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Cited by 91Pleistocene-Era Hominins and ArchaeologyArchaeology and ancient environmental studiesForensic and Genetic Research

The DOI matches its Crossref record; 50 of the 50 references it cites were found in a registry or an index; 11 of the 49 sources its claims cite were checked for support.

Pre-Clovis occupation of the Americas identified by human fecal biomarkers in coprolites from Paisley Caves, Oregon

Open access
Shillito, Lisa-Marie, Whelton, Helen L., Blong, John C., Jenkins, Dennis L., Connolly, Thomas J., Bull, Ian D.·2020·Science Advances
DOI 10.1126/sciadv.aba6404PMC PMC7363456
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Abstract

When and how people first settled in the Americas is an ongoing area of research and debate. The earliest sites typically only contain lithic artifacts that cannot be directly dated. The lack of human skeletal remains in these early contexts means that alternative sources of evidence are needed. Coprolites, and the DNA contained within them, are one such source, but unresolved issues concerning ancient DNA taphonomy and potential for contamination make this approach problematic. Here, we use fecal lipid biomarkers to demonstrate unequivocally that three coprolites dated to pre-Clovis are human, raise questions over the reliance on DNA methods, and present a new radiocarbon date on basketry further supporting pre-Clovis human occupation.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

Fecal lipid biomarkers (5β-stanols and bile acids) in coprolites from Paisley Caves, Oregon, confirm human origin for some pre-Clovis coprolites and support human occupation by 12,200 14C yr B.P. A newly dated bulrush basketry fragment at 12,273 ± 56 14C yr B.P. further supports the stratigraphic integrity of the pre-Clovis deposit.

Key findings

  • Of 21 coprolites analyzed, 10 were interpreted as human, 6 as carnivore, 1 as mixed human/carnivore, and 2 were inconclusive; 13 of 21 biomarker interpretations agreed with prior mtDNA classifications.
  • Of six pre-Clovis coprolites previously identified as human by mtDNA, three were confirmed as human by fecal biomarkers; coprolites 194 and 280 are the oldest coprolites determined to be unequivocally human by fecal biomarkers, dated to 12,140 ± 70 and 12,260 ± 60 14C yr B.P. (194) and 12,050 ± 25 and 12,165 ± 25 14C yr B.P. (280).
  • Human occupation at Paisley Caves is stated as proven to 12,200 14C yr B.P. using fecal lipid biomarkers; a bulrush artifact recovered above coprolite 185 dated to 12,273 ± 56 14C yr B.P., while coprolite 185 itself dated to 12,290 ± 60 and 12,345 ± 55 14C yr B.P.
  • Fecal sterol concentration decreased with age from 573 μg g−1 in the youngest coprolite to 9.5 μg g−1 in the oldest coprolite, with detection typically requiring >0.4 μg g−1 coprolite.

Methods

  • Twenty-one coprolites previously subjected to mtDNA analysis were subsampled; approximately 0.5 g was crushed, internal standards were added, lipids were microwave-extracted into 2:1 dichloromethane/CH3OH, hydrolyzed, and sterol and bile acid fractions were isolated and analyzed by GC and GC-MS.
  • Origin assignments followed criteria from Bull and coworkers; carnivore identifications were confirmed with a coprostanol/cholesterol ratio of <1 plus bile acid profiles showing predominance of deoxycholic acid and higher proportions of cholic acid. Multiple radiocarbon dates were combined using Oxcal 4.3 “R_combine.”
  • A bulrush shaft with S-twist twined basket or mat weft features was submitted for AMS radiocarbon analysis.

Limitations

  • Stated: two coprolites yielded inconclusive results, likely from a mixture of environmentally derived lipids and low fecal lipid preservation; six coprolites classified as human by mtDNA were classified as carnivore by biomarkers, possibly because about a quarter of North American subjects in a prior study showed little to no conversion of cholesterol to coprostanol, potentially causing false negatives.
  • Stated: one coprolite was interpreted as possible human/carnivore mixing due to a high proportion of CDCA; several coprolites share the same catalog number, so the authors cannot be 100% certain they analyzed the same coprolite as the mtDNA study; one coprolite was potentially carnivore but could not be confirmed due to lack of bile acids.
  • Evident: fecal biomarker analysis lacks the detailed information mtDNA can provide and depends on sufficient compound preservation; lipid degradation increases with age and aerobic burial conditions, and only 13 of 21 biomarker interpretations agreed with mtDNA.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1126/sciadv.aba6404

Cites

50 of 50 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

11 of 49 cited sources checked · 2 supported · 0 flagged · accuracy not yet measured

  • Interpretationcitation

    The lack of early human skeletal remains and the ethical issues associated with destructive analysis of the handful that have been discovered means that coprolites are the best direct archaeological evidence that people occupied a particular site.

