Historic and bioarchaeological evidence supports late onset of post-Columbian epidemics in Native California

Abstract

Catastrophic decline of Indigenous populations in the Americas following European contact is one of the most severe demographic events in the history of humanity, but uncertainty persists about the timing and scale of the collapse, which has implications for not only Indigenous history but also the understanding of historical ecology. A long-standing hypothesis that a continent-wide pandemic broke out immediately upon the arrival of Spanish seafarers has been challenged in recent years by a model of regional epidemics erupting asynchronously, causing different rates of population decline in different areas. Some researchers have suggested that, in California, significant depopulation occurred during the first two centuries of the post-Columbus era, which led to a “rebound” in native flora and fauna by the time of sustained European contact after 1769. Here, we combine a comprehensive prehistoric osteological dataset (n = 10,256 individuals) with historic mission mortuary records (n = 23,459 individuals) that together span from 3050 cal BC to AD 1870 to systematically evaluate changes in mortality over time by constructing life tables and conducting survival analysis of age-at-death records. Results show that a dramatic shift in the shape of mortality risk consistent with a plague-like population structure began only after sustained contact with European invaders, when permanent Spanish settlements and missions were established ca. AD 1770. These declines reflect the syndemic effects of newly introduced diseases and the severe cultural disruption of Indigenous lifeways by the Spanish colonial system.

A genomic perspective on South American human history

“…Some studies suggest that this exponential rate of growth was maintained until the arrival of Europeans, at least in Amazonia (Arroyo-Kalin, 2018), while others indicate a slowdown in growth or even a decrease in population size in some areas, possibly due to having reached carrying capacity, autochthonous diseases, or even climate and social change (Arroyo-Kalin and Riris, 2021;Bush et al, 2021). However, as expected, the majority of genetic and archeological data pointed to the highest mortality rate occurring after Europeans arrived in the Americas, probably peaking later in the colonization period (Browning et al, 2018;Jones et al, 2021;Castro e Silva et al, 2022).…”

The Black Death in Hereford, England: A demographic analysis of the Cathedral 14th‐century plague mass graves and associated parish cemetery

“…While more commonly used in clinical trials, Kaplan–Meier analysis has been utilized to assess how survivorship in past populations was affected by stress markers (Boldsen, 2007; DeWitte, 2014a), disease (Yaussy & DeWitte, 2019), and temporospatial variation (DeWitte, 2015). Kaplan–Meier analysis has also been used to explore survivorship in catastrophic assemblages (DeWitte, 2014b, 2018; Jones et al, 2021). Kaplan–Meier survival curves were generated using the survival package in R and a log rank test was applied to each curve which calculated a chi‐squared value to quantify inter‐curve variation (R Core Team, 2023; RStudio Team, 2020; Therneau, 2023).…”

“…Kaplan-Meier analysis has also been used to explore survivorship in catastrophic assemblages (DeWitte, 2014b(DeWitte, , 2018Jones et al, 2021). Kaplan-Meier survival curves were generated using the survival package in R and a log rank test was applied to each curve which calculated a chi-squared value to quantify inter-curve variation (R Core Team, 2023; RStudio Team, 2020; Therneau, 2023).…”

Biocultural perspectives on bioarchaeological and paleopathological evidence of past pandemics

“…This is especially difficult when these variables are composed of multiple, intersecting social, ecological, and economic components. Doing so requires context and condition‐specific ethnographic, archeological, and/or historical data, which may be incomplete or absent, whether for recent pandemics (i.e., 1918 influenza pandemic) (Short et al, 2018) or those deeper in antiquity (e.g., the Black Death, Post‐contact Indigenous population decline) (Bos & DeWitte, 2022; DeWitte, 2018; Jones et al, 2021). The highly context‐specific effects of pandemics can further magnify this issue (e.g., Sattenspiel et al, 2019).…”