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Abstract Global climate during the Holocene was relatively stable compared to the late Pleistocene. However, evidence from lacustrine records in South America suggests that tropical latitudes experienced significant water balance variability during the Holocene, rather than quiescence. For example, a tight coupling between insolation and carbonate δ18O records from central Andean lakes (e.g., Lakes Junín, Pumacocha) suggest water balance is tied directly to South American summer monsoon (SASM) strength. However, lake carbonate δ18O records also incorporate information about temperature and evaporation. To overcome this ambiguity, clumped and triple oxygen isotope records can provide independent constraints on temperature and evaporation. Here, we use clumped and triple oxygen isotopes to develop Holocene temperature and evaporation records from three central Andean lakes, Lakes Junín, Pumacocha, and Mehcocha, to build a more complete picture of regional water balance (P–E). We find that Holocene water temperatures at all three lakes were stable and slightly warmer than during the latest Pleistocene. These results are consistent with global data assimilations and records from the foothills and Amazon basin. In contrast, evaporation was highly variable and tracks SASM intensity. The hydrologic response of each lake to SASM depends greatly on the physical characteristics of the lake basin, but they all record peak evaporation in the early to mid‐Holocene (11,700 to 4,200 years BP) when regional insolation was relatively low and the SASM was weak. These results corroborate other central Andean records and suggest synchronous, widespread water stress tracks insolation‐paced variability in SASM strength.
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This content will become publicly available on March 1, 2026
Human–environment interactions in the Lake Junín basin: Fire, megafauna, deforestation, and domestication, from the peopling of the Andes to the Inca Empire
Human–environment interactions are a focus of interdisciplinary research in the high Andes, recently invigorated by sediment-core data from Lake Junín (Chinchaycocha). On the basis of these records, recent articles have argued that humans arrived in the Junín basin 13 thousand calibrated years ago (kya), set large-scale fires, and hunted Pleistocene megafauna to extinction. Declines in montane tree pollen beginning ~4 kya have been attributed to deforestation, camelid domestication, and agriculture on the high Andean puna. In this paper, we critically examine these arguments and contrast them with a compilation of archaeological data from the Lake Junín basin including 113 radiocarbon dates (12 unpublished), settlement patterns, camelid osteometry, macrobotanical remains, Inca period sites, and ethnographic and ethnohistoric descriptions of herding and farming. These data suggest that the earliest archaeological evidence for human occupation is not until ~11 kya, and there is no clear evidence for interaction with Pleistocene megafauna. Although the Junín basin is often cited as a center for camelid domestication in the middle Holocene, this claim remains tenuous, since osteometry struggles to distinguish wild and domestic camelids. Finally, ethnohistoric and ethnographic information offer no support for the argument that the basin was a "manufactured landscape" in the late Holocene. Moving forward, we recommend more careful consideration of (1) the mismatch of temporal resolution in paleoecological and archaeological chronologies, (2) the potential spatial mismatch in the catchment area of palaeoecological proxies and archaeological datasets, and (3) ambiguity in Sporormiella as a proxy for fauna and charcoal as a proxy for human activity. We suggest that future work on paleoecological proxies from 0.7 to 0.3 kya could be harnessed to build a comparative baseline, since these centuries saw large populations of humans and domesticated camelids near the lake. Our goal is to promote more robust reconstructions of human–environment interactions in the Lake Junín basin and elsewhere.
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- Award ID(s):
- 2345169
- PAR ID:
- 10632521
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Quaternary Science Reviews
- Volume:
- 351
- Issue:
- C
- ISSN:
- 0277-3791
- Page Range / eLocation ID:
- 109159
- Subject(s) / Keyword(s):
- Late Pleistocene Holocene Quaternary extinctions Prehistoric archaeology Camelid domestication Deforestation Inca empire
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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