    “The lack of early human skeletal remains, and the ethical issues associated with destructive analysis of the handful that have been discovered (46, 47), means that coprolites are the best direct archaeological evidence that people occupied a particular site.”
    Quote in the paperNot a substantial claim2 of 2 sources checked
    • cites [46] Callaway E., Ancient genome stirs ethics debate. Nature 506, 142– 143 (2014). 24522580 source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
    • cites [47] Rasmussen M., Anzick S. L., Waters M. R., Skoglund P., De Giorgio M., Stafford T. W. Jr., Rasmussen S., Moltke I., Albrechtsen A., Doyle S. M., Poznik G. D., Gudmundsdottir V., Yadav R., Malaspinas A.-S., White S. S. V, Allentoft M. E., Cornejo O. E., Tambets K., Eriksson A., Heintzman P. D., Karmin M., Korneliussen T. S., Meltzer D. J., Pierre T. L., Stenderup J., Saag L., Warmuth V. M., Lopes M. C., Malhi R. S., Brunak S., Sicheritz-Ponten T., Barnes I., Collins M., Orlando L., Balloux F., Manica A., Gupta R., Metspalu M., Bustamante C. D., Jakobsson M., Nielsen R., Willerslev E., The genome source

      Split into 2 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

      Experimental — accuracy not yet measured
  • Findingown data

    All of the coprolites analyzed are identifiable as intact structures.

    “All of the coprolites analyzed are identifiable as intact structures (figs. S4 and S5)”
    Quote in the paperSubstantial claim
  • Findingown data

    Of the six pre-Clovis coprolites identified as human by mtDNA, three are confirmed as human by fecal biomarker analysis.

    “Of the six pre-Clovis coprolites identified as human by mtDNA, three are confirmed as human by this analysis (Fig. 2 and Table 1)”
    Quote in the paperSubstantial claim
  • Findingown data

    A bulrush shaft with the features of an S-twist twined basket or mat weft fragment yielded a radiocarbon date of 12,273 ± 56 14C yr B.P.

    “yielded a radiocarbon date of 12,273 ± 56 14C yr B.P. (table S3)”
    Quote in the paperSubstantial claim
  • Findingown data

    There is a general trend toward the concentration of fecal sterols decreasing as radiocarbon age of the coprolite increases from 573 μg g−1 in the youngest coprolite to 9.5 μg g−1 in the oldest coprolite.

    “there is a general trend toward the concentration of fecal sterols decreasing as radiocarbon age of the coprolite increases from 573 μg g−1 in the youngest coprolite to 9.5 μg g−1 in the oldest coprolite.”
    Quote in the paperNot a substantial claim
  • It may state two separate claims as one. 27
  • Probably not a substantial claim. 13

  • It may state two separate claims as one.

    Premisecitation

    Coprolites contain complex mixtures of lipids derived from the producer organism, its diet and biochemical processes occurring in its gut; some lipids are diagnostic of fecal origin.

    “As well as being repositories of DNA, coprolites also contain complex mixtures of lipids derived from the producer organism, its diet and biochemical processes occurring in its gut; some lipids are diagnostic of fecal origin [e.g., (12, 13)].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [12] Bull I. D., Lockheart M. J., Elhmmali M. M., Roberts D. J., Evershed R. P., The origin of faeces by means of biomarker detection. Environ. Int. 27, 647– 654 (2002). 11934114 source
    • cites [13] Prost K., Birk J. J., Lehndorff E., Gerlach R., Amelung W., Steroid biomarkers revisited - improved source identification of faecal remains in archaeological soil material. PLOS ONE 12, e0164882 (2017). 28060808 PMC5217961 source

  • It may state two separate claims as one.

    Premisecitation

    The Paisley Caves contain coprolites dating to 12,400 14C yr B.P. identified as human on the basis that they contain human DNA.

