HOW DID THE KRUMMHORN ELITE MALES ACHIEVE ABOVE-AVERAGE REPRODUCTIVE SUCCESS? H e i k e K l i n d w o r t h and Eckart Voland Universitf~'t G~ttingen
The wealthy elite males of nineteenth-century K r u m m h 6 r n (Ostfriesland, Germany) achieved an above-average reproductive success. M e m b e r s h i p in the elite class was determined from a list of the 300 richest m e n in the Ostfriesland district compiled by authorities in 1812. The m a i n c o m p o n e n t s establishing the l i n k between cultural success and reproductive success are 1.
2.
3.
differences in the n u m b e r of o f f s p r i n g o w i n g to differences b o t h in time s p e n t in fecund marriage (mating success) a n d in rate of reproduction; differences in the p r o b a b i l i t i e s of one's a d u l t o f f s p r i n g m a r r y i n g locally vs. e m i g r a t i n g u n m a r r i e d o w i n g to differential a b i l i t y to allocate resources that e n h a n c e the "social p l a c e m e n t " of a d u l t offspring; a n d differences in the p r o b a b i l i t y of total r e p r o d u c t i v e failure (lineage extinction).
Contrary to w h a t m i g h t be expected, infant s u r v i v o r s h i p was l o w e s t a m o n g s t the richest families. We conclude that to a great extent f e m a l e s ' reproductive decisions contribute to the greater r e p r o d u c t i v e success of the elite males. KEY WORDS: Reproductive strategies; C u l t u r a l / r e p r o d u c t i v e success; Differential male m a t i n g success; F e m a l e r e p r o d u c t i v e decisions; Lineage extinction; E v o l u t i o n a r y d e m o g r a p h y ; K r u m m h 6 r n (Germany). Received January 23, 1995; accepted March 10, 1995. Address all correspondence to Eckart Voland, Zentrum fiir Philosophie und Grundlagen der Wissenschaft, Universitdt Giessen, Otto-Behaghel-Strasse 10 C/II, D-35394 Giessen, Germany. Copyright 9 1995 by Walter de Gruyter, Inc. New York Human Nature, Vol. 6, No. 3, pp. 221-240. 221
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Ever since Irons (1979) published his data on the positive correlation of personal wealth with individual reproductive success among Yomut Turkmen, major research efforts have been undertaken to verify or to dismiss the widely disputed assumption of the general applicability of his principal result to other societies. Some 15 years of research now suggest that in many historical and contemporary non-industrial populations, the cultural success/reproductive success link actually has an evolutionary explanation (for reviews, see Betzig 1986; Cronk 1991; Irons 1993; Low 1993; P6russe 1993). Whether or not this correlation persists in industrial societies is a matter of some doubt (P6russe 1993; Vining 1986). Factors that are known to establish fitness differentials among men in traditional and historical populations include 9 differential mating success (with respect to the number of wives in polygynous populations (e.g., Borgerhoff Mulder 1987); wives' reproductive value [age] in monogamous populations (e.g., Roskaft et al. 1992); extramarital matings (e.g., Flinn 1986); and remarriage (e.g., Boone 1986), 9 differential marital fertility (e.g., Irons 1979), 9 differential infant and child survivorship (e.g., Hughes 1986), and finally 9 differential allocation of marriage and reproductive chances ("social placement") of one's adult offspring presumably by means of inheritance and dowry payments (e.g., Roskaft et al. 1992). Although previous historical demographic analyses of the eighteenth- and nineteenth-century Krummh6rn population (Ostfriesland, Germany) revealed that here too cultural success (as measured by landownership) correlated positively with reproductive success (Voland 1990; Voland and Engel 1990), neither the relative significance of the single fitness components nor the actual causes of the correlation are well understood. With this study we aim to uncover the reproductive strategy adopted by the 1812 Krummh6rn elite men that eventually enabled them to achieve an increased reproductive success. We analyze their life- and reproductive histories and compare them with those of the non-elite male population to determine the specific demographic components (i.e., fertility, infant survivorship, or social placement of surviving offspring) that systematically contribute to fitness differentials within the population. With this, we aim at three insights:
Krummhi~rn Above-Average Reproductive Success
223
1. A reconstruction of the K r u m m h 6 r n social structure based on a historical source that provides the n a m e s of the 300 richest m e n in the Ostfriesland district allows us to check the validity of our p r e v i o u s social classification scheme, which was created on a c o m p a r a t i v e basis only. 2. A comprehensive u n d e r s t a n d i n g of the c o m p o n e n t s of differential reproduction enables us to d e t e r m i n e which evolved mechanisms have to be taken into account in comparisons of h u m a n reproductive performance. 3. Both of the previous insights can help us to u n d e r s t a n d w h o or w h a t caused the increased r e p r o d u c t i v e success of the male elite.
