Bio 116

Front 1

Energetics and Economics of Sex

Back 1

~Reproductive behavior
~Parent-Parent conflict
~Parent-Offspring conflict
~Sibling competition
~In all these interactions there is usually a balance between the parties

Front 2

Reproductive behavior

Back 2

~Costs of finding a mate
~Costs of maintaining territories -- efforts involve various signaling devices such as song or calling, building nests, etc.
~Costs of conflict with other suitors in male-male competition to get access to females
~Being inattentive and vulnerable to predators during copulation

Front 3

Parent-Parent conflict -- Anisogamy

Back 3

When there is a large difference in gamete size (imagine a chicken egg and a chicken sperm). In these organisms there is a potential asymmetry between the energy investment in producing young.

Front 4

Parent-Parent conflict -- Isogamy

Back 4

When gametes are approximately the same size

Front 5

Parent-Offspring conflict

Back 5

~Young have energetic needs for growth and development and parents have to supply that energy, either behaviorally (bringing food), in the gamete (yolk), or through the placenta or equivalent
~It is in the interest of the young to demand nutrients and in the interest of the parent to limit that demand in order to be able to reproduce again
~This is especially a concern when one parent does all the care

Front 6

Sibling-Sibling competition

Back 6

~It is in the interest of each individual offspring to maximize its access to nutrients
~In some cases, offspring will kill siblings or the eggs of the mother
~In some cases, such as hyenas, a firstborn will kill some of the following siblings