Species → Common Earthworm
Common Earthworm
Lumbricus terrestris
What if it disappeared?
Impact ModerateWithout earthworms structuring the soil through their burrows, soil would lose the better drainage, better aeration, and faster organic-matter decomposition this role provides — documented since Darwin's original work, confirmed since by hundreds of field studies.
DocumentedDetail
Darwin, C. (1881). The Formation of Vegetable Mould, through the Action of Worms, with Observations on their Habits. John Murray.
Darwin was the first to document, over decades of observation, how earthworms turn over and enrich topsoil. The 2019 global compilation confirms and quantifies this role at scale: earthworms are a major determinant of the structure and fertility of temperate soils.
The disappearance of earthworms in intensively farmed soils is associated with reduced fertility and water-holding capacity — but isolating the earthworm's share from that of other farming practices in this loss remains difficult.
ExtrapolatedDetail
Phillips, H.R.P., Guerra, C.A., Bartz, M.L.C. et al. (2019). Global distribution of earthworm diversity. Science, 366(6464), 480–485.
This compilation of data from 6,928 sites in 57 countries establishes the global patterns of earthworm abundance and diversity, and identifies climate as a stronger determinant than soil properties themselves — a landmark mapping effort, not a direct measurement of fertility loss.
What's missing to confirm it: How much of the agricultural soil fertility loss is directly attributable to declining earthworm populations, rather than to the practices (deep tillage, pesticides) that cause both at once, isn't isolated by the available studies.
Documentation
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The Effect of Earthworm (Lumbricus terrestris) Population Density and Soil Water Content Interactions on N2O Emissions — Applied and Environmental Soil Science
Accessed August 10, 2026
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Phillips et al. (2019) — Global distribution of earthworm diversity, Science
Accessed August 7, 2026
Last verified: August 14, 2026