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Cited by 471Marine animal studies overviewMarine Plankton and BiogeochemistryAnimal Ecology and Behavior Studies

The DOI matches its Crossref record; 82 of the 82 references it cites were found in a registry or an index; none of the 50 sources its claims cite is checked for support yet.

Global nutrient transport in a world of giants

Open access
Doughty, Christopher E., Roman, Joe, Faurby, Søren, Wolf, Adam, Haque, Alifa, Bakker, Elisabeth S., Malhi, Yadvinder, Dunning, John B., Svenning, Jens-Christian·2016·Proceedings of the National Academy of Sciences
DOI 10.1073/pnas.1502549112PMC PMC4743783
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Abstract

Significance: Animals play an important role in the transport of nutrients, but this role has diminished because many of the largest animals have gone extinct or experienced massive population declines. Here, we quantify the movement of nutrients by animals in the land, sea, rivers, and air both now and prior to their widespread reductions. The capacity to move nutrients away from hotspots decreased to 6% of past values across land and ocean. The vertical movement of phosphorus (P) by marine mammals was reduced by 77% and movement of P from sea to land by seabirds and anadromous fish was reduced by 96%, effectively disrupting an efficient nutrient distribution pump that once existed from the deep sea to the continental interiors.

Overview

Integrity signals

Registry

Crossref · 10.1073/pnas.1502549112

Cites

82 of 82 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

0 of 50 cited sources checked · 0 supported · 0 flagged

Show all 59 claims

  • It may state two separate claims as one. 26
  • Probably not a substantial claim. 5
27 of 27

  • The authors state this as an assumption.

    No previous study has attempted a global-scale estimate of how nutrient distribution changed from before human-caused extinctions and exploitation to today across oceans, air, rivers, and land.

    “There have been many individual site-level studies showing the importance of animals in distributing nutrients, but as far as we are aware, no previous study has attempted to estimate at a global scale how this distribution has changed from the time before humancaused extinctions and exploitation up to today in the oceans, air, rivers, and land.”

  • The paper relies on this without support.

    Phosphorus serves as a proxy for other limiting elements such as nitrogen and iron.

    “We calculate nutrient fluxes caused by animals in terms of the frequently limiting nutrient, P, which serves as a proxy for other limiting elements, such as N and Fe.”

  • The authors state this as an assumption.

    20% of seabird guano produced reaches coastal land, with a range of 5% to 35%.

    “assume 20% (5 to 35%) of guano reaches land”
    “We assume that 20% (ranging between 5% and 35%) of seabird guano produced arrives on coastal land.”

  • The authors state this as an assumption.

    Seabird population calculations are representative of past, not current, populations because they are based on theoretical population densities.

    “We assume our calculations for seabird populations are representative of past, not current, populations because they are based on theoretical population densities (43).”

  • The paper relies on this without support.

    Guano is generally deposited on steep cliffs or offshore islands that are largely inaccessible to most terrestrial animals.

    “Guano is generally deposited on steep cliffs or offshore islands generally inaccessible to most terrestrial animals.”

  • The paper relies on this without support.

    Most seabird islands are on continental shelves that become connected to continents during interglacial periods.

    “For instance, most seabird islands are on the continental shelves, which become connected to the continent during interglacial periods, thus exposing the nutrient hotspots to terrestrial animals.”

  • The paper relies on this without support.

    Most domestic animals in the industrialized world are fenced in or indoors, and fences constrain movement.

    “First, most domestic animals in the industrialized world are fenced in (or indoors), and fences constrain movement, thus stopping the diffusion of nutrients (fences are less common in the nonindustrialized world, although the animals may be fenced in at night).”

  • The paper relies on this without support.

    Most pastures contain only a single animal type, such as cattle.

    “Second, most pastures have only a single animal type, such as cattle.”

  • The paper relies on this without support.

    A single species is more likely to have consistent behavior, eating in one place and defecating in another, concentrating nutrients rather than dispersing them.

    “A single species is more likely to have consistent behavior, eating in one place, defecating in another, and concentrating nutrients instead of dispersing them across gradients.”

  • The paper relies on this without support.

