1
|
Gettler LT, Samson DR, Kilius E, Sarma MS, Miegakanda V, Lew-Levy S, Boyette AH. Hormone physiology and sleep dynamics among BaYaka foragers of the Congo Basin: Gendered associations between nighttime activity, testosterone, and cortisol. Horm Behav 2023; 155:105422. [PMID: 37683498 DOI: 10.1016/j.yhbeh.2023.105422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 07/24/2023] [Accepted: 08/21/2023] [Indexed: 09/10/2023]
Abstract
Sleep quality is an important contributor to health disparities and affects the physiological function of the immune and endocrine systems, shaping how resources are allocated to life history demands. Past work in industrial and post-industrial societies has shown that lower total sleep time (TST) or more disrupted nighttime sleep are linked to flatter diurnal slopes for cortisol and lower testosterone production. There has been little focus on these physiological links in other socio-ecological settings where routine sleep conditions and nighttime activity demands differ. We collected salivary hormone (testosterone, cortisol) and actigraphy-based sleep data from Congolese BaYaka foragers (N = 39), who have relatively short and fragmented nighttime sleep, on average, in part due to their typical social sleep conditions and nighttime activity. The hormone and sleep data collections were separated by an average of 11.23 days (testosterone) and 2.84 days (cortisol). We found gendered links between nighttime activity and adults' hormone profiles. Contrary to past findings in Euro-American contexts, BaYaka men who were more active at night, on average, had higher evening testosterone than those with lower nighttime activity, with a relatively flat slope relating nighttime activity and evening testosterone in women. Women had steeper diurnal cortisol curves with less disrupted sleep. Men had steeper cortisol diurnal curves if they were more active at night. BaYaka men often hunt and socialize when active at night, which may help explain these patterns. Overall, our findings indicate that the nature of nighttime activities, including their possible social and subsistence contexts, are potentially important modifiers of sleep quality-physiology links, meriting further research across contexts.
Collapse
Affiliation(s)
- Lee T Gettler
- University of Notre Dame, Department of Anthropology, Notre Dame 46556, USA; University of Notre Dame, Eck Institute for Global Health, Notre Dame 46556, USA.
| | - David R Samson
- University of Toronto Mississauga, Department of Anthropology, Mississauga L5L1C6, Canada
| | - Erica Kilius
- University of Toronto Mississauga, Department of Anthropology, Mississauga L5L1C6, Canada
| | - Mallika S Sarma
- Johns Hopkins University, School of Medicine, Baltimore 21287, USA
| | - Valchy Miegakanda
- Laboratoire National de Sante Publique, Brazzaville, Republic of the Congo
| | - Sheina Lew-Levy
- Department of Psychology, Durham University, Durham DH1 3LE, UK
| | - Adam H Boyette
- Max Planck Institute for Evolutionary Anthropology, Department of Human Behavior, Ecology and Culture, Leipzig 04103, Germany
| |
Collapse
|
2
|
Gettler LT, Kuo PX, Sarma MS, Lefever JEB, Cummings EM, McKenna JJ, Braungart-Rieker JM. US fathers' reports of bonding, infant temperament and psychosocial stress based on family sleep arrangements. Evol Med Public Health 2022; 9:460-469. [PMID: 35154780 PMCID: PMC8830308 DOI: 10.1093/emph/eoab038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 11/09/2021] [Indexed: 11/17/2022] Open
Abstract
Background and objectives Evolutionary-grounded sleep research has been critical to establishing the mutual dependence of breastfeeding and nighttime sleep proximity for mothers and infants. Evolutionary perspectives on cosleeping also often emphasize the emotional motivations for and potential benefits of sleep proximity, including for parent-infant bonding. However, this potential link between infant sleep location and bonding remains understudied for both mothers and fathers. Moreover, in Euro-American contexts bedsharing has been linked to family stress and difficult child temperament, primarily via maternal reports. We know relatively little about whether paternal psychosocial dynamics differ based on family sleep arrangements, despite fathers and other kin often being present in the cosleeping environment across cultures. Here, we aim to help address some of these gaps in knowledge pertaining to fathers and family sleep arrangements. Methodology Drawing on a sample of Midwestern U.S. fathers (N=195), we collected sociodemographic and survey data to analyze links between infant nighttime sleep location, paternal psychosocial well-being, father-infant bonding, and infant temperament. From fathers’ reports, families were characterized as routinely solitary sleeping, bedsharing, or roomsharing (without bedsharing). Results We found that routinely roomsharing or bedsharing fathers, respectively, reported stronger bonding than solitary sleepers. Bedsharing fathers also reported that their infants had more negative temperaments and also tended to report greater parenting-related stress due to difficulties with their children. Conclusions These cross-sectional results help to highlight how a practice with deep phylogenetic and evolutionary history, such as cosleeping, can be variably expressed within communities with the potential for family-dependent benefits or strains. Evolutionary-grounded cosleeping research has elucidated the intimate connections between mother-infant sleep proximity and breastfeeding. However, some Euro-American research indicates that bedsharing can coincide with family strain and stress. Here, U.S. fathers who routinely roomshared or bedshared, respectively, reported stronger bonds to their babies than solitary sleeping fathers, but bedsharing fathers also reported more negative infant temperament.
