Reproductive Strategies for Survival

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Reproductive Strategies for Survival
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Sex at Sea

• Broadcast spawning is when reef fish gather and
  simultaneously release their eggs and sperm into
  the water where fertilisation occurs

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Sex at Sea

• Broadcast spawning is when reef fish gather and
  simultaneously release their eggs and sperm into
  the water where fertilisation occurs
• This occurs where there are strong currents which
  allows the fertilised eggs to be carried away
  from the reef and the predators that live in the
  habitat.

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Sex at Sea

• Some examples of broadcast spawners include
• Butterfly fish
• Coral trout

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of eggs.

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of
  eggs.
• Any fertilised eggs are left on their own.

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of
  eggs.
• Any fertilised eggs are left on their own.
• Embryonic development takes place within the
  membranes that enclose the egg.

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of
  eggs.
• Any fertilised eggs are left on their own.
• Embryonic development takes place within the
  membranes that enclose the egg.
• The egg yolk provides nutrients

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of
  eggs.
• Any fertilised eggs are left on their own.
• Embryonic development takes place within the
  membranes that enclose the egg.
• The egg yolk provides nutrients
• After several days the newly hatched eggs break
  from the membranes.

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of
  eggs.
• Any fertilised eggs are left on their own.
• Embryonic development takes place within the
  membranes that enclose the egg.
• The egg yolk provides nutrients
• After several days the newly hatched eggs break
  from the membranes.
• The larva are small and float in the see making
  up zooplankton.

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Sex at Sea

• Broadcast spawners put all their energy into egg
  production and produce very large numbers of
  eggs.
• Any fertilised eggs are left on their own.
• Embryonic development takes place within the
  membranes that enclose the egg.
• The egg yolk provides nutrients
• After several days the newly hatched eggs break
  from the membranes.
• The larva are small and float in the see making
  up zooplankton.
• When the yolk supply is used up, the larva must
  find their own food and eventually become
  juvenile fish and later a sexually mature adult
  fish, which can take many years

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Sex at Sea
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Demersal Spawning

• Demersal eggs do not float and a female fish that
  produces such eggs may lay them in a nest in the
  sand, or attach them to some part of the reef
  surface.

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Demersal Spawning

• Demersal eggs do not float and a female fish that
  produces such eggs may lay them in a nest in the
  sand, or attach them to some part of the reef
  surface.
• After being laid, the eggs are fertilised.

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Demersal Spawning

• Demersal eggs do not float and a female fish that
  produces such eggs may lay them in a nest in the
  sand, or attach them to some part of the reef
  surface.
• After being laid, the eggs are fertilised.
• Unlike broadcast spawning, demersal spawner give
  some care to their eggs by guarding them until
  they hatch
• E.G the anemone clownfish.

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Demersal Spawning

• Demersal eggs do not float and a female fish that
  produces such eggs may lay them in a nest in the
  sand, or attach them to some part of the reef
  surface.
• After being laid, the eggs are fertilised.
• Unlike broadcast spawning, demersal spawner give
  some care to their eggs by guarding them until
  they hatch
• E.G the anemone clownfish.

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Demersal Spawning

• Because demersal spawners invest energy into
  guarding their eggs, they produce fewer are
  larger eggs than broadcast spawners

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Sex at Sea

• Living organisms have evolved many different
  reproductive strategies, which must be suitable
  for the environmental conditions in the habitats
  where the species live.

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Reproductive Strategies

• Type of reproduction
• Asexual
• Sexual

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Reproductive Strategies

• Type of reproduction
• Asexual
• Sexual
• Gender system
• Separate males and females
• Hermaphrodite
• Parthenogenesis (fertilisation occurs without a
  male)

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Reproductive Strategies

• Type of reproduction
• Asexual
• Sexual
• Gender system
• Separate males and females
• Hermaphrodite
• Parthenogenesis (fertilisation occurs without a
  male)
• Mode of fertilisation
• External
• internal

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Reproductive Strategies Mating Systems

• Monogamy is when one male only mates with one
  female for one or more breeding seasons or for
  life.

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Reproductive Strategies Mating Systems

• Monogamy is when one male only mates with one
  female for one or more breeding seasons or for
  life.
• Most bird species (about 90) are monogamous e.g.
  emperor penguins and eagles

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Reproductive Strategies Mating Systems

• Monogamy is when one male only mates with one
  female for one or more breeding seasons or for
  life.
• Most bird species (about 90) are monogamous e.g.
  emperor penguins and eagles
• Monogamous parenting requires the care of both
  parents for tasks
• Defending a nesting site
• Incubating eggs
• Feeding offspring

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Reproductive Strategies Mating Systems

• Monogamy is when one male only mates with one
  female for one or more breeding seasons or for
  life.
• Most bird species (about 90) are monogamous e.g.
  emperor penguins and eagles
• Monogamous parenting requires the care of both
  parents for tasks
• Defending a nesting site
• Incubating eggs
• Feeding offspring
• The young of many, are born featherless, blind
  and helpless.

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Reproductive Strategies Mating Systems
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Reproductive Strategies Mating Systems

• Polygamy is when one male or one female has
  multiple partners during breeding season.

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The End