Why the low fertility?

Transcription

Why the low fertility?
Why the low fertility?
Insights from Three Lines of
Social and Evolutionary Psychological Research
Social and Evolutionary Psychological Research
Norman Li, MBA, PhD
Lee Kuan Yew Fellow
Associate Professor of Psychology
Associate Professor of Psychology
School of Social Sciences
Singapore Management University
www.normli.com
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Singaporeans are
marrying later...
i l
Age at first marriage
30
29
28
27
26
Men
25
Women
24
23
22
1970
1980
1990
2000
2009
Data source: Singapore Department of Statistics
2
and are having less children...
and are having less children...
Fertility rate
2
1.9
1.8
1.7
1.6
15
1.5
1.4
1.3
1.2
Data source: Singapore Department of Statistics
3
Why?
• Undoubtedly, there are many factors involved, including economic and sociological ones
g
• Today, we will look at 3 relevant issues from social and evolutionary psychological perspectives
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1) Mate Selection Criteria
1) Mate Selection Criteria
• Mate preference studies across cultures and time:
– For long‐term mates, women not only place greater value on social g
yp
g
status and resources than men do (Buss, 1989; Buss & Barnes, 1986; Hill, 1945, McGinnis, 1958, Sprecher, Sullivan, & Hatfield, 1994)...
– but they also prioritize having a minimum level of social status in their mates (Li, Bailey, Kenrick, Linsenmeier, 2002; Li & Kenrick, 2006)
• Even though most women aren’t holding out for the most affluent men, they tend to require their long‐term mates to meet or exceed some minimum level of social status (or resources)
(
)
• How is that minimum level determined?
• This minimum level may be a woman's own social status or income level
5
Comparing women with
hi h
high vs. low incomes
l i
• Structural Powerlessness Hypothesis (Buss & Barnes, 1986; Eagly & Wood, 1999)) p
proposes:
p
– Women have traditionally been excluded from power and economic resources
– These are domains largely controlled by men
These are domains largely controlled by men
– So, women seek economic resources in their long‐term mates
• If this is true, then we should expect
– women who make high incomes to place less emphasis on a mate’s income
• However...
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Hypergamy
Most studies indicate the opposite: women (on average) who make higher incomes place even greater value on a potential g
p
g
p
mate’s income
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Hypergamy
Buss (1989)
• Compared to women with lower salaries, women who made higher salaries had higher education and had higher self‐esteem, and placed higher value on mates who
–
–
–
–
–
–
have professional degrees
have
professional degrees
have high social status
have greater intelligence
are tall
are independent
are self‐confident
are self
confident
• Women’s own income correlated positively with their ideal mate’s income and the desire for a mate with a professional degree
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Hypergamy
• Positive correlation between women’s expected post‐college earnings and importance ascribed to “good financial prospect” (Weiderman & Allgeier, 1992))
• Female medical school students expecting a high income want to marry p
g
g
y
men with equal or higher incomes and status (Townsend, 1989)
• Online ads: Women who offer financial resources or resource acquisition skills are more likely to request these qualities (Weiderman, 1993)
• An internet study (n=1,851) found that women with a high income prefer a mate with good financial prospects over one who is physically attractive (Moore et al 2006)
(Moore et al., 2006)
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Hypergamy
Cross‐cultural studies...
• In personal ads, Spanish women who have more status and resources were more likely to seek men with status and resources (Gil‐Burmann et al., 2002)
• Jordanian women and men with high SES place more value a mate with degrees and who is ambitious /industrious (Khallad, 2005)
• Serbian women’s status correlated positively with their concern for a potential mate’s SES (Todosijevic et al., 2003)
• Singaporean women place much higher value on “social level” than do American women (Li, Valentine, & Patel, 2011)
American women
(Li Valentine & Patel 2011)
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So...
• As women (on average) become more educated and earn more income, their requirements for a mate’s social status and earning power tend to increase, thereby decreasing the number of eligible men
number of eligible men
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Why?
• Mate selection criteria may be rooted in evolutionary history: – Although a higher male income may not be necessary for offspring survival in the modern world, our brains evolved in ancestral times when male provisioning may have been crucial
when male provisioning may have been crucial
– So, women may have evolved a preference for a long‐term mate who offers advantages in social status and/or resources (Buss & Schmitt, 1993 S
1993; Symons, 1979)
1979)
– Not easily overturned (e.g., women prefer men who are taller than themselves)
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Future directions
Future directions
• Not all women are set on significantly marrying up
• Investigate psychological factors that underlie mate I
ti t
h l i l f t th t d li
t
preferences of these women
• Can such factors be cultivated?
Can such factors be cultivated?
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2) Materialism
2) Materialism
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Singapore has been very
economically successful
i ll
f l
15
and people now have
more and more purchasing power
d
h
16
Consumerism
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2) Materialism
2) Materialism
• In modern economies, people value and strive for material possessions (Fromm, 1976; Leach, 1993)
• Materialism may compete with other values M t i li
t ith th
l
(Burroughs & Rindfleisch, 2002)
• People who are more materialistic and value financial goals
p
g
– place less value on:
• affiliative goals (Kasser & Ryan, 1993)
• relational warmth (Richins & Dawson, 1992)
• close relationships (Burroughs & Rindfleisch, 2002)
– have more conflicts with friends and romantic partners have more conflicts with friends and romantic partners (Kasser & (Kasser &
Ryan, 2001)
– have less satisfaction with family life (Nickerson et al., 2003)
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The incompatibility of materialism and children
d hild
Materialism‐
based happiness
-.20*
-.50*
Life Satisfaction
.20*
Attitude toward marriage
.36*
Desire for children
χ2 = 2.16, p = .34, CFI = 1.00, RMSEA = .01, LL = .00, UL = .02, SRM = .02
Source: Li, Valentine, & Patel (2011)
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So...