MATERIAL A N D METHODS The Krummh6rn Families This investigation is based on a family reconstitution in the eighteenth- and nineteenth-century K r u m m h 6 r n population. The K r u m m h6rn region is situated in the n o r t h w e s t of Ostfriesland ( G e r m a n y ) and comprises an area of 153 k m 2 (Figure 1) and a nearly stable cross-sectional
Figure 1. The location of the Krummh6rn.
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population size of approximately 14,000 individuals during the eighteenth and nineteenth centuries. Its soil ("younger marsh") is extremely fertile and allows for a highly productive agricultural and dairy farming system. Large and medium-sized businesses dominated the farming economy during the eighteenth and nineteenth centuries. A capital- and market-oriented agricultural system was able to develop early in this area and replaced a pure subsistence economy earlier than elsewhere in Germany. Accumulation of proceeds led to remarkable concentrations of wealth in some lineages. As a normative rule, but by no means automatically, the youngest son inherited the farm from his father (ultimogeniture). The heir had to pay compensation to his siblings, with each sister receiving only half of what each brother could expect. Because of its geographic situation (surrounded by the North Sea and by inaccessible moorlands), the population was unable to expand either its geographical area or its population size. The very early and complete colonization of the area prevented any significant population increase, since absolutely no commons or wasteland was available. It was access to land that determined the social structure of this population. If a farmer possessed at least 25 "Grasen" of land on his o w n (1 "Gras" = approx. 0.37 ha), or if he had at least 50 "Grasen" on lease, he was entitled to vote and to hold political and church offices. Thus, access to land defined social prestige, political influence and rights, and, of course, the everyday transactions of the people. The social class contrast between farmers and laborers was extremely marked in nearly every material and nonmaterial aspect of lifestyle. Thinking, feeling, and behaving according to social differences were underlined by the prevailing Calvinist religion, which tended to promote attitudes of social inequality. Social historians describe the rural Krummh6rn society as a "farmers' aristocracy" (Swart 1910: Bauernaristokratie). The extreme gap between farmers' and laborers' opportunities was noted by everybody and finally led to social dissatisfaction on the part of the working class during the course of the nineteenth century (Engel 1990 provides more details and further references). The entries from church registers in 13 of a total of 32 Krummh6rn parishes (Figure 2) were assigned to family lineages according to the standards of historical demography (e.g., Henry and Blum 1988). In comparison with other European regions, church registration started relatively late in this area, often not until the end of the seventeenth or even the beginning of the eighteenth century. By and large, registration is complete and sufficiently reliable from 1720 onwards. The likely gaps in the registration of stillbirths prior to 1750 do not affect the present study. The data were organized with the KLEIO databank system and analyzed by SPSS-x routines.
Krummhorn Above-Average Reproductive Success
225
KRUMMHORN
)persum
N
~den 012
Km
Figure 2. The parishes of the Krummhbrn (filled circles denote parishes in the "Krummh6rn data base"). The Samples In 1812, when Ostfriesland was under Napoleon's rule, the French authorities compiled a list of the 300 absolutely wealthiest men (as revealed by tax payments) to determine which persons were eligible to be members of the regional parliament. Because this list also contains places of residence, we are able to identify the 83 men who lived in the Krummh6rn area of Ostfriesland. We regard this sample as the 1812 Krummh6rn wealthy male elite. The data from parishes in which 43 of these 83 men lived had already been entered into the data base. In order to maximize sample size, a selective search was made in the remaining church registers for entries of vital and reproductive events relating to the other 40 men. Although we were eventually able to trace the life histories of 80 of the 83 men listed (96.4%), two of them died unmarried and thus were excluded from further analysis. Hence, the elite sample comprises 78 married men (see Appendix for names and places of residence). We contrast the reproductive data of the elite men with those from the male married population at large (non-elite sample). As all of the 78
