About this Research Topic
Human activities can modify population sex ratios by affecting the full range of age demographics. In many species sex determination or embryonic survival is highly environmentally dependent. In addition to better-known examples of climate change influencing sex determination in reptiles and fish, increases in ambient temperature can also drive differential embryonic mortality between the sexes in some birds and mammals. In species where the sex ratios of early life stages are robust to environmental influence, human activities may still alter population sex ratios through differential mortality of adult males versus females. For example, in species where males and females rely on different habitats, have different home ranges, or have different dispersal patterns (e.g., some bats, damselflies, big cats, whales), habitat modification and degradation can disproportionately impact the survival of one sex. As such, it is crucial to consider how different species may be uniquely susceptible to skewed sex ratios as a result of anthropogenic activities.
The list of anthropogenic environmental changes with demonstrable influence on population sex ratios is ever-expanding, and introduction of non-native species, pollution, landscape modification, climate change, emerging infectious diseases, and commercial harvesting are some of the biggest offenders. Thus, it is important to comprehensively review how these anthropogenic effects alter sex ratios to better inform management and conservation efforts.
Though human activities often have unintended impacts on population sex ratios, there is growing exploration of intentional modification of population sex ratios for specific conservation and management outcomes. For example, head start programs are carefully considering the sex of the animals reared and released to achieve optimal population sex ratios. Further, the sex ratios of mosquito populations are being manipulated to control population growth and the spread of mosquito-borne pathogens. Learning how humans are both intentionally and unintentionally affecting the sex ratios of populations may shed light on the use of sex-ratio manipulation as a powerful management tool.
In this Research Topic, we aim to move beyond niche examples of sex-specific effects of human activities to highlight the pervasiveness of this issue across plant, animal, and human populations with the goal of making population sex ratios a research and conservation priority in the Anthropocene. We encourage a variety of contributions, such as review and mini-review papers, perspectives, meta-analyses, and original empirical and theoretical research articles. We welcome manuscripts across taxa that span anthropogenic activities within these three broad topics:
1. Anthropogenic effects on sex determination/ differential embryonic mortality
Examples include (but are not limited to):
• Climate change affecting sex ratios in species with environmental sex determination
• Human activities (e.g., climate change, pollution) influencing differential embryonic mortality of the sexes
2. Anthropogenic effects on adult sex ratios
Examples include (but are not limited to):
• Habitat degradation disproportionately affecting adult survival, habitat use, and/or dispersal in one sex
• Commercial harvesting (e.g., fishing) selectively impacting adults of one sex more than the other, triggering shifts in population dynamics and/or sex reversals
3. Human intervention
Examples include (but are not limited to):
• Intentionally skewing hatchling sex ratios in head start programs for conservation
• Manipulating the sex ratios of pest/invasive species/disease vectors to aid in management, conservation, and/or societal well-being (e.g., human health, food systems, etc.).
Keywords: skewed sex ratios, sex determination, climate change, habitat degradation, temperature
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.