    “The Paisley Caves contain additional evidence for pre-Clovis occupation in the form of coprolites dating to 12,400 14C yr B.P. identified as human on the basis that they contain human DNA (3, 5).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [3] Jenkins D. L., Davis L. G., Stafford T. W. Jr., Campos P. F., Hockett B., Jones G. T., Cummings L. S., Yost C., Connolly T. J., Yohe R. M. II, Gibbons S. C., Raghavan M., Rasmussen M., Paijmans J. L. A., Hofreiter M., Kemp B. M., Barta J. L., Monroe C., Gilbert M. T. P., Willerslev E., Clovis age Western Stemmed projectile points and human coprolites at the Paisley Caves. Science 337, 223– 228 (2012). 22798611 source
    • cites [5] Gilbert M. T. P., Jenkins D. L., Götherstrom A., Naveran N., Sanchez J. J., Hofreiter M., Thomsen P. F., Binladen J., Higham T. F. G., Yohe R. M. II, Parr R., Cummings L. S., Willerslev E., DNA from pre-Clovis human coprolites in Oregon, North America. Science 320, 786– 789 (2008). 18388261 source

      The indexed Abstract reports human mitochondrial DNA in directly dated coprolites from the Paisley 5 Mile Point Caves, supporting their identification as human and their pre-Clovis age. It gives the date as 12,300, not 12,400, radiocarbon years B.P.; searches for 12,400 found no matching passage in our copy. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Premisecitation

    DNA has been shown to be mobile in sediments in a range of environments and is relatively easy to degrade.

    “DNA has been shown to be mobile in sediments in a range of environments and is also relatively easy to degrade.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [6] Pedersen M. W., Overballe-Petersen S., Ermini L., Sarkissian C. D., Haile J., Hellstrom M., Spens J., Thomsen P. F., Bohmann K., Cappellini E., Schnell I. B., Wales N. A., Carøe C., Campos P. F., Schmidt A. M. Z., Gilbert M. T. P., Hansen A. J., Orlando L., Willerslev E., Ancient and modern environmental DNA. Philos. Trans. R. Soc. Lond. B Biol. Sci. 370, 20130383 (2015). 25487334 PMC4275890 source

  • It may state two separate claims as one.

    Interpretationcitation

    Fecal lipid biomarkers offer access to hitherto unknown or uncertain information, adding to the growing body of evidence about when and by what route people arrived and how these people adapted to diverse landscapes across the continent.

    “Fecal lipid biomarkers offer access to hitherto unknown (or at best, uncertain) information, adding to the growing body of evidence that is helping to build a picture of not only when and by what route people arrived but also how these people adapted to diverse landscapes across the continent (48–50).”
    Quote in the paperNot a substantial claim1 of 3 sources checked
    • cites [48] Waters M. R., Forman S. L., Jennings T. A., Nordt L. C., Driese S. G., Feinberg J. M., Keene J. L., Halligan J., Lindquist A., Pierson J., Hallmark C. T., Collins M. B., Wiederhold J. E., The Buttermilk Creek complex and the origins of Clovis at the Debra L. Friedkin site, Texas. Science 331, 1599– 1603 (2011). 21436451 source
    • cites [49] Halligan J. J., Waters M. R., Perrotti A., Owens I. J., Feinberg J. M., Bourne M. D., Fenerty B., Winsborough B., Carlson D., Fisher D. C., Stafford T. W. Jr., Dunbar J. S., Pre-Clovis occupation 14,550 years ago at the Page-Ladson site, Florida, and the peopling of the Americas. Sci. Adv. 2, e1600375 (2016). 27386553 PMC4928949 source

      The Introduction (page unavailable) dates the Page-Ladson occupation to about 14,550 years ago, and the Conclusions (page unavailable) describe how its occupants adapted to their environment. The paper therefore contributes evidence about when people were present and how they lived, but it does not establish an arrival route or show that fecal lipid biomarkers provide this information; its dung-related proxy is fungal spores. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [50] Goebel T., Waters M. R., O'Rourke D. H., The late Pleistocene dispersal of modern humans in the Americas. Science 319, 1497– 1502 (2008). 18339930 source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Consumption of carnivore meat can be hazardous to human health due to parasitic infections and the bioaccumulation of toxins.

