Action of earthworms on flint burial - a return to Darwin's estate


For thirty years, from the early 1840s, Charles Darwin documented the disappearance of flints in the grounds of Down House in Kent, at a location originally known as the “Stony Field”. This site (Great Pucklands Meadow – GPM) was visited in 2007 and an experiment set up in this ungrazed grassland. Locally-sourced flints (either large – 12 cm, or small – 5 cm dia.) were deposited at two densities within sixteen 1 m2 plots in a randomised factorial design. The area selected was distant from public access routes and remained unmown throughout the duration here reported. Fixed point photographs were taken at the outset to enable later photogrammetric analysis. After 6 years, the site was re-examined. The flints had generally been incorporated into the soil. Photographs were re-taken, proportion of buried flints recorded and measurements made of burial depth from a quarter of each plot. Results showed that large flints were more deeply incorporated than smaller (p = 0.025), but more of the latter were below the soil surface. A controlled laboratory experiment was also conducted using Aporrectodea longa (the dominant earthworm species in GPM) to assess effects of casting in the absence of other biota. Results suggested that this species has a major influence on flint burial through surface casting. Combined with a long term, but small scale collection of A. longa casts from an area close to GPM, all results were consistent with those provided by Darwin and showed that rate of flint burial was within the range of 0.21–0.96 cm y-1.

  • Citation: Butt, Kevin R.; Callaham Jr., Mac A.; Loudermilk, E. Louise; Blaik, Rowan 2016. Action of earthworms on flint burial - a return to Darwin's estate. Applied Soil Ecology, Vol. 104: 6 pages.: 157-162. DOI:10.1016/j.apsoil.2015.04.002
  • Keywords: Bioturbation, Charles Darwin,Casting, Down House, Soil
  • Posted Date: September 14, 2016
  • Modified Date: October 5, 2016
  • Print Publications Are No Longer Available

    In an ongoing effort to be fiscally responsible, the Southern Research Station (SRS) will no longer produce and distribute hard copies of our publications. Many SRS publications are available at cost via the Government Printing Office (GPO). Electronic versions of publications may be downloaded, printed, and distributed.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.