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Prof John Morgan  -  PhD, DSc

Eisenia fetida

Figure 1: A close encounter between a nosey biologist and his subject (Eisenia fetida).

John is a Reader in the School. His initial interest in gerontology and, specifically, in the physiosclerosis of ageing mammalian soft-tissues led to a commitment to electron probe X-ray microanalysis (EPXMA) and associated cryopreparative procedures. This work helped project the Cardiff Laboratory, directed at the time by Professor David Erasmus, to the forefront of low-temperature analytical microscopy, and led to a period of secondment for John as acting Director of Electron Microscopy at the University of Oslo. A desire to exploit the high resolution capabilities of EPXMA to enhance understanding of the cellular physiology of biomineralization led to the exploration of the earthworm calciferous gland as a model system. Earthworms continue to be the main focus of John’s research effort (Figure 1), but the approach to their biology has diversified. Terrestrial ecotoxicology is the dominant current research theme.


Figure 2: Immuno-peroxidase localisation of the cadmium-binding protein, metallothionein, in the urine-forming nephridia of an earthworm (Lumbricus rubellus).

John is part of an active cluster of staff (notably including Drs Peter Kille and Stephen Stürzenbaum) and postgraduates at Cardiff who, with collaborators at universities and research institutes in the UK and beyond, have integrated their complimentary skills to study in depth aspects of the metal/metalloid relationships of earthworms, ranging from the genetic, through the cellular, to the ecological levels of biological organisation. Molecular genetic, biochemical, microscopical imaging and analysis, as well as demographic modelling techniques are deployed by members of this productive partnership. John’s particular aptitude, however, is toward the cellular (Figures 2) and higher organisational levels. One aim of these studies is to combine fundamental and applied knowledge to provide the user community with novel, sensitive, robust, and relevant contaminated-land biomonitoring tools. Another aim is to compile a comprehensive set of Expressed Sequence Tag (EST) genetic libraries for a sentinel earthworm species (Lumbricus rubellus) to facilitate an understanding of the mechanistic bases of the responses of the animal to potentially toxic inorganic and organic environmental contaminants. This ongoing effort is developing into an invaluable resource in the form of the publicly-accessible LumbriBASE (, currently containing c.20,000 sequences representing c.8,000 genes, approximately 40% of which have been sequenced. Quantitative PCR is routinely used to measure the expression of individual genes, including metallothioneins and heat shock proteins; DNA microarrays have been successfully used to quantify the trancriptomic profiles of earthworms exposed to different doses of Cd, Cu, fluoranthene, and atrazine.

Quantitative X-ray distribution maps

Figure 3: Quantitative X-ray distribution maps showing how metals are compartmentalised in the liver-like chloragocyte cells of an earthworm (Dendrodrilus rubidus) living in a mine associated soil heavily polluted with Cd, Pb, and Zn. Sample preparation: hyperbaric freezing; freeze-substitution; thin sectioning; no staining.

Differences in the degree of pigmentation of the earthworm, Lumbricus rubellus.

Figure 4: Inter-population differences in the degree of pigmentation of the earthworm, Lumbricus rubellus. The pale worms were sampled from heavily contaminated, calcareous, Pb/Zn mine soils. Are these striking colour differences determined primarily by genotypic or site-specific environmental factors?

In parallel with the molecular genetic activities, John is currently engaged in the use of physical techniques, including EPXMA, electron spin resonance spectroscopy, and high-energy synchrotron sources (EXAFS and XANES), for determining the sub-cellular compartmentation (Figure 3) and ligand-binding speciation of metals in earthworms living in metalliferous soils. Moreover, Fourier Transform Infra-Red (FTIR) microspectroscopy at the Daresbury synchrotron and H1-NMR metabolomic profiling have been optimised to describe the biochemical perturbations caused by the accumulated metals. A project is also underway to use highly discriminatory genetic techniques, such as microsatellite analysis (- Professor Mike Bruford and Dr. Georgina Harper have already identified the requisite number of promising microsatellites in our favoured earthworm species -) to study gene flow and genetic differentiation in earthworm populations that have already been shown to display some striking phenotypic differences (Figure 4).>/p>

Journal cover "Earthworms Nature's gardeners

Figure 5: A close encounter between a biologist and a wider readership.

The suite of genotyping tools at the disposal of the team have already shown that L. rubellus comprises of two major genetic lineages with a genetic divergence (~12%) normally considered to correspond to inter-species divergence. Gene sequencing indicates that Pb resistance in earthworm populations with multi-generational field histories of exposure to the metal is phenotypically associated with adjustments in Ca cellular physiology. Thus, major inroads are being made into the understanding at a molecular level of microevolutionary aspects of the adaptation of field populations to inorganic stressors. In the near future it is intended to extend these studies to make it possible to use the earthworm as an accessible metazoan laboratory model for studying the disruptive effects of environmental toxins on fundamental processes, such as haem synthesis, wound healing and tissue regeneration.

Finally, John contributes actively in research-led teaching at Cardiff University (- he is currently the Zoology Scheme coordinator -), and he is an enthusiastic promoter of the public understanding of science ( ; Figure 5).

Current Research Interests
  1. Sub-cellular compartmentation and speciation of metals in terrestrial invertebrates.
  2. Biomarkers of stress: cellular, molecular genetic, and physicochemical assays.
  3. Micro-evolution: genetic and phenotypic bases of metal resistance mechanisms in field populations of earthworms with multi-generational histories of exposure.

Current Active Research Collaborators


Dr. P. Kille (BIOSI); Prof. M.W. Bruford (BIOSI); Dr. M.S. Davies (BIOSI); Dr. C. Muller (BIOSI); Dr. A. King (BIOSI); Prof. K. Williams & Prof. A. Griffiths (ENGIN); Dr. D. Murphy (CHEMY); Mr. P. Fisher (EARTH); Dr. G. Harper (University of Glamorgan).