Collapse
Affiliation(s)
- Lee T Gettler
- Department of Anthropology, University of Notre Dame, Notre Dame, IN, USA.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA.,William J. Shaw Center for Children and Families, University of Notre Dame, South Bend, IN, USA
| | - Patty X Kuo
- Department of Child, Youth and Family Studies, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Mallika S Sarma
- Department of Otolaryngology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | | | - E Mark Cummings
- William J. Shaw Center for Children and Families, University of Notre Dame, South Bend, IN, USA.,Department of Psychology, University of Notre Dame, Notre Dame, IN, USA
| | - James J McKenna
- Department of Anthropology, Santa Clara University, Santa Clara, CA, USA
| | - Julia M Braungart-Rieker
- Department of Human Development and Family Studies, Colorado State University, Fort Collins, CO, USA
| |
Collapse
|
3
|
Brick C, Hood B, Ekroll V, de-Wit L. Illusory Essences: A Bias Holding Back Theorizing in Psychological Science. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2021; 17:491-506. [PMID: 34283676 PMCID: PMC8902028 DOI: 10.1177/1745691621991838] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The reliance in psychology on verbal definitions means that psychological research is unusually moored to how humans think and communicate about categories. Psychological concepts (e.g., intelligence, attention) are easily assumed to represent objective, definable categories with an underlying essence. Like the “vital forces” previously thought to animate life, these assumed essences can create an illusion of understanding. By synthesizing a wide range of research lines from cognitive, clinical, and biological psychology and neuroscience, we describe a pervasive tendency across psychological science to assume that essences explain phenomena. Labeling a complex phenomenon can appear as theoretical progress before there is sufficient evidence that the described category has a definable essence or known boundary conditions. Category labels can further undermine progress by masking contingent and contextual relationships and obscuring the need to specify mechanisms. Finally, we highlight examples of promising methods that circumvent the lure of essences and suggest four concrete strategies for identifying and avoiding essentialist intuitions in theory development.