    Multiple species have different eating and defecating patterns and are more likely to diffuse nutrients across gradients.

    “By contrast, multiple species have different eating and defecating patterns and are more likely to diffuse nutrients across gradients.”

  • The paper relies on this without support.

    Aquatic algae conduct most of the ocean's photosynthesis and have a much faster turnover time than land plants due to their often single-cellular nature.

    “Aquatic algae, which conduct most of the ocean ' s photosynthesis, have a much faster turnover time than land plants due to their often single-cellular nature”

  • The authors state this as an assumption.

    Twenty percent of guano arrives on land.

    “assuming 20% of the guano arrives on land”
12 of 12

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Africa's reported percentage does not match the table values

    Minor

    Table 1 gives Africa a current capacity of 6.67e4 and a past capacity of 1.28e5. Dividing current by past gives 52.1%, not the reported 46%.

    Reported 46 · recomputed 52.109375

  • South America was not the highest-capacity continent in the table

    Minor

    The discussion says South America had the largest past nutrient distribution capacity, but Table 1 lists 1.53e5 for South America and a higher value, 2.77e5, for Eurasia.

  • The fish phosphorus flux is given diffusivity units

    Minor

    The results attach km2 per year to the historical 140-million phosphorus flux from anadromous fish. Table 1 gives that same quantity in kg P per year.

  • The seabird total is assigned a per-area unit

    Minor

    The results describe the 6.3-million seabird flux in kg per square kilometer per year, whereas Table 1 presents the same figure as a total in kg P per year.

4 of 4

Citations

Cites

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Show all 82 references

Research works printed but not linked: 2

  1. 10.1093/acprof:osobl/9780199735693.001.0001 · DOI · Paper page
  2. T Tyrberg, The Late Pleistocene continental avian extinction—An evaluation of the fossil evidence. Oryctos 7, 249–269 (2008).

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Metadata

Authors
Doughty, C. E., Roman, J., Faurby, S., Wolf, A., Haque, A., Bakker, E. S., Malhi, Y., Dunning, J. B., & Svenning, J.-C.
Affiliations
  • University of Oxford (GB)
  • University of Vermont (US)
  • Aarhus University (DK)
  • Princeton University (US)
  • Netherlands Institute of Ecology (NL)
  • Purdue University West Lafayette (US)
ORCID
Venue
Proceedings of the National Academy of Sciences
Publisher
National Academy of Sciences
Published
2015-10-26
Volume
113
Issue
4
Pages
868-873
ISSN
  • 0027-8424 (ISSN-L)
  • 1091-6490
DOI
10.1073/pnas.1502549112
PMC
PMC4743783
OpenAlex
W1826044145
Semantic Scholar
73ec212cf94b82ed41724cc153e72b1e98c69f2b
Cited by
470
References
82
Citations by year
2026: 27 · 2025: 46 · 2024: 50 · 2023: 63 · 2022: 46 · 2021: 49 · 2020: 63 · 2019: 47 · 2018: 26 · 2017: 32 · 2016: 17 · 2015: 3
FWCI
23.57
Type
journal article
Language
en
Open access
Locations
  • Proceedings of the National Academy of Sciences (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • KNAW Research Portal (The Royal Netherlands Academy of Arts and Sciences) (publishedVersion, other-oa)
  • Data Archiving and Networked Services (DANS) (submittedVersion, other-oa)
Funders
Danmarks Grundforskningsfond
Topics
  • Physical Sciences › Environmental Science › Ecology › Marine animal studies overview
  • Physical Sciences › Earth and Planetary Sciences › Oceanography › Marine Plankton and Biogeochemistry
  • Physical Sciences › Environmental Science › Ecology › Animal Ecology and Behavior Studies
Keywords
nutrient cycling, megafaunal extinction, marine mammals, whales, seabirds, anadromous fish, phosphorus, nutrient transport, nutrient hotspots, large animals
MeSH terms
Animals, Behavior, Animal, Birds, Diffusion, Feeding Behavior, Fishes, Food, Food Supply, Homing Behavior, Mammals, Oceans and Seas, Population Density, Ecosystem, Body Size, History, Ancient, Extinction, Biological, Aquatic Organisms, Animal Distribution

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