loading page

NDVI Predicts Birth Seasonality in Historical Baja California Sur, Mexico
  • +10
  • Shane Macfarlan,
  • Ryan Schacht,
  • Izabella Bourland,
  • Savannah Kapp,
  • Trevor Glad,
  • Lauren Lewis,
  • Nathan Darmiento,
  • Tanner Clegg,
  • Cole Thorpe,
  • Taylor Peppelar,
  • Melissa Santiago,
  • Celeste Henrickson,
  • Kenneth Vernon
Shane Macfarlan
University of Utah
Author Profile
Ryan Schacht
East Carolina University
Author Profile
Izabella Bourland
University of Utah
Author Profile
Savannah Kapp
University of Utah
Author Profile
Trevor Glad
University of Utah
Author Profile
Lauren Lewis
University of Utah
Author Profile
Nathan Darmiento
University of Utah
Author Profile
Tanner Clegg
University of Utah
Author Profile
Cole Thorpe
University of Utah
Author Profile
Taylor Peppelar
University of Utah
Author Profile
Melissa Santiago
East Carolina University
Author Profile
Celeste Henrickson
University of Utah
Author Profile
Kenneth Vernon
University of Utah
Author Profile

Abstract

Birth seasonality is a phenomenon whereby populations can be characterized by a single month or season in which births peak. While non-human animal research suggests seasonal birth-pulses are related to variation in climate and local energy availability, social scientists debate the mechanisms responsible for it in humans. Here we investigate the role of precipitation, temperature, and energy availability on seasonal birth pulses using a historical dataset from the Baja California peninsula - a hot, arid desert that experiences seasonal fluctuations in temperature, precipitation, and energy associated with the North American Monsoonal. Analyses suggest that local energy availability (as measured through NDVI) predicts seasonal birth pulses, while temperature and precipitation do not; however, both are indirectly related to it through their direct effects on NDVI. Our analyses demonstrate the importance of local energy availability on human reproductive timing and suggest that human birth seasonality is a form of traditional ecological knowledge.