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elite m e n contracted their first marriage b e t w e e n 1760 and 1810, w e accordingly limited the p o p u l a t i o n s a m p l e to those m e n w h o m a r r i e d for the first time d u r i n g the same time span. This selection led to a sample size of 954 non-elite m e n w h o s e r e p r o d u c t i v e histories can be regarded as completely k n o w n (see below). The ratio of 954 non-elite m e n to 22 elite m e n with c o m p l e t e l y k n o w n reproductive histories in the K r u m m h 6 r n data base indicates that the elite sample represents 2.25% of the total p o p u l a t i o n of m a r r i e d men. A r e p r o d u c t i v e history is considered to be c o m p l e t e l y k n o w n only if both the beginnings and the ends of all of a person's marriages are docu m e n t e d in the church records. The b e g i n n i n g of a marriage is indicated b y an entry for either the w e d d i n g or the banns. The end of a m a r r i a g e is defined b y the death of one or both spouses (providing it was k n o w n that the deceased's spouse had definitely not d i e d earlier). U n d e r these rather restrictive conditions, migration is unlikely to be a c o n f o u n d i n g factor and thus all births and deaths occurring in these families are k n o w n with near certainty. According to these criteria, the r e p r o d u c t i v e histories of 60 elite and 954 non-elite m e n can be r e g a r d e d as c o m p l e t e l y k n o w n . O w i n g to long-range mobility on the part of s o m e of the population, however, the reproductive histories of 18 elite m e n r e m a i n incomplete. Moreover, a marriage is considered to be biologically complete if it lasted at least until the wife's forty-fifth birthday. This category of reproductive history additionally requires the wife's exact birthdate to be k n o w n , and as usual in historical d e m o g r a p h y only first marriages of b o t h spouses are considered in that case. The influence of mortality on such fertility measures as age at last birth or m e a n length of birth intervals is thus excluded.
RESULTS: C O M P O N E N T S OF DIFFERENTIAL REPRODUCTIVE SUCCESS
Fertility and Its Determinants
Number of offspring. On average, m a r r i e d elite m e n had a m e a n of 6.58 (_+ 2.84, n = 60) children (including stillbirths), w h i c h is significantly m o r e than the non-elite m e a n (x = 4.59, + 2.85, n = 954, t = 13.40, df = 1012, p < .001). Two factors that contribute to the greater n u m b e r of offspring a m o n g elite m e n can be determined: the n u m b e r of years spent in f e c u n d marriage and the rate of reproduction.
KrummhOrn Above-Average Reproductive Success
227
Years spent in fecund marriage. C o m p u t i n g the n u m b e r of y e a r s s p e n t in fecund m a r r i a g e b y a d d i n g all of the y e a r s d u r i n g w h i c h a m a n w a s m a r r i e d to a w o m a n u n d e r the a g e of 45 yields an interesting outcome: elite m e n are able to m o n o p o l i z e 21.43 (+ 6.35, n = 60) y e a r s of f e m a l e fecundity, w h e r e a s non-elite m e n e n d e d u p w i t h only 17.33 y e a r s on average (_+ 7.94, n = 923, t = 4.77, df = 72, p < .001). A l t h o u g h c o m p a r i s o n of the contribution of second a n d third m a r r i a g e s to total y e a r s s p e n t in f e c u n d m a r r i a g e did not reveal any significant differences b e t w e e n the s a m p l e s (Table 1, X2 = .329, df = 1, ns), the h i g h e r m a t i n g success of elite m e n is c o m p l e t e l y d u e to their first w i v e s ' y o u n g e r ages. Elite m e n ' s brides h a d a m e a n age of 22.44 years (_+ 3.31, n = 64) a n d thus w e r e significantly y o u n g e r t h a n the p o p u l a t i o n m e a n (~ = 26.70, _+5.29, n = 962, t = 9.52, df = 86.8, p < .001). These figures agree w i t h the results r e p o r t e d b y Voland a n d Engel (1990). Women's age at last birth. The w i v e s of the elite males started h a v i n g children sooner, but they s t o p p e d sooner as well. Their m e a n age at last birth w a s 37.47 (_+ 4.41, n = 42), whereas the w i v e s of non-elite males continued to rep r o d u c e for another t w o years (x = 39.57, _+4.81, n = 459, t = 2.73, df = 499, p < .01). This c o m p a r i s o n is based on "biologically c o m p l e t e d " first marriages, which lasted at least until the wife's forty-fifth birthday. Birth intervals. M e a n birth intervals w e r e 28.7 m o n t h s (_+ 14.79, n = 238 intervals) within "biologically c o m p l e t e d " elite families, as c o m p a r e d to 34.3 m o n t h s (+ 18.2, n = 2056 intervals) in non-elite families. T h e rate of r e p r o d u c t i o n w a s thus higher in elite m a r r i a g e s (t = 5.39, df = 321, p < .001). A c o m p a r i s o n of the m e a n birth intervals p e r family (D15paquier a n d Lachiver categories, Figure 3) s h o w s as well that the w i v e s of elite m e n a d o p t e d a faster rate of giving birth t h a n the w i v e s of the non-elite m e n (Ha = 18.27, df = 3, p < .001).
