TY - JOUR
T1 - Fatherhood, pairbonding and testosterone in the Philippines
AU - Kuzawa, Christopher W.
AU - Gettler, Lee T.
AU - Muller, Martin N.
AU - McDade, Thomas W.
AU - Feranil, Alan B.
N1 - Funding Information:
Linda Adair played an important role in designing and implementing the CLHNS survey from which these data and samples were obtained. Elizabeth Quinn, Katy Sharrock, Jeffrey Huang, Iram Azam, Divya Mallampati, Brian Dubin, and Laura Rogers helped with various phases of lab work with these samples. We thank the many researchers at the Office of Population Studies, University of San Carlos, Cebu, the Philippines, for their central role in study design and data collection, and the Filipino participants, who generously provided their time for this study. This study was funded by the Wenner Gren Foundation (Gr. 7356) and the National Science Foundation (BCS-0542182). Fieldwork and sample collection were supported by pilot funds from the Interdisciplinary Obesity Center (RR20649) and the Center for Environmental Health and Susceptibility (ES10126; project 7-2004-E).
PY - 2009/10
Y1 - 2009/10
N2 - In species with a high level of paternal care, including humans, testosterone (T) is believed to help mediate the trade-off between parenting and mating effort. This hypothesis is supported by the observation of lower T in pairbonded men or fathers compared to single, non-fathers; however, prior work has highlighted population variation in the association between T and pairbonding or fatherhood status. Here we evaluate this hypothesis in a large (n = 890), representative birth cohort of young men (age range 20.5-22.5 years) living in Cebu City, the Philippines. Bioavailable T was measured in saliva collected prior to bed and immediately upon waking the following morning. Plasma T and luteinizing hormone (LH) were measured in morning plasma samples. In this sample, 20% of men were pairbonded, defined as living with a partner or married, 13% were fathers, and roughly half of fathers reported involvement in childcare. Pairbonded men had significantly lower T at both times of day. Unlike in other populations, this relationship was accounted for entirely by fatherhood status: among the large sub-sample of non-fathers, mean T was nearly identical among pairbonded and single men. There was a strong association between self-reported involvement in childcare and lower evening T, supporting the idea that the evening nadir in T is related to social interactions across the day. Similar relationships were found for total plasma T and LH, suggesting that these relationships are coordinated by centrally-mediated changes in LH secretion. The relatively modest T difference in relation to fatherhood at Cebu, in comparison to other studies, may reflect a lower level of paternal involvement in childcare activities in this population. Our findings using a large, well-characterized birth cohort support the hypothesized role of T as a mediator of mating and parenting effort in humans, while contributing evidence for cultural variation in the relative importance of pairbonding and fathering to these relationships.
AB - In species with a high level of paternal care, including humans, testosterone (T) is believed to help mediate the trade-off between parenting and mating effort. This hypothesis is supported by the observation of lower T in pairbonded men or fathers compared to single, non-fathers; however, prior work has highlighted population variation in the association between T and pairbonding or fatherhood status. Here we evaluate this hypothesis in a large (n = 890), representative birth cohort of young men (age range 20.5-22.5 years) living in Cebu City, the Philippines. Bioavailable T was measured in saliva collected prior to bed and immediately upon waking the following morning. Plasma T and luteinizing hormone (LH) were measured in morning plasma samples. In this sample, 20% of men were pairbonded, defined as living with a partner or married, 13% were fathers, and roughly half of fathers reported involvement in childcare. Pairbonded men had significantly lower T at both times of day. Unlike in other populations, this relationship was accounted for entirely by fatherhood status: among the large sub-sample of non-fathers, mean T was nearly identical among pairbonded and single men. There was a strong association between self-reported involvement in childcare and lower evening T, supporting the idea that the evening nadir in T is related to social interactions across the day. Similar relationships were found for total plasma T and LH, suggesting that these relationships are coordinated by centrally-mediated changes in LH secretion. The relatively modest T difference in relation to fatherhood at Cebu, in comparison to other studies, may reflect a lower level of paternal involvement in childcare activities in this population. Our findings using a large, well-characterized birth cohort support the hypothesized role of T as a mediator of mating and parenting effort in humans, while contributing evidence for cultural variation in the relative importance of pairbonding and fathering to these relationships.
KW - Anthropology
KW - Challenge hypothesis
KW - Child care
KW - Evolution
KW - Luteinizing hormone
KW - Parenting effort
KW - Paternal care
KW - Reproductive ecology
KW - Salivary assays
KW - Steroids
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UR - http://www.scopus.com/inward/citedby.url?scp=70349789102&partnerID=8YFLogxK
U2 - 10.1016/j.yhbeh.2009.07.010
DO - 10.1016/j.yhbeh.2009.07.010
M3 - Article
C2 - 19651129
AN - SCOPUS:70349789102
VL - 56
SP - 429
EP - 435
JO - Hormones and Behavior
JF - Hormones and Behavior
SN - 0018-506X
IS - 4
ER -