Entomobrya multifasciata . A common, boldly marked Collembole found on the soil surface in a wide range of habitats. |
Peter Shaw's Collembola page
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Entomobrya atrocincta, from Tenerife. Collected by Brent Emerson (UEA) as part of population-level DNA sampling.
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These animals are wingless hexapods which have changed little since
the early colonisation of land over 400 million years BP. We know
this, because some obligingly became fossilised in agate by a silaceous
spring, laying down what are now the amazing Rhynie cherts (of Scotland).
These Collembola, Rhyniella praecursor, could (almost) have crawled
into one of my Tullgren extractors today. I carefully avoided calling
them insects, since despite their 6 legs and long-standing classification
as insects, these arthropods may well have evolved the hexapod state independently
of true insects. In particular they have a unique cephalic structure
(the post antennal organ) which may be the remains of the second antennae
of crustacea. DNA work (eg Regier et al 2010) has Collembola next to Diplura
as intermediate between the remipedia (crustacea) and true insecta. Probably the best current model has
has "hexapoda" as a valid clade that contains insects diplura and Collembola, but with a common ancestor that had more than 3 pairs of legs. This then gave us insects (which evolved wings) and Collembola (which retained legs as a jumping organ).
To rephrase into more accessible but less accurate terms,
if insects are the left page of a book and crustacea the right, Collembola fit snugly down the middle of the spine.
The UK database is now held here on the Roehampton server. The Irish records (which I picked up from Steve Hopkin but have passed on) are available here .
To study UK Collembola you should, still, study the resources on Steve Hopkin's page. Steve lectured at Reading university until his untimely death in a car crash in May 2006, and was previously invaluable in helping me name awkward (and common but mis-identified) specimens. I took a couple of year transferring the maps over so that I can ensure that they are kept updated as records come in.
Another useful resource is the world springtail page run by Frans Janssens.
Nico Van Straalen and his impressive team at the Vreij University Amsterdam (including Matty Berg, Jacintha Ellers, Dick Roelofs, Valentina Zizarri and colleagues) lead the world in Collembola research, and (quite apart from decades of top ecological research) can tell you the pollution level of soil by letting some springtails loose in it for a while then sequencing their Expressed Sequence Tags (ETS), to compare with baseline Folsomia candida transcriptome to look for patterns of stress gene activation. They maintain a page about Collembola genetics, BLAST searches etc here, where you can also search Orchesella cincta, Anurida maritima and others.
The NBN gateway, for these and all other life forms in the UK, is a wonderful resource to be found here.
Large, surface dwelling forms have a unique jumping organ called the furcula at the end of the abdomen, clearly visible on the Entomobryaabove. This is an escape mechanism. Species found deeper in the soil have little need for jumping or colours, and tend to be white without a furca. This can be seen in the Protaphorura armata below.
Protaphorura armata group; common animals but liking acid litter; a longstanding taxonomic quagmire! Roll on the grants to get them barcoded. |
Hymenaphorura nova new to UK, a groundwater specialist. (Littondale, Yorks, Nov 2009). |
Unknown species, family katiannidae. Probably new to science, probably an alien import. Lost Gardens of Heligan 2008, photo (c) Paul Ardron.
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All Collembola were thought to be free living, until recently when one superfamily the coenalitidae (of two species) were found to be living inside hermit crabs' shells. Their relationship appears to be commensal, possibly verging into mild parasitism. Not surprisingly, like all arthropod parasites, coenalitidae have very modified body forms. The fact that no other Collembola have parasitic bodyforms has not stopped people deciding that they are suffering from skin infections caused by Collembola. They don't, for the same reason that they don't have earthworms in their guts - being a parasite is a difficult lifestyle and needs special adaptations. If you think that you have problems with Collembola in your skin, then yes you certainly have problems, but they're nothing to do with Collembola! (Sarcoptes and Bourrellia are two medical possibilities, followed I'm afraid by delusory parasitosis).
My PhD at York University and ITE Merlewood involved studying Collembola/fungal interactions in a pine forest in Northumberland. This was followed by studies of Collembola on lowland heaths in Surrey and Yorkshire, and the species colonising industrial waste sites.
My hopes for the taxonomy of this group in the UK have been transformed thanks to collaboration with Brent Emerson now at La Laguna, Tenerife, and formerly UEA, who studies population genetics, notably (but far from only) mtCOI, the standard genomic barcode. We have a Systematics Association SYNTAX grant that saw me collecting Entomobryas and Lepidocyrtus from around the UK for COI barcoding (+ an optional nuclear gene for confirmation). This work has already convinced me that Entomobrya intermedia is a valid UK species, despite Steve Hopkin's doubts.
I am also collaborating with Carly Benefer of Plymouth university as part of a wider project to barcode UK soil fauna.