Table 1. Distribution of Total Number of Marriages per Ever-married Man (Krummh6rn, Germany, 1760-1810)
Total Number of Marriages 1
% Elite men Non-elitemen
2
(n)
81.7 (49) 83.7 (798)
%
3
(n)
13.3 (8) 15.1 (144)
%
(n)
5.0 (3) 1.3 (12)
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49+ months
I--1 31-48 months 19-30 months -18 months
non- elite
elite
Figure 3. Distribution of mean birth intervals within elite and non-elite "biologically completed" first marriages (Krummh6rn, Germany, 1760-1810).
Infant and Child Survival
Stillbirths. The w i v e s of the elite e x p e r i e n c e d a stillbirth rate of .015 (N = 395 births), w h i c h is significantly l o w e r (z = 2.278, p < .05) t h a n the stillbirth rate of the non-elite p o p u l a t i o n of .037 (N = 4376 births). Infant survivorship. Infant m o r t a l i t y (both sexes c o m b i n e d ) a m o u n t e d to .195 in elite families, w h e r e a s the non-elite m e a n w a s .134 (z = 3.224, p < .01) (Figure 4). The m a l e infant m o r t a l i t y level of .230 in elite families in p a r t i c u l a r w a s far higher t h a n the m e a n of .144 in non-elite families (z = 3.413, p < .001). Thus, male infant m o r t a l i t y t e n d e d to be e v e n m o r e p r o n o u n c e d in elite families than in w e a l t h y f a r m e r s ' families (see Voland a n d D u n bar 1995 a n d Voland et al. 1991 for figures a n d e v o l u t i o n a r y e x p l a n a tion). A l t h o u g h female infant m o r t a l i t y t e n d e d to be higher w i t h i n elite families as well, the difference f r o m the m e a n in non-elite families d o e s not reach statistical significance.
KrummhOrn Above-Average Reproductive Success
229
0.8 non-elite 0"75t elite 0.7ot:xO 0
0.65 ',~'?i'i'i,] ,,,,.-,,,;
.% 0.6-
s .I.>
,%.;.-;., ",;..;,"
0.55
,,qq,
0.5 ,q,.q,,q~ ,,,qq
0.45 0.4-
mah:
female
both sexes
Figure 4. Male and female infant mortality (lq) by social class (Krummh6rn, Germany, 1760-1810). Total child mortality b e t w e e n the ages of 1 and 15 years (both sexes combined) was .185 (N = 3650) in non-elite families and .201 (N = 313) in elite families (z = .699, ns). Therefore differences in children's survival to age 15 (Figure 5) are mainly d u e to differences in infant mortality.
Social Placement As the K r u m m h 6 r n church registers contain no records on the reproductive history of those p e o p l e w h o left their natal parishes, the life histories of emigrants necessarily remain u n k n o w n . Therefore the fate of surviving 15-year-old children can only be classified according to the three following possibilities: either they r e m a i n e d at h o m e a n d died as singles (in which case the church registers contain only an entry of d e a t h or burial but n o n e of marriage or banns), they e m i g r a t e d as singles (in which case there is neither an entry of marriage or banns n o r of death),
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non-elite elite
l
~o
r~
';';'5;-;
.
male Figure 5.
.
.
female
.
[
.
.
.
.
both sexes
Infant survivorship (115) by social class (Krummhorn, Germany,
1760-1810). Table 2.
The Fate of 15-year-old Children from Elite and Non-elite Families (Krummh6rn, Germany, 1760-1810) Elite
Surviving children (15+ years), sample size Of these remained unmarried (%) emigrated unmarried (%) married locally (%)
Non-elite
m
f
both
m
f
both
122
128
250
1,501
1 , 4 6 9 2,970
12.3 23.0 64.8
10.2 10.2 79.7
11.2 16.4 72.4
12.7 29.4 57.8
11.2 24.7 64.1
12.0 27.1 60.9
or they m a r r i e d locally (in w h i c h case the m a r r i a g e or b a n n s are d o c u m e n t e d in the church registers) (Table 2). Because they w e r e less likely to e m i g r a t e for e c o n o m i c reasons, the children of the elite enjoyed a greater p r o b a b i l i t y of m a r r i a g e as c o m p a r e d w i t h the offspring f r o m o r d i n a r y families (z = 3.303, p < .005). This difference is especially striking w i t h regard to d a u g h t e r s (z = 3.146, p
The wealthy elite males of nineteenth-century K r u m m h 6 r n (Ostfriesland, Germany) achieved an above-average reproductive success. M e m b e r s h i p in the elite class was determined from a list of the 300 richest m e n in the Ostfriesland district compiled by authorities in 1812. The m a i n c o m p o n e n t s establishing the l i n k between cultural success and reproductive success are 1.