Collapse
Affiliation(s)
- C Brick
- Department of Psychology, University of Amsterdam.,Department of Psychology, University of Cambridge
| | - B Hood
- School of Psychological Science, University of Bristol
| | - V Ekroll
- Department of Psychosocial Science, University of Bergen
| | - L de-Wit
- Department of Psychology, University of Cambridge
| |
Collapse
|
4
|
Kilius E, Samson DR, Lew-Levy S, Sarma MS, Patel UA, Ouamba YR, Miegakanda V, Gettler LT, Boyette AH. Gender differences in BaYaka forager sleep-wake patterns in forest and village contexts. Sci Rep 2021; 11:13658. [PMID: 34211008 PMCID: PMC8249621 DOI: 10.1038/s41598-021-92816-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 06/16/2021] [Indexed: 11/09/2022] Open
Abstract
Sleep studies in small-scale subsistence societies have broadened our understanding of cross-cultural sleep patterns, revealing the flexibility of human sleep. We examined sleep biology among BaYaka foragers from the Republic of Congo who move between environmentally similar but socio-ecologically distinct locations to access seasonal resources. We analyzed the sleep-wake patterns of 51 individuals as they resided in a village location (n = 39) and a forest camp (n = 23) (362 nights total). Overall, BaYaka exhibited high sleep fragmentation (50.5) and short total sleep time (5.94 h), suggestive of segmented sleep patterns. Sleep duration did not differ between locations, although poorer sleep quality was exhibited in the village. Linear mixed effect models demonstrated that women's sleep differed significantly from men's in the forest, with longer total sleep time (β ± SE = - 0.22 ± 0.09, confidence interval (CI) = [- 0.4, - 0.03]), and higher sleep quality (efficiency; β ± SE = - 0.24 ± 0.09, CI = [- 0.42, - 0.05]). These findings may be due to gender-specific social and economic activities. Circadian rhythms were consistent between locations, with women exhibiting stronger circadian stability. We highlight the importance of considering intra-cultural variation in sleep-wake patterns when taking sleep research into the field.
Collapse
Affiliation(s)
- Erica Kilius
- Department of Anthropology, University of Toronto Mississauga, Mississauga, L5L1C6, Canada.
| | - David R Samson
- Department of Anthropology, University of Toronto Mississauga, Mississauga, L5L1C6, Canada.
| | - Sheina Lew-Levy
- Department of Psychology, Simon Fraser University, Burnaby, V5A1S6, Canada.,Department of Archaeology and Heritage Studies, Aarhus University, 8270, Højbjerg, Denmark
| | - Mallika S Sarma
- School of Medicine, Johns Hopkins University, Baltimore, 21287, USA
| | - Ujas A Patel
- Department of Anthropology, University of Toronto Mississauga, Mississauga, L5L1C6, Canada
| | - Yann R Ouamba
- Ecole Nationale Supérieure d'Agronomie et de Foresterie, Université Marien N'Gouabi, Brazzaville, Republic of the Congo
| | - Valchy Miegakanda
- Laboratoire National de Santé Publique, Brazzaville, Republic of the Congo
| | - Lee T Gettler
- Department of Anthropology, University of Notre Dame, Notre Dame, 46556, USA.,Eck Institute for Global Health, University of Notre Dame, Notre Dame, 46556, USA
| | - Adam H Boyette
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, 04103, Leipzig, Germany
| |
Collapse
|
5
|
Gettler LT, Lew-Levy S, Sarma MS, Miegakanda V, Boyette AH. Sharing and caring: Testosterone, fathering, and generosity among BaYaka foragers of the Congo Basin. Sci Rep 2020; 10:15422. [PMID: 32963277 PMCID: PMC7508877 DOI: 10.1038/s41598-020-70958-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 06/17/2020] [Indexed: 01/13/2023] Open
Abstract
Humans are rare among mammals in exhibiting paternal care and the capacity for broad hyper-cooperation, which were likely critical to the evolutionary emergence of human life history. In humans and other species, testosterone is often a mediator of life history trade-offs between mating/competition and parenting. There is also evidence that lower testosterone men may often engage in greater prosocial behavior compared to higher testosterone men. Given the evolutionary importance of paternal care and heightened cooperation to human life history, human fathers' testosterone may be linked to these two behavioral domains, but they have not been studied together. We conducted research among highly egalitarian Congolese BaYaka foragers and compared them with their more hierarchical Bondongo fisher-farmer neighbors. Testing whether BaYaka men's testosterone was linked to locally-valued fathering roles, we found that fathers who were seen as better community sharers had lower testosterone than less generous men. BaYaka fathers who were better providers also tended to have lower testosterone. In both BaYaka and Bondongo communities, men in marriages with greater conflict had higher testosterone. The current findings from BaYaka fathers point to testosterone as a psychobiological correlate of cooperative behavior under ecological conditions with evolutionarily-relevant features in which mutual aid and sharing of resources help ensure survival and community health.
Collapse
Affiliation(s)
- Lee T Gettler
- Department of Anthropology, University of Notre Dame, 244 Corbett Family Hall, Notre Dame, IN, 46556, USA.