The 648 bps of mitochondrial COI sequence constitute the standard molecular barcode, held globally on the Barcode of Life . When PCRd and sequenced, COI sequences from Collembola have shown up ancient divergences within morphospecies. Collembola in the genus Lepidocyrtus around the mediterranean show divergences going back to the Miocene (>5MY), with minimal dispersal of gene variants away from their origins. Elsewhere, in Antarctica, the 'species' Friesea grisea has members >10 million years apart, and other cases where populations of the same species in adjacent valleys have been genetically isolated for hundreds of thousands of years. Brent uses (inter alia) the Roche 454 platform for high-throughput sequencing; his early 454 work on Collembola suggests endemic haplotypes occur on Tenerife. In future one will be able to take a jar full of freshly dead Collembola, digest out their DNA and run it on a 454-type platform then identify the clusters of amplicon sequences as species. To show that this is now possible (except that we need rather more validated Collembola barcodes) see this remarkable video about biomonitoring 2.0 . To understand the 454 procedure (which is conceptually similar to Venter's shotgun approach to sequencing the human genome but uses a multi-species mix of PCR products targetting one sequence), click on this 20 minute animation .
I have handled Collembola from a few exotic field sites; Nigeria (Dan Weaver's PhD), Ethiopia (helping Claire Ozanne), Costa Rica and St Helena.
The Costa Rican samples were pitfalls put out by Dr Erica McAlister (who
did her PhD at Roehampton with Claire Ozanne and myself). Erica now
works in entomology
at the BMNH, where the former head of collections Howard Mendel lent
me the Collembola collections from St Helena. The Costa Rican species are largely
unfamiliar and very diverse. The St Helena Collembola are (so far
anyway) very few in species and very familiar. I show you below the biggest
(easily making 2mm!) commonest and most distinctive of these; Orchesella cincta.
These are slightly paler than mainland O. cincta, but it is too early to
say whether this is of any significance. It is likely that St Helena had endemic Collembola, but that these got wiped out by invasive European species
(just like its giant earwig, and many more life forms on that remote island).
Orchesella cincta from St Helena, c. 2mm |
Orchesella cincta from St Helena, c. 2mm note the black band on abd.3 'cincta' means 'belted' in latin ,referring to the black belt on abd 3. This is the only UK springtail that can be confidently named with the naked eye. |
Relevant Publications:
Emerson BC, Cicconardi F, Fanciulli PP, Shaw PJA (2011). Phylogeny, phylogeography, phylobetadiversity and the molecular analysis of community structure. Philosophical Transactions of the Royal Society B, 366, 2391-2402.
Shaw PJA, Dunscombe M. and Robertson A. (2010). Hymenaphorura nova Pomorski, 1990 (Collembola: Onychiuridae) in the hyporheos of a karstic river: a new species and genus for the UK in a novel habitat. Entomologist's Journal and Record of Variation 122 (5), 213-215
Shaw PJA, Ozanne CMP, Speight M & Palmer I (2007). Edge effects and arboreal Collembola in coniferous plantations. Pedobiologia, 51, 287-293
Cole, L., Bradford, MA, Shaw PJA & Bardgett D (2006). The abundance, richness and functional role of soil meso- and macrofauna in temperate grassland – a case study. Applied Soil Ecology 33, 186-198.
Shaw PJA, Berg MP & Higgins J (2003). Orchesella quinquefasciata (Bourlet, 1843) (Collembola: Entomobryidae) from chalk grassland in the south downs. Entomologist’s Record 115, 45-48.
Shaw PJA (2003). Collembola of PFA lagoons in East London. European Journal of Soil Biology 39, 1-8
Shaw PJA & Buckhoree Z (2001). Collembola (springtails) of Brockham lime kilns, Box Hill. London Naturalist 80, 159-165.
Shaw, PJA (1997). Post-fire successions in Collembola on lowland heaths in the UK. Pedobiologia 41, 40-47.
Shaw, PJA & Usher, MB (1996). Edaphic Collembola of lodgepole pine Pinus contorta plantations in Cumbria, UK. European Journal of soil biology 32, 89-97.
Shaw, P.J.A. (1992). Fungi, fungivores and fungal food webs. In The Fungal Community, Vol. 2 (G.C. Carroll and D. Wicklow, Eds.), 295 - 310.
Shaw, P.J.A. (1988). A consistent hierarchy in the fungal feeding preferences of the Collembola Onychiurus armatus. Pedobiologia31, 179-187.
Shaw, P.J.A. (1985). Grazing preferences of Onychiurus armatus (Insecta: Collembola) for mycorrhizal and saprophytic fungi of pine plantations. In Ecological Interactions in the Soil (Special Publication of the British Ecological Society No. 4), (A.H. Fitter, D.J. Read & M.B. Usher, Eds.), 333-337.
back to Peter Shaw's work page
Last modified 30 Nov 2012