2.
3.
differences in the n u m b e r of o f f s p r i n g o w i n g to differences b o t h in time s p e n t in fecund marriage (mating success) a n d in rate of reproduction; differences in the p r o b a b i l i t i e s of one's a d u l t o f f s p r i n g m a r r y i n g locally vs. e m i g r a t i n g u n m a r r i e d o w i n g to differential a b i l i t y to allocate resources that e n h a n c e the "social p l a c e m e n t " of a d u l t offspring; a n d differences in the p r o b a b i l i t y of total r e p r o d u c t i v e failure (lineage extinction).
Contrary to w h a t m i g h t be expected, infant s u r v i v o r s h i p was l o w e s t a m o n g s t the richest families. We conclude that to a great extent f e m a l e s ' reproductive decisions contribute to the greater r e p r o d u c t i v e success of the elite males. KEY WORDS: Reproductive strategies; C u l t u r a l / r e p r o d u c t i v e success; Differential male m a t i n g success; F e m a l e r e p r o d u c t i v e decisions; Lineage extinction; E v o l u t i o n a r y d e m o g r a p h y ; K r u m m h 6 r n (Germany). Received January 23, 1995; accepted March 10, 1995. Address all correspondence to Eckart Voland, Zentrum fiir Philosophie und Grundlagen der Wissenschaft, Universitdt Giessen, Otto-Behaghel-Strasse 10 C/II, D-35394 Giessen, Germany. Copyright 9 1995 by Walter de Gruyter, Inc. New York Human Nature, Vol. 6, No. 3, pp. 221-240. 221
1045-6767/95/$1.00 + .10
222
Human Nature, Vol. 6, No. 3, 1995
Ever since Irons (1979) published his data on the positive correlation of personal wealth with individual reproductive success among Yomut Turkmen, major research efforts have been undertaken to verify or to dismiss the widely disputed assumption of the general applicability of his principal result to other societies. Some 15 years of research now suggest that in many historical and contemporary non-industrial populations, the cultural success/reproductive success link actually has an evolutionary explanation (for reviews, see Betzig 1986; Cronk 1991; Irons 1993; Low 1993; P6russe 1993). Whether or not this correlation persists in industrial societies is a matter of some doubt (P6russe 1993; Vining 1986). Factors that are known to establish fitness differentials among men in traditional and historical populations include 9 differential mating success (with respect to the number of wives in polygynous populations (e.g., Borgerhoff Mulder 1987); wives' reproductive value [age] in monogamous populations (e.g., Roskaft et al. 1992); extramarital matings (e.g., Flinn 1986); and remarriage (e.g., Boone 1986), 9 differential marital fertility (e.g., Irons 1979), 9 differential infant and child survivorship (e.g., Hughes 1986), and finally 9 differential allocation of marriage and reproductive chances ("social placement") of one's adult offspring presumably by means of inheritance and dowry payments (e.g., Roskaft et al. 1992). Although previous historical demographic analyses of the eighteenth- and nineteenth-century Krummh6rn population (Ostfriesland, Germany) revealed that here too cultural success (as measured by landownership) correlated positively with reproductive success (Voland 1990; Voland and Engel 1990), neither the relative significance of the single fitness components nor the actual causes of the correlation are well understood. With this study we aim to uncover the reproductive strategy adopted by the 1812 Krummh6rn elite men that eventually enabled them to achieve an increased reproductive success. We analyze their life- and reproductive histories and compare them with those of the non-elite male population to determine the specific demographic components (i.e., fertility, infant survivorship, or social placement of surviving offspring) that systematically contribute to fitness differentials within the population. With this, we aim at three insights:
Krummhi~rn Above-Average Reproductive Success
223
1. A reconstruction of the K r u m m h 6 r n social structure based on a historical source that provides the n a m e s of the 300 richest m e n in the Ostfriesland district allows us to check the validity of our p r e v i o u s social classification scheme, which was created on a c o m p a r a t i v e basis only. 2. A comprehensive u n d e r s t a n d i n g of the c o m p o n e n t s of differential reproduction enables us to d e t e r m i n e which evolved mechanisms have to be taken into account in comparisons of h u m a n reproductive performance. 3. Both of the previous insights can help us to u n d e r s t a n d w h o or w h a t caused the increased r e p r o d u c t i v e success of the male elite.