    “Moreover, not only carnivores have a lower biomass transfer efficiency but also consumption of carnivore meat can be hazardous to human health due to parasitic infections and the bioaccumulation of toxins (35–37).”
    Quote in the paperNot a substantial claim3 of 3 sources checked
    • cites [35] McGrew A. K., Ballweber L. R., Moses S. K., Stricker C. A., Beckmen K. B., Salman M. D., O’Hara T. M., Mercury in gray wolves (Canis lupus) in Alaska: Increased exposure through consumption of marine prey. Sci. Total Environ. 468-469, 609– 613 (2014). 24056451 PMC3870183 source

      The Introduction (page unavailable) says mercury bioaccumulates in organisms, and the Conclusion (page unavailable) identifies possible harmful effects of mercury exposure in Alaskan wolves. This supports the toxin-bioaccumulation concern, but the paper does not establish that eating carnivore meat is hazardous to humans or that it causes parasitic infections. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [36] Schurer J. M., Pawlik M., Huber A., Elkin B., Cluff H. D., Pongracz J. D., Gesy K., Wagner B., Dixon B., Merks H., Bal M. S., Jenkins E. J., Intestinal parasites of gray wolves (Canis lupus) in northern and western Canada. Can. J. Zool. 94, 643– 650 (2016). source

      The discussion (draft p. 13) reports zoonotic parasites in wolves and identifies potential risks to human health. It does not say that eating carnivore meat transmits those parasites or address toxin bioaccumulation. The parasitic-health-risk portion is supported, but the claimed consumption route and toxin hazard are not. (LLM, conf=0.85)

      Experimental — accuracy not yet measured
    • cites [37] Moleon M., Martínez-Carrasco C., Muellerklein O. C., Getz W. M., Muñoz-Lozano C., Sánchez-Zapata J. A., Carnivore carcasses are avoided by carnivores. J. Anim. Ecol. 86, 1179– 1191 (2017). 28609555 source

      The Conclusions (page unavailable) report lower biomass redistribution from carnivore carrion and a higher risk of parasite transmission when carnivores consume it. The paper does not establish that eating carnivore meat is hazardous to humans or attribute such a hazard to bioaccumulated toxins. (LLM, conf=0.88)

      Experimental — accuracy not yet measured

  • It may state two separate claims as one.

    Premisecitation

    mtDNA analyses rely upon amplification of ultratrace amounts of extant mtDNA using PCR, making the approach more sensitive and more susceptible to contamination.

    “mtDNA analyses rely upon amplification of ultratrace amounts of extant mtDNA using the PCR, thereby making such an approach not only more sensitive but also more susceptible to contamination (45).”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [45] Llamas B., Valverde G., Fehren-Schmitz L., Weyrich L. S., Cooper A., Haak W., From the field to the laboratory: Controlling DNA contamination in human ancient DNA research in the high-throughput sequencing era. Sci. Technol. Archaeol. Res. 3, 1– 14 (2017). source

      The brief technical overview says PCR was traditionally used to amplify specific DNA targets in ancient-DNA research, and the “Contaminating human DNA” section calls PCR amplification a potent source of contamination. The paper does not say that mtDNA analyses rely on PCR amplification of ultratrace amounts of extant mtDNA, or that this makes mtDNA analysis more sensitive and more susceptible to contamination. (LLM, conf=0.83)

      Experimental — accuracy not yet measured

  • It may state two separate claims as one.

    Interpretationreasoning

    Coprophagy in canids is well-recognized and could explain both the presence of carnivore-derived lipids and human mtDNA, but it is unlikely that humans were eating carnivores.

    “Coprophagy in canids is a well-recognized phenomenon (34) and could explain both the presence of carnivore-derived lipids and human mtDNA, but it is unlikely that humans were eating carnivores as suggested by Gilbert and coworkers (6).”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [34] Livingston T. R., Gipson P. S., Ballard W. B., Sanchez D. M., Krausman P. R., Scat removal: A source of bias in feces-related studies. Wildl. Soc. Bull. 33, 172– 178 (2005). source
    • cites [6] Pedersen M. W., Overballe-Petersen S., Ermini L., Sarkissian C. D., Haile J., Hellstrom M., Spens J., Thomsen P. F., Bohmann K., Cappellini E., Schnell I. B., Wales N. A., Carøe C., Campos P. F., Schmidt A. M. Z., Gilbert M. T. P., Hansen A. J., Orlando L., Willerslev E., Ancient and modern environmental DNA. Philos. Trans. R. Soc. Lond. B Biol. Sci. 370, 20130383 (2015). 25487334 PMC4275890 source

      The citation is attached to the statement that coprophagy in canids is well recognized. Searches of our copy for “coprophagy” and for dogs eating feces found no passage addressing that behavior; the closest material concerns fecal DNA analysis (References, entries 25–26). The later explanation involving lipids and human mtDNA is not specifically attributed to this citation. (LLM, conf=0.75)

      Experimental — accuracy not yet measured

  • It may state two separate claims as one.

