=T6BtSMerBmw&feature=related
Sea hare hermaphrodite
http://www.youtube.com/watch?v=6lp87hrb-5I
Cuttlefish mating
http://www.youtube.com/watch?v=fR7Dqf0vzzQ&feature=related
Simultaneous hermaphrodite
• Hamlet fish
• Sea hares
• Barnacles
– Sequential
– Simultaneous
• Protandry:
Where an
organism is born
as a male, and
then changes sex
to a female clownfishes
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• Protogyny: Where the organism starts as a
female, and then changes sex to a male wrasses
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