Mating Systems and Parental Care Flashcards
Factors that predict parental care
Mating systems, Ecological factors, Physiological constraints, Territory size
Monogamy
Male and female pair bond
Short bonds, such as pair over a breeding season
Long term bonds pair for life
Males and females provide parental care
Polygyny
Males mate with multiple females
Can be simultaneous or succession
Common in mammals
Most advantageous to male reproductive success
Polyandry
Opposite of polygyny, females mate with multiple males
Can be simultaneous or succession
Males provide parental care
Rare (occur in inverts, amphibians, primates)
Simultaneous
Seen in polygyny and polyandry
mate with several females or males within a short period of time
Successive
Seen in polygyny and polyandry
mate with several females or males within longer duration of time
Promiscuity
Male and females both have multiple mating partners
Either male or female provides parental care
Seen in primates, some species of fish
Paternity certainty
External fertilization – male more sure he is father, male parental care
Internal fertilization – male not as sure he is father, female parental care
Seasonal harem
males only defend females during specific times of the year
Permanent Harem
males defend females throughout the year; more exhausting/energy used
Super harem
Male defends group of females in one area and males defend female group in another area
may occupy same location, engage in competition to decide which male is better and becomes leader
Leks
- group of males meet in specific areas to find mates together
- success rate small for males
- seen in birds, amphibians
Hotshot hypothesis
association with better looking males to appear more attractive to others
Describe the significance of the Sparrow Experiment
-Experiment: raising young
- Seaside Sparrow removed male, success at 98%
- Song Sparrow removed female, success at 69%
- Monogamous in current studies show greater reproductive success, preferred over polygany tactics
What can effect/alter maternal behaviors?
steroid hormones!
Name steroid hormones that can alter/effect maternal behaviors
Oxytocin (posterior pituitary), Vasopressin (posterior pituitary), Prolactin (anterior pituitary), Others like neurotransmitters (like dopamine and serotonin)
Name steroid hormones that can effect/alter paternal behaviors
Prolactin, Progesterone, Oxytocin, Vasopressin, Testosterone
Name costs of parental behavior
Risk of predation: vulnerable with young attached at the hip, care makes vulnerable
Huge investment of resources and energy
Lost opportunities: sacrificing one thing for another
Describe the Female rat in Kyphosis experiment: if given pups when not theirs, what behaviors will happen?
- the experiment began with ovaries removed from rats and drug to block prolactin
- rats treated with estradiol and progesterone (present during pregnancy)
- then different amounts of prolactin were dispersed: none (control), 10microg. or 50microg.
- conclusion: maternal behavior higher in female rats injected with prolactin compared to control
Infanticide
- See in polygyny
- Male kills off offspring
- Reasons: Inducing reproductive status (young care does not allow ovulation, will go into heat if no offspring); Frees up genetic competition; more resources (does not want to provide for others’ offspring)
Describe parental behavior cost in Common Eider
Have to sit on eggs, do not move to prevent eggs from freezing, huge weight loss creates own risk
Brood reduction
Occurs when female faces drain of resources and energy
Not all offspring will survive, engage in behavior to get rid of some offspring
Abandoned animal increase chance of their own survival
Siblicide
Offspring take each other out, stronger kick out weaker to promote survivability
Brood parasitism
No care at all for offspring (damn, that’s tough)