    Findingcitation

    Comparative assessment of lipids from coprolite 283 and a sediment sample collected directly underneath the coprolite reveals distinctly different distributions, with sediments differentiated by a high level of n-alkanols (C14-C34) with an even-over-odd predominance, characteristic of an input from higher plants.

    “Comparative assessment of lipids derived from coprolite 283 and a sediment sample collected directly underneath the coprolite (table S2) reveal distinctly different distributions where sediments are differentiated by a high level of n-alkanols (C14-C34) with an even-over-odd predominance, characteristic of an input from higher plants (27).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [27] Eglinton G., Hamilton R. J., Leaf epicuticular waxes. Science 156, 1322– 1335 (1967). 4975474 source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Findingreasoning

    Two of the coprolites yielded inconclusive results, most likely arising from a mixture of environmentally derived lipids and low fecal lipid preservation.

    “Two of the coprolites yielded inconclusive results, most likely arising from a mixture of environmentally derived lipids and low fecal lipid preservation.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    Of the 18 coprolites identified as containing human mtDNA by Gilbert and coworkers, 10 are interpreted as human in origin, 6 are ascribed a carnivore origin, and a remaining coprolite is most likely of mixed human/carnivore origin.

    “Of the 18 coprolites identified as containing human mtDNA by Gilbert and coworkers, 10 are interpreted as human in origin, 6 are ascribed a carnivore origin, and a remaining coprolite is most likely of mixed (human/carnivore) origin.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Findingown data

    A single coprolite (195) reported to contain mtDNA from H. sapiens and Canis lupus/familiaris also yielded fecal biomarker distributions indicative of a mixed human/carnivore origin.

    “A single coprolite (195) reported to contain mtDNA from H. sapiens and Canis lupus/familiaris also yielded fecal biomarker distributions indicative of a mixed human/carnivore origin.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    Of the 13 agreeing coprolites, the majority indicate a human origin (both Homo sapiens mtDNA haplogroups A and B) and range in age from 1308 ± 28 to 12,260 ± 60 14C yr B.P.

    “Of these, the majority indicate a human origin (both Homo sapiens mtDNA haplogroups A and B) and range in age from 1308 ± 28 to 12,260 ± 60 14C yr B.P.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    Of the remaining eight coprolites, two did not yield enough lipid to be viable for biomarker analysis.

    “Of the remaining eight coprolites, two did not yield enough lipid to be viable for biomarker analysis.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    Lipids, and hence fecal biomarkers, are chemically stable and, although some microbial or diagenetic alterations occur with time, the resulting structures can be linked back to their original source.

    “Lipids (and hence fecal biomarkers) are chemically stable and, although some microbial or diagenetic alterations do occur with time, the resulting structures can be linked back to their original source (29).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [29] Eglinton G., Logan G. A., Ambler R. P., Boon J. J., Perizonius W. R. K., Molecular preservation [and Discussion]. Philos. Trans. R. Soc. B 333, 315– 328 (1991). 1684047 source

  • It may state two separate claims as one.

    Premisenone given

    5β-stanols and bile acids have a substantial advantage over DNA in that they are hydrophobic and therefore unlikely to move within the stratigraphy of a sedimentary profile, highly recalcitrant within a sedimentary context over archaeological time scales, and highly diagnostic of fecal material and its producer organism(s).

    “Critically, 5β-stanols and bile acids have a substantial advantage over DNA in that they are (i) hydrophobic and therefore unlikely to move within the stratigraphy of a sedimentary profile, (ii) highly recalcitrant (far more so than DNA) within a sedimentary context over archaeological time scales, and (iii) highly diagnostic of fecal material and its producer organism(s).”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim.

    Premisecitation

    People first settled the Americas before Clovis.