MATERIAL A N D METHODS The Krummh6rn Families This investigation is based on a family reconstitution in the eighteenth- and nineteenth-century K r u m m h 6 r n population. The K r u m m h6rn region is situated in the n o r t h w e s t of Ostfriesland ( G e r m a n y ) and comprises an area of 153 k m 2 (Figure 1) and a nearly stable cross-sectional
Figure 1. The location of the Krummh6rn.
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Human Nature, Vol. 6, No. 3, 1995
population size of approximately 14,000 individuals during the eighteenth and nineteenth centuries. Its soil ("younger marsh") is extremely fertile and allows for a highly productive agricultural and dairy farming system. Large and medium-sized businesses dominated the farming economy during the eighteenth and nineteenth centuries. A capital- and market-oriented agricultural system was able to develop early in this area and replaced a pure subsistence economy earlier than elsewhere in Germany. Accumulation of proceeds led to remarkable concentrations of wealth in some lineages. As a normative rule, but by no means automatically, the youngest son inherited the farm from his father (ultimogeniture). The heir had to pay compensation to his siblings, with each sister receiving only half of what each brother could expect. Because of its geographic situation (surrounded by the North Sea and by inaccessible moorlands), the population was unable to expand either its geographical area or its population size. The very early and complete colonization of the area prevented any significant population increase, since absolutely no commons or wasteland was available. It was access to land that determined the social structure of this population. If a farmer possessed at least 25 "Grasen" of land on his o w n (1 "Gras" = approx. 0.37 ha), or if he had at least 50 "Grasen" on lease, he was entitled to vote and to hold political and church offices. Thus, access to land defined social prestige, political influence and rights, and, of course, the everyday transactions of the people. The social class contrast between farmers and laborers was extremely marked in nearly every material and nonmaterial aspect of lifestyle. Thinking, feeling, and behaving according to social differences were underlined by the prevailing Calvinist religion, which tended to promote attitudes of social inequality. Social historians describe the rural Krummh6rn society as a "farmers' aristocracy" (Swart 1910: Bauernaristokratie). The extreme gap between farmers' and laborers' opportunities was noted by everybody and finally led to social dissatisfaction on the part of the working class during the course of the nineteenth century (Engel 1990 provides more details and further references). The entries from church registers in 13 of a total of 32 Krummh6rn parishes (Figure 2) were assigned to family lineages according to the standards of historical demography (e.g., Henry and Blum 1988). In comparison with other European regions, church registration started relatively late in this area, often not until the end of the seventeenth or even the beginning of the eighteenth century. By and large, registration is complete and sufficiently reliable from 1720 onwards. The likely gaps in the registration of stillbirths prior to 1750 do not affect the present study. The data were organized with the KLEIO databank system and analyzed by SPSS-x routines.
Krummhorn Above-Average Reproductive Success
225
KRUMMHORN
)persum
N
~den 012
Km
Figure 2. The parishes of the Krummhbrn (filled circles denote parishes in the "Krummh6rn data base"). The Samples In 1812, when Ostfriesland was under Napoleon's rule, the French authorities compiled a list of the 300 absolutely wealthiest men (as revealed by tax payments) to determine which persons were eligible to be members of the regional parliament. Because this list also contains places of residence, we are able to identify the 83 men who lived in the Krummh6rn area of Ostfriesland. We regard this sample as the 1812 Krummh6rn wealthy male elite. The data from parishes in which 43 of these 83 men lived had already been entered into the data base. In order to maximize sample size, a selective search was made in the remaining church registers for entries of vital and reproductive events relating to the other 40 men. Although we were eventually able to trace the life histories of 80 of the 83 men listed (96.4%), two of them died unmarried and thus were excluded from further analysis. Hence, the elite sample comprises 78 married men (see Appendix for names and places of residence). We contrast the reproductive data of the elite men with those from the male married population at large (non-elite sample). As all of the 78