Dr. S.R. Stürzenbaum (King’s, London); Drs. D. Spurgeon & C. Svendsen (CEH, Monks Wood); Dr. J. Bundy (Imperial); Prof. M. Blaxter (Edinburgh); Drs. M. Hodson (Reading); Drs. J.Charnock, A. Bennett,  and F. Bahrami (CCLRC, Daresbury); Dr. F. Mosselmans (‘Diamond’, Rutherford-Appleton Laboratory); Dr. J. Cotter-Howells (Exeter); Dr. P. Brophy (Liverpool);  Drs. T.G. Piearce, C. Langdon & K. Semple (Lancaster); Dr. S. Lofts (CEH, Lancaster); Prof. R. Blackshaw (Plymouth); Dr. David Marshall (The Bulmer Foundation).


Prof. B. Plytycz & Dr. A. Rozen (Kracow, Poland); Prof. M. Soto (Bilbao, Basque Country); Prof. Ionan Marigomez (Bilbao, Basque Country); Dr. L. Mólnar (Pécs, Hungary); Drs. F. Marińo & M. Briones (Vigo, Spain); Dr. N.A. Azwady (Selangor, Malaysia); Dr. M. Jonker (Amsterdam, The Netherlands); Dr. J. Nahmani (CNRS, Metz, France); Prof. F. Vandenbulcke (Lille, France); Dr. S. Sletner Klemsdal (Norwegian Institute of Agricultural and Environmental Research, Norway); Prof. S. Gamou (Tokyo, Japan); Dr. T. Anderson (Texas Tech University, USA).

Memberships and Affiliations

  • Member, Society of Environmental Toxicology and Chemistry (SETAC)
  • Member, SETAC (International) Soil Advisory Group
  • Member, Synchrotron Radiation (SR) User Forum, under the auspices of the Science and Technology Facilities Council (STFC), 2007-
  • Member, NERC Depleted Uranium Programme Panel, 2004
  • Fellow, Royal Microscopical Society
  • Associate Editor (Microanalysis), Journal of Microscopy, 1988-1992
  • Member, British Society of Soil Science (and of its ‘Earthworm’ special interest group)
  • Millennium Awards Fellow, 2000 (supported by the Royal Society)
  • International Advisor, 8th International Symposium on Earthworm Ecology, Krakow 2006
  • International Advisor, 9h International Symposium on Earthworm Ecology, Mexico, 2010
  • Member of the Scientific Committee of the Cardiff National Eisteddfod (2008)
  • Consultant for the Welsh Assembly Government on its Environmental Strategy for Wales.

Recent Invited Contributions

  • Organiser and Committee Chairman, 7th International Symposium on Earthworm Ecology, Cardiff 2002   -
  • Reviewer (Professorial Research Outputs), NRF, South Africa, 2006
  • Reviewer (Professorial Research Outputs),NRF,South Africa, 2007
  • Visiting Professor  (Ph.D. level taught course in Electron Microscopy and Ecotoxicology), University of Bilbao, Spain, July 2005
  • Visiting Professor, Jagellonian University, Krakow, Poland, 2004
  • Visiting Lecturer, University of Bauchi, Northern Nigeria, 1996
  • Visiting Lecturer, University of Los Baños, The Philippines, 1990 & 1992
  • Visiting Lecturer, University of Bangalore, India, 1992
  • External Validator (x3 Life Sciences M. Res. Schemes), University of Plymouth 2005
  • Internal Validator (M.Sc. Hydrogeology), EARTH, Cardiff University, 2005
  • External Validator (Life Sciences), University College Worcester, 2002
  • External Examiner (Ph.D.): Newcastle, Manchester, Reading (x2), Lancaster, Oslo
  • External Examiner (D.Sc.): University of Wales
  • External Examiner (Readership):University of London
  • External Examiner (Life Sciences Schemes), University College Worcester, 2006-2009
  • Organiser, British Biological X-ray Microanalysis Group Meeting, Cardiff, 1996
  • Visiting Lecturer (Environmental Toxicology Postgraduate Workshops), University of Oslo, 1984-1994
  • Appointments Committee (International Advisor), Director of Electron Microscopy, Univ. of Oslo, 1986
  • UK Secretary and contributor: Indo-UK Workshop on Vermitechnology, India, 2008. 
  • Invited Speaker, ‘Microscopy for the New Millennium’, Cardiff, September 2007.
  • Chairman and Plenary Speaker, 8th Int. Symp. Earthworm Ecol., Krakow, Poland, 2006
  • Invited Speaker, Univ. of Aberdeen, Nov. 2005; Jagiellonian Univ., March 2006
  • Invited Speaker, 35th Anniversary Meeting of the SEMT,Milton Keynes, April 2005
  • Chairman and Keynote Speaker, 3rd Int. Workshop Earthworm Ecotoxicology, Åarhus, Denmar, 2001
  • Chairman and Keynote Speaker, 6th Int. Symp. on Earthworm Ecol., Vigo, Spain, 1998
  • Chairman and Keynote Speaker, 5th Int. Symp. on Earthworm Ecol.,  Ohio, 1994
  • Chairman and Keynote Speaker, 4th Int. Symp. on Earthworm Ecol., France, 1990
  • Reviewer for, amongst others, the journals: Environmental Science & Technology; Environmental Toxicology and Chemistry; Ecotoxicology and Environmental Safety; Environmental Pollution; Applied Soil Ecology; Soil Biology & Biochemistry; Pedobiologia; European Journal of Soil Biology.