Chapter 10 class (exam4) Flashcards
Problem of classifying mating systems
if stallion keeps other males away from females - monogamous for female, but polygamy for male.
Mating system Categorization Criteria
- Number…
- Whether…
- Length…
- Number of partners individuals copulated with in a breeding season.
- Whether the sexes form pair bonds and cooperate in parental care
- Length of the pair bond
Major mating systems: A) M\_\_\_ B) Polyg\_\_ C) Polya\_\_\_ D) Polyg\_\_\_\_\_\_ E) Prom\_\_ F) Poly\_\_\_
A) Monogamy: one partner per season for one or both sexes
B) Polygyny: More than one partner per season for males
C) Polyandry: more than one partner per season for females
D) Polygynandry: multiple nonrandom mating by both sexes, with pair bonds and females preferring high ranking males
E) Promiscuity: multiple random mating by both sexes, no pair bonds
F) Polygamy: Individuals of either sex having more than one partner, thus covering polygyny, polyandry, polygynandry, and promiscuity
Monogamy
one partner per season for one or both sexes
Polygyny
more than one partner per season for males
Polyandry
more than one partner per season for females
Polygynandry
multiple nonrandom mating by both sexes, with pair bonds and females preferring high ranking males
Promiscuity
multiple random mating by both sexes, no pair bonds
Polygamy
Individuals of either sex having more than one partner, thus covering polygyny, polyandry, polygynandry, and promiscuity
Book’s Diagram
Female partners / Male partners
Monogamous species have fewer… (A)
Monogamy leads to… (B)
A) have fewer diseases. and fewer white blood cells.
B) Monogamy leads to parental care.
-avoid predators.
Mammalian Monogamy
- likelihood
- rare. less than 10% of mammals have male parental care, many of these are monogamous. Females may drive off other females, or in some social species suppress breeding in subordinate females.
Bird Monogamy
A) over 90%…
B) S__ female breeding makes …
A) Over 90% of bird species are monogamous, reflecting the greater value of male parental care in birds.
B) Synchronous female breeding makes it unprofitable for males to seek other mates
Male Extra-Pair Copulations (EPC’s)
A) beneficial if…
B) Songbirds often have…
C) EPC’s produced…
A) beneficial if offspring result, costly if mate copulates in his absence.
B) Songbirds often have 20-50% of babies sired by EPC’s.
C) EPC’s produced 10% or more babies in 15 of 32 species studied, and 70% of 150 species studied have EPC’s.
Mate guarding (males guarding females)
A) What is this?
B) Is it advantageous?
C) Why does it occur?
A) Males or females have one mate per breeding season.
B) This is rarely advantageous for males, so species-wide monogamy is rare.
C) A factor in its occurrence is few available females.
Mate assistance: When does it occur?
Occurs when males profit from investing in offspring and the female needs his help
Female-enforced
- define
- example
Females interfere with males seeking more mates
ex: beetles - male releases a hormone to attract females. He gets one. If he releases this hormone again, she attacks him.
Polyandry w/ Sex Role Reversal A) reverses... B) male care of young polyandry - the benefits of male guarding rise as: 1) 2) 3)
this is common in ___ ___ especially
A) reverses normal sex roles in parental care
B) male care of young polyandry - the benefits of male guarding rise as:
1) predation increases
2) # of available females decrease
3) differential effectiveness of male v. female nest protection increases (males better at protecting)
this is common in aquatic creatures especially.
[Resource Defense Polyandry] A) Sandpipers have... B) more \_\_ than \_\_ C) Nests in areas with ... D) \_\_\_ young
A) Clutches of eggs (4) at a time and can only expand reproduction by adding more clutches.
B) more males than females
C) big mayfly hatches - no problems feeding young
D) precocial young (can take care of themselves after hatching)
Precocial young
can take care of themselves after hatching
Lek Polyandry
A) __ defense
B) females are competing…
A) male defense
B) for males
[Genetic (indirect) benefits and polyandry] A) Good Genes Hypothesis B) Compatible Genes Hypothesis C) Genetic diversity hypothesis D) inbreeding avoidance hypothesis E) Fertilization Insurance Hypothesis
A) females seek EPC’s with superior males. Offspring survive better & reproduce better.
B) Extra Pair Copulation (EPC) sperm may be more compatible with female genes, more variable offspring result
C) EPC’s provide greater chance heterozygosity in offspring genes, producing fewer negative homozygous genes and better immune systems
D) if non-related males are unavailable and inbreeding occurs, females are more likely to engage in EPC’s.
E) EPCs mean a greater chance of viable sperm to fertilize eggs
[Genetic (indirect) benefits and polyandry]
Good Genes Hypothesis
females seek EPC’s with superior males. Offspring survive better & reproduce better.
