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Question 1

Why Alternative Mating Stratagies?

Answer 1

• Evolutionary goal = maximize individual fitness
• Leads to conflict (ex: battle of the sexes) and alternate mating stratagies
• Some individuals use different methods to reproduce successfully

Question 2

External Fertilization

Answer 2

Fertilization occurs outside the body, requires water \, Gamates released in large numbers by both sexes

Question 3

Internal Fertilization

Answer 3

Occurs inside a female; males still release lots of sperm; females produce fewer eggs, adaption to terrestrial life.

Question 4

Synchronization in External Fertilization

Answer 4

Requires: Environmental cures (ex: temperature, moon cycle).
Pheromones, close proximity, mating rituals.

Question 5

Examples of Synchronization

Answer 5

• Coral Spawning: Salinity, temperature, daylength, full moon.
• Tilapia: Dominant males use pheromone-rich urine.
• Frogs (Amplexus): Physical contact ensures timing
• Mandarin Fish: Courtship dance to synchronize

Question 6

Satellite (Sneaky) Males

Answer 6

• Smaller males avoid direct competition
• Sneak in to fertilize eggs during or after dominant male mates.
• Seen in both external and internal fertilizing species.

Question 7

Sockeye Salmon

Answer 7

• Hooknose: Large males, defend territory, attract females
• Jack: Return earlier, smaller, sneak in during spawning.
• Jack avoid ocean risks bust still reproduce
• Both strategies coexist = Equal average fitness.

Question 8

Spounge Louse (Paracerceis sculpta)

Answer 8

• Internal fertilization crustacean
• 3 male morphs:
  a (alpha) - Largest, defends harems.
  B (Beta) - Mid-sized, looks like female, sneaks in.
  V (gamma) - Smallest, looks like juvenile, sneaks in.
• Each strategy offers reproductive success.

Question 9

Dung Beetles (Onthophagus spp.)

Answer 9

• Large, Horned males: Guard egg chamber and provide food.
• small, unhorned males: Sneak in to mate.
• Male morphs determined by nutrition during development.

Question 10

Ruffs (Birds - Lekking Species)

Answer 10

• Independents (84%): Dark, territorial.
• Satellites (14%): White, tolerated by independents, increase mate attraction.
• Faeders (1%): Female mimics, sneak matings.
• All strategies present due to fitness balance.

Question 11

Andromorphs in Blue-tailed Damselflies

Answer 11

• Males grab females for long copulations
• Some females mimic males (“andromorphs”) to avoid harassment.
• Andromorphs mate less often but benefit by reducing risk and energy loss

Question 12

Fitness of Stratagies

Answer 12

• Strategies persist if average fitness is equal over time
• Example: Side-blotched Lizards have 3 strategies:
• Each beat one and loses to another (like rock-paper-scissors).
• year-to-year fitness varies but balances out.