• In the modern world, there may be a built‐in tradeoff between economic prosperity and procreational success
between economic prosperity and procreational success
• A tempering of materialistic values may boost relational and family goals
family goals
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3) Life History Theory
3) Life History Theory
• Developed by evolutionary biologists to explain how organisms (including humans) adaptively allocate energy, time and resources across their lifetime toward different
time, and resources across their lifetime toward different activities (e.g., Charnov, 1993; Daan & Tinbergen, 1997; Low, 2000)
• Primary tradeoff: reproductive vs. somatic effort
– Reproductive effort: intrasexual competition for mates, courtship, copulation, gestation, birth, offspring care
– Somatic effort: maintaining and growing the body/mind; acquiring size, immunity, knowledge, skills; ultimately leading to enhanced
size, immunity, knowledge, skills; ultimately leading to enhanced future reproduction
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Slow versus Fast
Lif Hi
Life History Strategy
S
• Fast strategy: invest less in somatic development, reproduce as quickly as possible
• Slow strategy: invest more in somatic development, reproduce later
• Species that evolved in harsh and unpredictable environments tend to adopt fast LH strategies
• Species that evolved in harsh but predictable
( d th
(and thus, managable) environments tend to
bl )
i
t t dt
adopt slow LH strategies
slow l
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Source: Griskevicius et al. (in press)
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An individual's LH strategy
may also be variable
• A person’s LH strategy may be sensitive to environmental cues ((Daan & Tinbergen, 1997; Ellis et al., 2009)
g
),, including
g
– harshness of environment during childhood
– how safe and predictable the current environment is
• Harshness of environment ~ socioeconomic status (SES)
• If low‐SES childhood, then adopt a faster LH strategy
– reproduce faster
• If high‐SES childhood, then adopt a slower LT strategy
– invest more, reproduce later
• LH
LH strategies can be dormant in benign environments, but strategies can be dormant in benign environments but
may emerge under conditions of economic duress
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• Griskevicius, Delton, Robertson, & Tybur (2011)
– primed
primed people with mortality cues via a NY Times people with mortality cues via a NY Times “article”
article –
Dangerous Times Ahead: Life and Death in the 21st Century
• Article discussed recent increases in violence in the U.S., noting increases in shootings in both residential and commercial areas, and concluding that random
shootings in both residential and commercial areas, and concluding that random deaths are becoming a more common part of life
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In How Many Years
Do You Want to Have Your 1st Child?
Griskevicius, Delton, Robertson, & Tybur (2011)
In line with
SLOWER
95
9.5
Childhood SES
Strategy
YEAR
RS FRO
OM NOW
W
9.0
Poor
Middle
8.5
Wealthy
ea t y
8.0
75
7.5
7.0
In line with
FASTER
Strategy
6.5
Control
Mortality
ENVIRONMENT
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In How Many Years
Do You Want to Have Your 1st Child?
Griskevicius, Delton, Robertson, & Tybur (2011)
In line with
SLOWER
95
9.5
Strategy
YEAR
RS FRO
OM NOW
W
9.0
Shift to
t
FASTER
Shift to
SLOWER
Childhood SES
Strategy
Poor
Strategy
Middle
8.5
Wealthy
ea t y
8.0
75
7.5
7.0
In line with
FASTER
Strategy
6.5
Control
Mortality
ENVIRONMENT
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Further Your
Education/Career
Start Family
Sooner
S
OR
Griskevicius, Delton, Robertson, & Tybur (2011)
Further
Education
8.0
Childhood SES
/Career
SLOWER
Poor
7.0
Middle
Strategy
W lh
Wealthy
6.0
FASTER
Strategy
Start
Family
y
5.0
4.0
Sooner
Control
Mortality
ENVIRONMENT
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So...
• When people who grow up in safe, resource‐rich environments face danger (or uncertainty or stress) they
environments face danger (or uncertainty or stress), they may react by investing more time and energy in somatic development and delaying marriage and family
• Encouraging high‐SES people (those who grew up in high‐SES g g g
p p (
g
p
g
conditions) to reproduce earlier may require having these people feel safer, more secure, and less stressed.
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Summaries from
3 lines of research
• Mate selection research – education and career success may (on average) induce women to increase their requirements
(on average) induce women to increase their requirements for status and income in potential mates, thereby making it more difficult to find suitable mates
• Materialism – economic prosperity encourages materialism, p p y
g
,
which may compete with desires for marriage and family
• Life history theory – greater uncertainty or stress may lead individuals who grew up in stable, high‐SES conditions, to delay reproduction
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Conclusion
• Policymakers hoping to halt or reverse the trend of delayed marriage and decreased reproduction may benefit from a
marriage and decreased reproduction may benefit from a consideration of these factors, aided by an understanding of evolutionary social psychology
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