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elite m e n contracted their first marriage b e t w e e n 1760 and 1810, w e accordingly limited the p o p u l a t i o n s a m p l e to those m e n w h o m a r r i e d for the first time d u r i n g the same time span. This selection led to a sample size of 954 non-elite m e n w h o s e r e p r o d u c t i v e histories can be regarded as completely k n o w n (see below). The ratio of 954 non-elite m e n to 22 elite m e n with c o m p l e t e l y k n o w n reproductive histories in the K r u m m h 6 r n data base indicates that the elite sample represents 2.25% of the total p o p u l a t i o n of m a r r i e d men. A r e p r o d u c t i v e history is considered to be c o m p l e t e l y k n o w n only if both the beginnings and the ends of all of a person's marriages are docu m e n t e d in the church records. The b e g i n n i n g of a marriage is indicated b y an entry for either the w e d d i n g or the banns. The end of a m a r r i a g e is defined b y the death of one or both spouses (providing it was k n o w n that the deceased's spouse had definitely not d i e d earlier). U n d e r these rather restrictive conditions, migration is unlikely to be a c o n f o u n d i n g factor and thus all births and deaths occurring in these families are k n o w n with near certainty. According to these criteria, the r e p r o d u c t i v e histories of 60 elite and 954 non-elite m e n can be r e g a r d e d as c o m p l e t e l y k n o w n . O w i n g to long-range mobility on the part of s o m e of the population, however, the reproductive histories of 18 elite m e n r e m a i n incomplete. Moreover, a marriage is considered to be biologically complete if it lasted at least until the wife's forty-fifth birthday. This category of reproductive history additionally requires the wife's exact birthdate to be k n o w n , and as usual in historical d e m o g r a p h y only first marriages of b o t h spouses are considered in that case. The influence of mortality on such fertility measures as age at last birth or m e a n length of birth intervals is thus excluded.
RESULTS: C O M P O N E N T S OF DIFFERENTIAL REPRODUCTIVE SUCCESS
Fertility and Its Determinants
Number of offspring. On average, m a r r i e d elite m e n had a m e a n of 6.58 (_+ 2.84, n = 60) children (including stillbirths), w h i c h is significantly m o r e than the non-elite m e a n (x = 4.59, + 2.85, n = 954, t = 13.40, df = 1012, p < .001). Two factors that contribute to the greater n u m b e r of offspring a m o n g elite m e n can be determined: the n u m b e r of years spent in f e c u n d marriage and the rate of reproduction.
KrummhOrn Above-Average Reproductive Success
227
Years spent in fecund marriage. C o m p u t i n g the n u m b e r of y e a r s s p e n t in fecund m a r r i a g e b y a d d i n g all of the y e a r s d u r i n g w h i c h a m a n w a s m a r r i e d to a w o m a n u n d e r the a g e of 45 yields an interesting outcome: elite m e n are able to m o n o p o l i z e 21.43 (+ 6.35, n = 60) y e a r s of f e m a l e fecundity, w h e r e a s non-elite m e n e n d e d u p w i t h only 17.33 y e a r s on average (_+ 7.94, n = 923, t = 4.77, df = 72, p < .001). A l t h o u g h c o m p a r i s o n of the contribution of second a n d third m a r r i a g e s to total y e a r s s p e n t in f e c u n d m a r r i a g e did not reveal any significant differences b e t w e e n the s a m p l e s (Table 1, X2 = .329, df = 1, ns), the h i g h e r m a t i n g success of elite m e n is c o m p l e t e l y d u e to their first w i v e s ' y o u n g e r ages. Elite m e n ' s brides h a d a m e a n age of 22.44 years (_+ 3.31, n = 64) a n d thus w e r e significantly y o u n g e r t h a n the p o p u l a t i o n m e a n (~ = 26.70, _+5.29, n = 962, t = 9.52, df = 86.8, p < .001). These figures agree w i t h the results r e p o r t e d b y Voland a n d Engel (1990). Women's age at last birth. The w i v e s of the elite males started h a v i n g children sooner, but they s t o p p e d sooner as well. Their m e a n age at last birth w a s 37.47 (_+ 4.41, n = 42), whereas the w i v e s of non-elite males continued to rep r o d u c e for another t w o years (x = 39.57, _+4.81, n = 459, t = 2.73, df = 499, p < .01). This c o m p a r i s o n is based on "biologically c o m p l e t e d " first marriages, which lasted at least until the wife's forty-fifth birthday. Birth intervals. M e a n birth intervals w e r e 28.7 m o n t h s (_+ 14.79, n = 238 intervals) within "biologically c o m p l e t e d " elite families, as c o m p a r e d to 34.3 m o n t h s (+ 18.2, n = 2056 intervals) in non-elite families. T h e rate of r e p r o d u c t i o n w a s thus higher in elite m a r r i a g e s (t = 5.39, df = 321, p < .001). A c o m p a r i s o n of the m e a n birth intervals p e r family (D15paquier a n d Lachiver categories, Figure 3) s h o w s as well that the w i v e s of elite m e n a d o p t e d a faster rate of giving birth t h a n the w i v e s of the non-elite m e n (Ha = 18.27, df = 3, p < .001).