    “It is largely, but not entirely, accepted by the archaeological community that people first settled the Americas before Clovis (1–3)”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites [1] Wheat A., Survey of professional opinions regarding the peopling of the Americas. SAA Archaeol. Rec. 12, 10– 14 (2012).
    • cites [2] Braje T. J., Dillehay T. D., Erlandson J. M., Klein R. G., Rick T. C., Finding the first Americans. Science 358, 592– 594 (2017). 29097536 source
    • cites [3] Jenkins D. L., Davis L. G., Stafford T. W. Jr., Campos P. F., Hockett B., Jones G. T., Cummings L. S., Yost C., Connolly T. J., Yohe R. M. II, Gibbons S. C., Raghavan M., Rasmussen M., Paijmans J. L. A., Hofreiter M., Kemp B. M., Barta J. L., Monroe C., Gilbert M. T. P., Willerslev E., Clovis age Western Stemmed projectile points and human coprolites at the Paisley Caves. Science 337, 223– 228 (2012). 22798611 source

  • Probably not a substantial claim. The paper may give no reason why it holds. It may state two separate claims as one.

    Premisenone given

    Bulrush is one of the most common basketry fibers in the region; it is not natural to the cave deposits and is a cultural addition.

    “Bulrush is one of the most common basketry fibers in the region; it is not natural to the cave deposits and is a cultural addition.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationown data

    The lipid differences between coprolite 283 and the underlying sediment show that the lipids are representative of the matrix from which they are derived and have experienced minimal leaching or lateral movement within the sedimentary profile.

    “Crucially, this shows that the lipids are representative of the matrix from which they are derived and have experienced minimal leaching or lateral movement within the sedimentary profile.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    The findings from the coprolites from Paisley Caves have been the subject of criticism.

    “the findings from the coprolites from Paisley Caves have been the subject of criticism (7, 8).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites [7] Poinar H., Fiedel S., King C. E., Devault A. M., Bos K., Kuch M., Debruyne R., Comment on “DNA from pre-Clovis human coprolites in Oregon, North America”. Science 325, 148 (2009). 19589985 source
    • cites [8] Goldberg P., Berna F., Macphail R. I., Comment on “DNA from pre-Clovis human coprolites in Oregon, North America”. Science 325, 148 (2009). 19589984 source

  • It may state two separate claims as one.

    Premisecitation

    Three coprolites identified as human were dated this way but showed agreement between the macroflora and solute dates.

    “Three coprolites identified as human were also dated this way but showed an agreement between the macroflora and solute dates.”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [3] Jenkins D. L., Davis L. G., Stafford T. W. Jr., Campos P. F., Hockett B., Jones G. T., Cummings L. S., Yost C., Connolly T. J., Yohe R. M. II, Gibbons S. C., Raghavan M., Rasmussen M., Paijmans J. L. A., Hofreiter M., Kemp B. M., Barta J. L., Monroe C., Gilbert M. T. P., Willerslev E., Clovis age Western Stemmed projectile points and human coprolites at the Paisley Caves. Science 337, 223– 228 (2012). 22798611 source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisereasoning

    Because PCR amplifies vanishingly low amounts of DNA, such analyses are particularly prone to contamination.

    “Because the polymerase chain reaction (PCR) method amplifies vanishingly low amounts of DNA, such analyses are particularly prone to contamination.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationown data

    The bulrush artifact date confirms the pre-Clovis age and stratigraphic integrity of the deposit.

    “confirming the pre-Clovis age and stratigraphic integrity of the deposit.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Premisecitation

    Sites such as Coopers Ferry, Idaho and Paisley Caves, Oregon provide evidence that Western Stemmed Tradition technology predates Clovis, establishing it as the oldest well-defined technological tradition in North America, with links to late Pleistocene sites in East Asia and Siberia.

    “Sites like Coopers Ferry, Idaho and Paisley Caves, Oregon provide evidence that WST technology predates Clovis, establishing this as the oldest well-defined technological tradition in North America, with links to late Pleistocene sites in East Asia and Siberia (3, 4).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [3] Jenkins D. L., Davis L. G., Stafford T. W. Jr., Campos P. F., Hockett B., Jones G. T., Cummings L. S., Yost C., Connolly T. J., Yohe R. M. II, Gibbons S. C., Raghavan M., Rasmussen M., Paijmans J. L. A., Hofreiter M., Kemp B. M., Barta J. L., Monroe C., Gilbert M. T. P., Willerslev E., Clovis age Western Stemmed projectile points and human coprolites at the Paisley Caves. Science 337, 223– 228 (2012). 22798611 source
    • cites [4] Davis L. G., Madsen D. B., Becerra-Valdivia L., Higham T., Sisson D. A., Skinner S. M., Stueber D., Nyers A. J., Keen-Zebert A., Neudorf C., Cheyney M., Izuho M., Iizuka F., Burns S. R., Epps C. W., Willis S. C., Buvit I., Late Upper Paleolithic occupation at Cooper’s Ferry, Idaho, USA, ~16,000 years ago. Science 365, 891– 897 (2019). 31467216 source

  • It may state two separate claims as one.