- Eck Institute for Global Health, University of Notre Dame, Notre Dame, IN, USA.
- William J. Shaw Center for Children and Families, University of Notre Dame, South Bend, IN, USA.
| | - Sheina Lew-Levy
- Department of Psychology, Simon Fraser University, Burnaby, Canada
- Department of Archaeology and Heritage Studies, Aarhus University, Aarhus, Denmark
| | - Mallika S Sarma
- Department of Anthropology, University of Notre Dame, 244 Corbett Family Hall, Notre Dame, IN, 46556, USA
| | - Valchy Miegakanda
- Institut National de Santé Publique, Brazzaville, Republic of the Congo
| | - Adam H Boyette
- Department of Human Behavior, Ecology and Culture, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| |
Collapse
|
6
|
Gray PB, Straftis AA, Bird BM, McHale TS, Zilioli S. Human reproductive behavior, life history, and the Challenge Hypothesis: A 30-year review, retrospective and future directions. Horm Behav 2020; 123:104530. [PMID: 31085183 DOI: 10.1016/j.yhbeh.2019.04.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 04/29/2019] [Accepted: 04/30/2019] [Indexed: 12/22/2022]
Abstract
The Challenge Hypothesis (Wingfield et al., 1990) originally focused on adult male avian testosterone elevated in response to same-sex competition in reproductive contexts. The purpose of the present paper is to demonstrate how the Challenge Hypothesis has shaped ideas about human life histories. We conduct a citation analysis, drawing upon 400 Google Scholar citations in the human literature to identify patterns in this body of scholarship. We cover key factors, such as context and personality traits, that help explain variable testosterone responses such as winning/losing to adult competitive behavior. Findings from studies on courtship and sexual behavior indicate some variation in testosterone responses depending on factors such as motivation. A large body of research indicates that male testosterone levels are often lower in contexts of long-term committed partnerships and nurturant fathering and aligned with variation in male mating and parenting effort. As the Challenge Hypothesis is extended across the life course, DHEA and androstenedione (rather than testosterone) appear more responsive to juvenile male competitive behavior, and during reproductive senescence, baseline male testosterone levels decrease just as male life history allocations show decreased mating effort. We discuss how research on testosterone administration, particularly in older men, provides causal insight into effects of testosterone in humans, and how this "natural experiment" can be viewed in light of the Challenge Hypothesis. We synthesize central concepts and findings, such as an expanded array of costs of testosterone that inform life history tradeoffs between maintenance and reproductive effort, and we conclude with directions for future research.
Collapse
Affiliation(s)
- Peter B Gray
- Department of Anthropology, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, Box 455003, Las Vegas, NV 89154-5003, United States of America.
| | - Alex A Straftis
- Department of Anthropology, University of Nevada, Las Vegas, 4505 S. Maryland Parkway, Box 455003, Las Vegas, NV 89154-5003, United States of America
| | - Brian M Bird
- Department of Psychology, Simon Fraser University, Canada
| | - Timothy S McHale
- Department of Anthropology, Central Washington University, United States of America
| | - Samuele Zilioli
- Department of Psychology, Wayne State University, United States of America; Department of Family Medicine and Public Health Sciences, Wayne State University, United States of America.
| |
Collapse
|
7
|
de Vries EE, van der Pol LD, Vermeer HJ, Groeneveld MG, Fiers T, Mesman J. Testosterone and Fathers’ Parenting Unraveled: Links with the Quantity and Quality of Father-Child Interactions. ADAPTIVE HUMAN BEHAVIOR AND PHYSIOLOGY 2019. [DOI: 10.1007/s40750-019-00118-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Abstract
Objective
Individual differences in quality of father involvement in caregiving might in part be explained by fathers’ testosterone (T) levels. We examined the links between fathers’ (n = 32) salivary T levels, amount of time spent with their child (12–30 months of age), type of father-child interaction, and fathers’ sensitivity.
Methods
During two home visits, video observations of father-child interactions were conducted to measure fathers’ sensitivity during a challenging and harmonious interaction. Fathers’ saliva was collected several times throughout the day on a working day and on the home visit days, including right before and after each father-child interaction.
