What have humans done for evolutionary biology? Contributions from genes to populations

Abstract

Many fundamental concepts in evolutionary biology were discovered using non-human study systems. Humans are poorly suited to key study designs used to advance this field, and are subject to cultural, technological, and medical influences often considered to restrict the pertinence of human studies to other species and general contexts. Whether studies using current and recent human populations provide insights that have broader biological relevance in evolutionary biology is, therefore, frequently questioned. We first surveyed researchers in evolutionary biology and related fields on their opinions regarding whether studies on contemporary humans can advance evolutionary biology. Almost all 442 participants agreed that humans still evolve, but fewer agreed that this occurs through natural selection. Most agreed that human studies made valuable contributions to evolutionary biology, although those less exposed to human studies expressed more negative views. With a series of examples, we discuss strengths and limitations of evolutionary studies on contemporary humans. These show that human studies provide fundamental insights into evolutionary processes, improve understanding of the biology of many other species, and will make valuable contributions to evolutionary biology in the future.

General conclusion to the special issue Moving forward on individual heterogeneity

“…This suggests that contrasting slow-fast species could provide far-reaching insights on the influences of changes in environmental conditions (Smallegange et al 2014). In addition, extremely long and detailed time series have been collected for some species like humans (Briga et al 2017), primates (Bronikowski et al 2016), ungulates (FestaBianchet et al 2017), or seabirds (Wooller et al 1992), making it possible to also study gradual changes in individual heterogeneity through time (Hartemink et al 2017, Caswell andVindenes 2018).…”

Humans as a model for understanding biological fundamentals

“…Similarly, research initially aimed at understanding traits often believed to be uniquely human, including some aspects of cooperation [27], menopause and a prolonged post-reproductive lifespan [26], and culture [28], has now revealed similar characteristics in other species. These contributions provide empirical examples of how a human model has demonstrably enabled a deeper understanding of the biology of other species and thereby illustrate how research on humans has fundamentally altered our perception of what makes us human, and what is not unique to us.…”

“…Indeed, Briga et al [26] show how research tools first developed to gain a deeper understanding of the dynamics of human populations (demography) and the importance of genes versus environment (i.e. nature versus nurture) in shaping individual variation (quantitative genetics) have now successfully been applied to a wide range of non-human species and questions.…”

“…B 284: 20172146 together a group of authors that is not representative of biologists in general. To gain a more representative picture of the prevailing opinion on the value of research on humans and its ability to address general biological questions, Briga et al [26] therefore chose to poll the evolutionary biology community. Although they received encouragingly positive responses, a significant proportion of the respondents nevertheless expressed some scepticism, raising the problems posed by the inability to perform experimental manipulations, and our unique and arguably unnatural environment.…”

Humans as model organisms

“…But nonetheless, human teeth and human digestive systems depend on the same mechanical and chemical systems found in other animals. Moreover (as Michael Briga and his colleagues note) there is often quite detailed information on population history, making demographic and life history questions relatively empirically tractable [5].…”