Table 1. Distribution of Total Number of Marriages per Ever-married Man (Krummh6rn, Germany, 1760-1810)
Total Number of Marriages 1
% Elite men Non-elitemen
2
(n)
81.7 (49) 83.7 (798)
%
3
(n)
13.3 (8) 15.1 (144)
%
(n)
5.0 (3) 1.3 (12)
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49+ months
I--1 31-48 months 19-30 months -18 months
non- elite
elite
Figure 3. Distribution of mean birth intervals within elite and non-elite "biologically completed" first marriages (Krummh6rn, Germany, 1760-1810).
Infant and Child Survival
Stillbirths. The w i v e s of the elite e x p e r i e n c e d a stillbirth rate of .015 (N = 395 births), w h i c h is significantly l o w e r (z = 2.278, p < .05) t h a n the stillbirth rate of the non-elite p o p u l a t i o n of .037 (N = 4376 births). Infant survivorship. Infant m o r t a l i t y (both sexes c o m b i n e d ) a m o u n t e d to .195 in elite families, w h e r e a s the non-elite m e a n w a s .134 (z = 3.224, p < .01) (Figure 4). The m a l e infant m o r t a l i t y level of .230 in elite families in p a r t i c u l a r w a s far higher t h a n the m e a n of .144 in non-elite families (z = 3.413, p < .001). Thus, male infant m o r t a l i t y t e n d e d to be e v e n m o r e p r o n o u n c e d in elite families than in w e a l t h y f a r m e r s ' families (see Voland a n d D u n bar 1995 a n d Voland et al. 1991 for figures a n d e v o l u t i o n a r y e x p l a n a tion). A l t h o u g h female infant m o r t a l i t y t e n d e d to be higher w i t h i n elite families as well, the difference f r o m the m e a n in non-elite families d o e s not reach statistical significance.
KrummhOrn Above-Average Reproductive Success
229
0.8 non-elite 0"75t elite 0.7ot:xO 0
0.65 ',~'?i'i'i,] ,,,,.-,,,;
.% 0.6-
s .I.>
,%.;.-;., ",;..;,"
0.55
,,qq,
0.5 ,q,.q,,q~ ,,,qq
0.45 0.4-
mah:
female
both sexes
Figure 4. Male and female infant mortality (lq) by social class (Krummh6rn, Germany, 1760-1810). Total child mortality b e t w e e n the ages of 1 and 15 years (both sexes combined) was .185 (N = 3650) in non-elite families and .201 (N = 313) in elite families (z = .699, ns). Therefore differences in children's survival to age 15 (Figure 5) are mainly d u e to differences in infant mortality.
Social Placement As the K r u m m h 6 r n church registers contain no records on the reproductive history of those p e o p l e w h o left their natal parishes, the life histories of emigrants necessarily remain u n k n o w n . Therefore the fate of surviving 15-year-old children can only be classified according to the three following possibilities: either they r e m a i n e d at h o m e a n d died as singles (in which case the church registers contain only an entry of d e a t h or burial but n o n e of marriage or banns), they e m i g r a t e d as singles (in which case there is neither an entry of marriage or banns n o r of death),
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non-elite elite
l
~o
r~
';';'5;-;
.
male Figure 5.
.
.
female
.
[
.
.
.
.
both sexes
Infant survivorship (115) by social class (Krummhorn, Germany,
1760-1810). Table 2.
The Fate of 15-year-old Children from Elite and Non-elite Families (Krummh6rn, Germany, 1760-1810) Elite
Surviving children (15+ years), sample size Of these remained unmarried (%) emigrated unmarried (%) married locally (%)
Non-elite
m
f
both
m
f
both
122
128
250
1,501
1 , 4 6 9 2,970
12.3 23.0 64.8
10.2 10.2 79.7
11.2 16.4 72.4
12.7 29.4 57.8
11.2 24.7 64.1
12.0 27.1 60.9
or they m a r r i e d locally (in w h i c h case the m a r r i a g e or b a n n s are d o c u m e n t e d in the church registers) (Table 2). Because they w e r e less likely to e m i g r a t e for e c o n o m i c reasons, the children of the elite enjoyed a greater p r o b a b i l i t y of m a r r i a g e as c o m p a r e d w i t h the offspring f r o m o r d i n a r y families (z = 3.303, p < .005). This difference is especially striking w i t h regard to d a u g h t e r s (z = 3.146, p