[Genetic (indirect) benefits and polyandry]
Compatible Genes Hypothesis
Extra Pair Copulation (EPC) sperm may be more compatible with female genes, more variable offspring result
[Genetic (indirect) benefits and polyandry]
Genetic diversity hypothesis
EPC’s provide greater chance heterozygosity in offspring genes, producing fewer negative homozygous genes and better immune systems
[Genetic (indirect) benefits and polyandry]
Fertilization Insurance Hypothesis
EPCs mean a greater chance of viable sperm to fertilize eggs
[Female EPCs] Direct Benefits of Polyandry: A) Additional Resources Hypothesis B) Additional Care Hypothesis C) Infanticide Reduction Hypothesis
A) Female access to resources of EPC males
B) Neighboring males may help defend nests of females they mated with
C) Confusion about offspring paternity may decrease killing by other males
[Female EPCs Direct Benefits of Polyandry]
Additional Resources Hypothesis
Female access to resources of EPC males
[Female EPCs Direct Benefits of Polyandry]
Additional Care Hypothesis
Neighboring males may help defend nests of females they mated with
[Female EPCs Direct Benefits of Polyandry]
Infanticide Reduction Hypothesis
Confusion about offspring paternity may decrease killing by other males
Other Costs
include exposure to disease and parasites from other males
Polyandry w/o sex role reversal
in Cooperative (True) polyandry males..
share females and take their chances and fertilizing the egg
Polyandry w/o sex role reversal
in Sperm Replenishment Polyandry the female…
produces several individual or clutches of eggs per season needing fertilization each time
Polyandry w/o sex role reversal
in Prostitution Polyandry females …
mate with more than one male for access to resources or gifts given to mates.
[Polygyny - in the case when males can monopolize females]
Female Defense Polygyny
Females live in groups and males defend the group, provide little care and sire most offspring.
ex: lions, gorillas, etc.
[Polygyny - in the case when males can monopolize females]
Resource Defense Polygyny
Females NOT living in groups concentrate at food, nest sites, or other resources males can control.
[Polygyny - in the case when males can monopolize females]
Polygyny Threshold Model
identifies factors involved in choice of monogamy is polygyny. territorial resources seems the most important variable
[Polygyny - in the case when males CAN’T monopolize females]
Lek Polygyny
A) what happens?
Typical Ecological conditions:
1)
2)
A) Males gather at display areas
Ecological Conditions:
1) Male parental investment is NOT needed
2) male can’t control harem or territory
Hypothesis why males gather in leks:
A) _ _ hypothesis
B) _ _ hypothesis
C) _ _ hypothesis
A) hot spot hypothesis (males gather at intersections of female travel routes)
B) hot shot hypothesis (attractive males attract satellites that may intercept females)
C) female preference hypothesis (females prefer large groups of males)
Hot spot hypothesis
[hypothesis why males gather in leks]
males gather at intersections of female travel routes
some species support this hypothesis
hot shot hypothesis
[hypothesis why males gather in leks]
attractive males attract satellites that may intercept females
some species support this hypothesis
female preference hypothesis
[hypothesis why males gather in leks]
females prefer large groups of males.
attractive males removed from Great Snipe leks: other males move.
not a great hypothesis
Scramble Competition Polygyny
Scattered females, male must find and mate with as many as he can
i.e. fireflies
breeding season usually short
Explosive Breeding Assemblages
Clustered females, often too many males to defend female or territory
ex: horseshoe crabs. females attracted to beaches. when female shows up, males attach to back of shell. she crawls up and deposits eggs and leaves, he fertilizes them.
[Multiple mating by both sexes] In Dunnocks, when do the following happen? A) Monogamy B) Polyandry C) Polygyny D) Polygynandry
E) this all supports the idea that…
A) in rich areas males can defend one female
B) with less feed females range farther. Satellite males can sneak copulations and even help with the nest
C) rare males can defend the adjacent territories of 2 females
D) adjacent monogamous pairs merge territories and partners
E) …female ecology sets the rules for male competition and shapes mating systems
promiscuity
both sexes have multiple mating
[Characteristics Indicative of Mating Systems] Monogamy: 1) Body Size 2) Maturation 3) Reproductive Variance
1) Equal
2) Equal maturation time
3) Equal reproductive variability
[Characteristics Indicative of Mating Systems] Polyandry: 1) Body Size 2) Maturation 3) Reproductive Variance
1) Female Larger (because she’s producing eggs for multiple males)
2) Female slower to mature
3) Female greater reproductive variability
[Characteristics Indicative of Mating Systems] Polygyny: 1) Body Size 2) Maturation 3) Reproductive Variance
1) Male larger
2) Male slower to mature
3) Male greater reproductive variability
[Types of Polygyny]
Resource Defense:
A) Characteristics
B) Ecological Conditions
A) resources defended against other males
B) resources clumped
[Types of Polygyny]
Female Defense
A) Characteristics
B) Ecological Conditions
A) Females defended against other males
B) resources evenly spread
[Types of Polygyny]
Lek:
A) Characteristics
B) Ecological Conditions
A) males group up, females choose.
B) females widely distributed
[Types of Polygyny]
Scramble Competition
A) Characteristics
B) Ecological Conditions
A) males scramble for mates
B) many females briefly available
