Mating systems

1
Mating systems

• Three basic mating system flavors
• Monogamy (one permanent mate)
• Polygamy (many wives)
• Polyandry (many husbands)
• These basic flavors should be considered extremes
  of a continuum
• Species/individuals may exhibit a propensity to
  gravitate to one or more of these strategies
  based on the ecological and genetic constraints
  they experience

2
Monogamy in insects?

• Single male-female pairs of burying beetles will
• Find a dead animal
• Bury it
• Oviposit
• However males will call other females if the
  carcass can support more offspring
• Is this monogamy or conditional monogamy (i.e.
  polygamy)?

Nicrophorus americanus
3

• Monogamy in mammals should occur under some
  conditions
• Females typically come equipped for child care
• Paternal assistance really can only enhance
  female effort

4

• Adaptive value of monogamy
• Mate guarding and paternal certainty
• Enhanced paternal care

Djungarian (Russian Dwarf) hamsters Clearly a
monogamous mammal.

• Males assist in birth and care of offspring
• Are also key in the control of female body and
  nest burrow temperature
• Paternal care correlates to higher survival,
  birth and weaning weight

5
Monogamy in Primates? Correlation between females
that carry young and year round male
presence/association
6
Monogamy in birds Paternal assistance does
influence parental success
Snow bunting
7
How to define polygamy and polyandry
8

• Human polygyny (many women)
• The majority of human societies have probably
  permitted polygyny
• ancient Hebrew society,
• classical China,
• in Islam.
• many traditional African and Polynesian cultures.
  
• In India, polygyny was practiced from ancient
  times onward, though historically only kings were
  polygynous in practise.
• However, it was not accepted in
• ancient Greece or Rome,
• mainstream Christianity
• Mormonism was a notable exception