Intergenerational Effects: How maternal adversity impacts offspring

Adversities experienced by female baboons early in life can affect the survival of their offspring years later.
  1. Zaneta M Thayer  Is a corresponding author
  2. Chlöe A Sweetman
  1. Dartmouth College, United States

Surviving to adulthood is not an easy task, particularly for animals that live in the wild. For instance, among baboons born in and around Ambolesi National Park in Kenya, only 50% of females and 44% of males will make it to adulthood (Alberts, 2019). In order to survive, individuals must first be born healthy, have access to sufficient nutritional resources, and avoid predation. Baboons and other species, including humans, rely on the extensive care provided by parents to protect them from these challenges, and to teach them the skills they need to thrive in complex social and ecological environments. Given the important role that parents, particularly mothers, play in the growth, development, and survival of their offspring, what happens when mothers have themselves experienced significant challenges in their own early life?

Now, in eLife, Susan Alberts and co-workers at institutes in the US and Kenya – including Matthew Zipple (Duke University) as first author – report how adverse experiences in early life among female baboons affects offspring survival (Zipple et al., 2019). They analyzed data collected from wild baboons in and around Ambolesi Park across four decades, and measured various examples of adversity that had previously been associated with reduced survival among female baboons: maternal death; having a low social rank; experiencing high levels of competition for resources; being born in a drought; and having a close-in-age younger sibling (Tung et al., 2016). The data revealed that the challenges faced by the mother were more strongly associated with offspring survival than the offspring’s own experiences of adversity.

One explanation for this could be that offspring have evolved to be sensitive to cues their mother provides about the quality of the environment (Mousseau and Fox, 1998; Figure 1). The potential for these intergenerational effects is even greater in mammals, where pregnancy and breastfeeding allow for maternal biology to influence offspring development through the transfer of hormones. If mothers live in an environment with high adversity, maternal hormones can provide the offspring with ‘predictive’ cues about its future environment and change how the offspring grows and develops (Kuzawa, 2005).

Early adversity experienced by female baboons can have an impact on their offspring.

When a baboon experiences adversity in its environment (such as predation or a lack of food), there is an impact on its biology (such as its growth and development). Zipple et al. report that when a female baboon experiences adversity early in her life, there can be an impact on the survival of her offspring. Image credit: Chlöe Sweetman (CC BY 4.0)

Zipple et al. also found that offspring were less likely to reach adulthood if their mother’s own mother had died, or if their mother had a close-in-age younger sibling. This finding, however, is not consistent with the idea that changes to offspring biology are only caused by predictive cues provided by the mother. Instead, it illustrates how diminished access to resources in early life can have a cascading effect on survival that persists across generations (Figure 1). For example, female baboons faced with the loss of their own mother or the quick arrival of a resource-needy sibling could experience greater nutritional stress, which critically limits their growth and development (Gagliano and McCormick, 2007). As a result, when they become mothers these baboons may struggle to provide the resources their own offspring need.

While not investigated by Zipple et al., early adversity could also reduce the quality of maternal care. Early maternal death and the birth of a close-in-age sibling, for example, could result in an individual receiving less care, and not learning how to care for their own offspring. Finally, mothers who experienced early adversity are also more likely to experience early mortality, suggesting that offspring death may be a result of mothers no longer being able to directly protect and provide for their offspring (Zipple et al., 2019).

Work by Alberts on the same population of baboons has revealed that mothers who experienced early adversity were also more likely to be socially isolated from other females in adulthood (Alberts, 2019). As well as reducing their own survival, this social isolation could prevent female baboons from bonding with other mothers, which may influence the health and survival of their offspring. For example, reduced social bonds could result in less grooming of offspring, which could increase parasites, such as ticks. Grooming also affects microbiome diversity among baboons, suggesting that a reduction in communal grooming could lead to immune system or metabolism changes that impact the offspring’s health (Tung et al., 2015).

These findings suggest that the stressful environments experienced by a mother can negatively impact offspring survival. Future work should focus on investigating precisely how adversity early in life affects patterns of maternal care, and to what extent these effects influence the support and care non-mothers provide to offspring.

References

Article and author information

Author details

  1. Zaneta M Thayer

    Zaneta M Thayer is in the Department of Anthropology and Ecology, Evolution, Environment and Society Program, Dartmouth College, Hanover, United States

    For correspondence
    zaneta.marie.thayer@dartmouth.edu
    Competing interests
    No competing interests declared
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8028-942X
  2. Chlöe A Sweetman

    Chlöe A Sweetman is in the Department of Anthropology and Ecology, Evolution, Environment and Society Program, Dartmouth College, Hanover, United States

    Competing interests
    No competing interests declared
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4639-5215

Publication history

  1. Version of Record published: September 25, 2019 (version 1)

Copyright

© 2019, Thayer and Sweetman

This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.

Metrics

  • 1,255
    Page views
  • 111
    Downloads
  • 0
    Citations

Article citation count generated by polling the highest count across the following sources: Crossref, PubMed Central, Scopus.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Zaneta M Thayer
  2. Chlöe A Sweetman
(2019)
Intergenerational Effects: How maternal adversity impacts offspring
eLife 8:e51206.
https://doi.org/10.7554/eLife.51206
  1. Further reading

Further reading

    1. Ecology
    Luca Casiraghi, Francesco Mambretti ... Tommaso Bellini
    Research Article

    The understanding of eco-evolutionary dynamics, and in particular the mechanism of coexistence of species, is still fragmentary and in need of test bench model systems. To this aim we developed a variant of SELEX in vitro selection to study the evolution of a population of ∼1015 single-strand DNA oligonucleotide ‘individuals’. We begin with a seed of random sequences which we select via affinity capture from ∼1012 DNA oligomers of fixed sequence (‘resources’) over which they compete. At each cycle (‘generation’), the ecosystem is replenished via PCR amplification of survivors. Massive parallel sequencing indicates that across generations the variety of sequences (‘species’) drastically decreases, while some of them become populous and dominate the ecosystem. The simplicity of our approach, in which survival is granted by hybridization, enables a quantitative investigation of fitness through a statistical analysis of binding energies. We find that the strength of individual resource binding dominates the selection in the first generations, while inter- and intra-individual interactions become important in later stages, in parallel with the emergence of prototypical forms of mutualism and parasitism.

    1. Ecology
    Yongzhi Yan, Scott Jarvie, Qing Zhang
    Research Article

    Habitat loss and fragmentation per se have been shown to be a major threat to global biodiversity and ecosystem function. However, little is known about how habitat loss and fragmentation per se alters the relationship between biodiversity and ecosystem function (BEF relationship) in the natural landscape context. Based on 130 landscapes identified by a stratified random sampling in the agro-pastoral ecotone of northern China, we investigated the effects of landscape context (habitat loss and fragmentation per se) on plant richness, above-ground biomass, and the relationship between them in grassland communities using a structural equation model. We found that habitat loss directly decreased plant richness and hence decreased above-ground biomass, while fragmentation per se directly increased plant richness and hence increased above-ground biomass. Fragmentation per se also directly decreased soil water content and hence decreased above-ground biomass. Meanwhile, habitat loss decreased the magnitude of the positive relationship between plant richness and above-ground biomass by reducing the percentage of grassland specialists in the community, while fragmentation per se had no significant modulating effect on this relationship. These results demonstrate that habitat loss and fragmentation per se have inconsistent effects on BEF, with the BEF relationship being modulated by landscape context. Our findings emphasise that habitat loss rather than fragmentation per se can weaken the positive BEF relationship by decreasing the degree of habitat specialisation of the community.