    Premisecitation

    5β-stanols and bile acids are two lipid compound classes already well established as fecal biomarkers.

    “5β-stanols and bile acids are two lipid compound classes already well established as fecal biomarkers [see (12, 13) and references therein].”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites [12] Bull I. D., Lockheart M. J., Elhmmali M. M., Roberts D. J., Evershed R. P., The origin of faeces by means of biomarker detection. Environ. Int. 27, 647– 654 (2002). 11934114 source
    • cites [13] Prost K., Birk J. J., Lehndorff E., Gerlach R., Amelung W., Steroid biomarkers revisited - improved source identification of faecal remains in archaeological soil material. PLOS ONE 12, e0164882 (2017). 28060808 PMC5217961 source

      Checked before — its earlier verdict is held back until a new check runs.

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Premisecitation

    Lipid biomarkers are chemically stable, existing in rocks dating to 1.6 billion years.

    “They are also chemically stable, with lipid biomarkers existing in rocks dating to 1.6 billion years (21), far greater than more recent archaeological time scales”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [21] Brocks J. J., Love G. D., Summons R. E., Knoll A. H., Logan G. A., Bowden S. A., Biomarker evidence for green and purple sulphur bacteria in a stratified Palaeoproterozoic sea. Nature 437, 866– 870 (2005). 16208367 source

  • It may state two separate claims as one.

    Premisecitation

    Human feces are usually characterized by high levels of coprostanol and higher amounts of deoxycholic acid and lithocholic acid.

    “Conversely, human feces are usually characterized by high levels of coprostanol and higher amounts of deoxycholic acid and lithocholic acid (43).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [43] Elhmmali M. M., Roberts D. J., Evershed R. P., Bile acids as a new class of sewage pollution indicator. Environ. Sci. Technol. 31, 3663– 3668 (1997). source

  • It may state two separate claims as one.

    Premisecitation

    Sterols derived from canid feces are characterized by very high levels of cholesterol and only trace amounts, if any, of cholesterol-derived 5β-stanols (coprostanol and epicoprostanol) because canids lack the gut microbiota responsible for producing these compounds.

    “Sterols derived from canid feces are characterized by very high levels of cholesterol, and only trace amounts (if any) of cholesterol-derived 5β-stanols (coprostanol and epicoprostanol) as canids lack the gut microbiota responsible for producing these compounds (38).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [38] Leeming R., Ball A., Ashbolt N., Nichols P., Using faecal sterols from humans and animals to distinguish faecal pollution in receiving waters. Water Res. 30, 2893– 2900 (1996). source

  • It may state two separate claims as one.

    Interpretationcitation

    Little to no cholesterol-to-coprostanol conversion may result in false negatives when differentiating human coprolites from carnivores and may explain the lack of agreement between mtDNA and fecal biomarker results in six coprolites.

    “This may potentially result in false negatives when differentiating human coprolites from carnivores and may explain the lack of agreement between mtDNA and fecal biomarker results in these six coprolites.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Interpretationreasoning

    Coprophagy of human feces by carnivores is one explanation for the mixed human/carnivore result in coprolite 195.

    “One explanation for these results from a single specimen is coprophagy of human feces by carnivores.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. It may state two separate claims as one.

    Study design and conductnone given

    Several coprolites are associated with the same catalog number, and we cannot be 100% certain that we analyzed the same coprolite that was analyzed for mtDNA.

    “Several coprolites are associated with the same catalog number, and we cannot be 100% certain that we analyzed the same coprolite that was analyzed for mtDNA.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationreasoning

    Coprolites 283 and 185 are from the oldest deposits in the cave, so lower recovery of lipid is not unexpected.