Results
Fathers’ T secretion throughout the day was lower on home visit days (i.e., days with a higher amount of time spent with their child) than on a working day. For both challenging and harmonious father-child interactions, mean T levels did not differ before and after father-child interactions. However, individual changes in fathers’ T levels during the father-child interactions did predict fathers’ sensitivity. Specifically, the more T increased during the challenging interaction, or decreased during the harmonious interaction, the more sensitive the father was during that interaction as well as during a subsequent interaction.
Conclusions
Parenting quality is most optimal when fathers’ T system reacts in the expected direction given the context of the father-child interaction, i.e., a T decrease during a harmonious interaction and a T increase during a challenging interaction. Our study underscores the importance of examining the interplay between biology, behavior, and caregiving context in fathers’ parenting.
Collapse
|
8
|
van der Pol LD, Groeneveld MG, van Berkel SR, Endendijk JJ, Hallers-Haalboom ET, Mesman J. Fathers: The interplay between testosterone levels and self-control in relation to parenting quality. Horm Behav 2019; 112:100-106. [PMID: 30978338 DOI: 10.1016/j.yhbeh.2019.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 03/12/2019] [Accepted: 04/08/2019] [Indexed: 12/18/2022]
Abstract
In this study, we examined the potential interaction effect between fathers' basal testosterone levels and their ability to control their impulses in relation to their quality of parenting. Participants included 159 fathers and their preschoolers. Evening and morning salivary samples were analyzed with isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) to determine basal testosterone (T) levels. During a home-visit, fathers' self-control was measured with a computerized Go/NoGo task, and their sensitivity and respect for child autonomy was observed in a free-play session. We found that higher T levels in the evening were related to less respect for child autonomy, but only in fathers with low self-control. Further, higher T in the evening was related to more sensitive parenting, yet only in fathers with high self-control. These findings indicate that different aspects of fathers' quality of parenting are differently affected by the interaction between T and self-control. Further research is needed to clarify the interplay between fathers' neuro-endocrine system functioning and their trait characteristics in relation to the development of father-child relationships.
Collapse
Affiliation(s)
| | | | | | | | | | - Judi Mesman
- Education and Child Studies, Leiden University, the Netherlands.
| |
Collapse
|
9
|
Gettler LT, Kuo PX, Rosenbaum S, Avila JL, McDade TW, Kuzawa CW. Sociosexuality, testosterone, and life history status: prospective associations and longitudinal changes among men in Cebu, Philippines. EVOL HUM BEHAV 2019. [DOI: 10.1016/j.evolhumbehav.2018.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
10
|
Rosenbaum S, Gettler LT, McDade TW, Bechayda SS, Kuzawa CW. Does a man's testosterone “rebound” as dependent children grow up, or when pairbonds end? A test in Cebu, Philippines. Am J Hum Biol 2018; 30:e23180. [DOI: 10.1002/ajhb.23180] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/25/2018] [Accepted: 08/07/2018] [Indexed: 12/18/2022] Open
Affiliation(s)
- Stacy Rosenbaum
- Department of Anthropology Northwestern University Evanston Illinois
| | - Lee T. Gettler
- Department of Anthropology University of Notre Dame Notre Dame Indiana
- Eck Institute for Global Health University of Notre Dame Notre Dame Indiana
| | - Thomas W. McDade
- Department of Anthropology Northwestern University Evanston Illinois
- Institute for Policy Research, Northwestern University Evanston Illinois
| | - Sonny S. Bechayda
- Office of Population Studies University of San Carlos Cebu Philippines
- Department of Anthropology, Sociology, and History University of San Carlos Cebu Philippines
| | - Christopher W. Kuzawa
- Department of Anthropology Northwestern University Evanston Illinois
- Institute for Policy Research, Northwestern University Evanston Illinois
| |
Collapse
|
11
|
Testosterone is Associated with Perceived Constraint in Early Fatherhood. ADAPTIVE HUMAN BEHAVIOR AND PHYSIOLOGY 2017. [DOI: 10.1007/s40750-017-0077-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|