    “At 12,125 ± 30 14C yr B.P. (283) and 12,345 ± 55 14C yr B.P. (185), these both represent coprolites from the oldest deposits in the cave and a lower recovery of lipid is therefore not unexpected.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Premisecitation

    Fecal biomarker analyses rely upon coprolites containing enough of each compound to enable detection and quantification, typically in the region of >0.4 μg g−1 coprolite, with the concentration of compounds remaining a direct reflection of age and depositional environment.

    “Conversely, fecal biomarker analyses are reliant upon coprolites containing enough of each compound to enable detection and quantification (typically in the region of >0.4 μg g−1coprolite), with the concentration of compounds remaining being a direct reflection of age and depositional environment (30–33).”
    Quote in the paperNot a substantial claim0 of 4 sources checked
    • cites [30] Nishimura M., Koyama T., The occurrence of stanols in various living organisms and the behavior of sterols in contemporary sediments. Geochim. Cosmochim. Acta 41, 379– 385 (1977). source
    • cites [31] Hatcher P. G., McGillivary P. A., Sewage contamination in the New York Bight. Coprostanol as an indicator. Environ. Sci. Technol. 13, 1225– 1229 (1979). source
    • cites [32] McCalley D. V., Cooke M., Nickless G., Coprostanol in Severn Estuary sediments. Bull. Environ. Contam. Toxicol. 25, 374– 381 (1980). 6775719 source
    • cites [33] Bartlett P. D., Degradation of coprostanol in an experimental system. Mar. Pollut. Bull. 18, 27– 29 (1987). source

  • It may state two separate claims as one.

    Interpretationreasoning

    Fecal biomarker analysis lacks the detailed information that mtDNA may provide but delivers a more rapid assessment of coprolites and can provide robust supporting evidence where mtDNA-based results are open to criticism.

    “While fecal biomarker analysis lacks the detailed information that mtDNA may provide, it does deliver a more rapid assessment of coprolites that, as in this study, can provide robust supporting evidence where results obtained by mtDNA-based approaches are open to criticism.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim.

    Premisecitation

    About a quarter of North American subjects in a study exhibited little to no conversion of cholesterol to coprostanol.

    “Previous work has reported that about a quarter of North American subjects in a study exhibited little to no conversion of cholesterol to coprostanol (44).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [44] Wilkins T. D., Hackman A. S., Two patterns of neutral steroid conversion in the feces of normal north americans. Cancer Res. 34, 2550– 2554 (1974). 4843533
34 of 34

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. A. Wheat, Survey of professional opinions regarding the peopling of the Americas. SAA Archaeol. Rec. 12, 10–14 (2012).
  2. R. P. Evershed P. H. Bethell in Archaeological Chemsitry Organic Inorganic and Biochemical Analysis M. V. Orna Ed. ACS Symposium Series 625 Chapter 13 (American Chemical Society Washington DC USA 1996) 459 p.

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Related

Metadata

Authors
Shillito, L.-M., Whelton, H. L., Blong, J. C., Jenkins, D. L., Connolly, T. J., & Bull, I. D.
Affiliations
  • Newcastle University (GB)
  • University of Bristol (GB)
  • University of Oregon (US)
Corresponding author
  • Shillito, Lisa-Marie
  • Bull, Ian D.
ORCID
Venue
Science Advances
Publisher
American Association for the Advancement of Science (AAAS)
Published
2020-07-17
Volume
6
Issue
29
Pages
eaba6404-eaba6404
ISSN
2375-2548 (ISSN-L)
DOI
10.1126/sciadv.aba6404
PMC
PMC7363456
OpenAlex
W3035091798
Cited by
91
References
49
Citations by year
2026: 13 · 2025: 9 · 2024: 10 · 2023: 14 · 2022: 17 · 2021: 25 · 2020: 3
FWCI
31.71
Type
journal article
Language
en
Open access
Licence
Locations
  • Science Advances (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • Explore Bristol Research (publishedVersion, cc-by)
  • Bristol Research (University of Bristol) (submittedVersion, cc-by)
  • Digital Commons - University of South Florida (University of South Florida) (submittedVersion)
  • Newcastle University ePrints (Newcastle Univesity) (cc-by)
Funders
Natural Environment Research Council (NE/P003001/1)
Topics
  • Social Sciences › Anthropology › Pleistocene-Era Hominins and Archaeology
  • Social Sciences › Archeology › Archaeology and ancient environmental studies
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Forensic and Genetic Research
Keywords
coprolites

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-11-08, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-11-08 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Cited sources are checked with a language model’s help (gpt-6-sol).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

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