The Mesolithic as a period has been re-engaging public interest in recent years. South Yorkshire has played a key role in the early recognition of the period in Britain and in establishing a chronology for the period. However evidence in South Yorkshire is particularly challenging to research and manage. The period in this region is poorly understood as interpretations are largely based on a few limited excavations dated prior to the 1970s as well as many ‘findspots’ (which largely reflect patterns of differential survival and visibility). Despite excellent quality research into existing collections, interpretations have been constrained by the nature of the record and tend to recycle debates over comparisons between ad hoc assemblages dating back over half a century. As a result surprisingly little is understood about the distribution of Mesolithic activity across the region or what surviving evidence remains. There is nonetheless potential for a much improved understanding in the future, particularly through research into undisturbed sites of high integrity and/or those with organic preservation in certain locations, and for a much greater public interest and engagement with the distinctive character of the Mesolithic in the region. There are however serious threats. South Yorkshire, lying at the southern limit of upland bog formation, is uniquely vulnerable to the effects of climate change on blanket peat. The subsequent influence of changes in vegetation and increased erosion on Mesolithic sites under peat will have an impact on research and management.
What makes the Mesolithic particularly challenging period to research and manage? In general terms:
These challenges are particularly acute in South Yorkshire because:
Mesolithic occupation lasted over five thousand years, from around 9500BC to around 4000BC years. Evidence of hunting and gathering communities from the period, predominantly in the form of remains of chipped stone industries, are found across the region, ranging from ‘findspots’ of a few surface flints to larger assemblages which must have been larger or more frequently occupied locations. Findspots are particularly concentrated in two main north-south ‘bands’ however (see figures 1-3 and also figure 4 – records from Tim Cockrell’s recent PhD, which expands the HER record). These two main concentrations of findspots relate to millstone grit geology of the Pennine uplands in the west and the magnesium limestone to the central-east portion of the county (marked grey and blue respectively on the HER plots). Elsewhere differing reasons influence the relative lack of Mesolithic material – large urban development such as around Sheffield and Doncaster is likely to have destroyed deposits from the Mesolithic, whilst large areas of alluvium along river valleys will conversely have covered deposits. There may also be parks or wooded areas where sites remain undisturbed (Cockrell 2016), potential high integrity sites under peat (Spikins 2010), and possibilities for organic preservation in any low lying waterlogged deposits.
Finds from the Pennine uplands have been particularly significant in the history of the Mesolithic as a period. Peat in these uplands began to erode from the end of the 19th century, as a result of a combination of industrial pollutants from nearby cities and overgrazing by sheep. This erosion revealed Mesolithic artefacts previously sealed under peat, with collection from erosion patches and excavations in the early 20th century onwards contributing the main body of the Mesolithic assemblages and findspots in the HER record. Flints tended to be recovered eroding from sites particularly located at plateau edges with good views to the lowlands. Substantial quantities of flint were found eroding from under peat deposits, sparking an interest in the period, but however with only a very small minority of such finds reaching public records (Mellars pers. comm). ‘Flinting’ on the moors, became a popular hobby in the 1960s and 1970s and included active digging, with no real appreciation that flints may be eroding from coherent sites with spatial integrity.
At ‘Flint Hill’ (Broomhead Moor) for example the Radley, Tallis and Switsur comment in 1974:
‘This latter name derives from a time when flint was collected on now-healed exposures for the making of grit, once used in the rearing of grouse. Three Mesolithic sites have been found on Flint Hill…There are four distinct chipping floors with a scattering of artifacts between them. The area is almost 200 yds. by 150 yds., and much of it is still peat covered. Both flint and chert have been taken from under the peat’
The relationship between findspots and areas of landscape with significant peat erosion is not immediately clear from large scale distribution maps. However rather than being recovered from the most denuded areas of central blanket peat (figure 5), findspots in the southern Pennines are associated with marginal peat face erosion (figure 6) (Penny Spikins 1999). The tendency for marginal face erosion to expose a large area of past land surface is one explanation for this patterning, however a preference for repeated occupation of plateau edge locations also associated with the heads of rivers in the Mesolithic is also an important contributory factor.
Historically the most important site in the region is probably that at Deepcar, found at a slightly lower elevation overlooking the confluence of the Porter and the Don. Here over 22,000 flints and the remains of a structure were excavated, with Deepcar becoming the ‘type site’ for Deepcar industries which were identified across the country (Radley and Mellars 1964), and found predominantly in river valley locations (Barton and Roberts 2004). Deepcar, as well as other Mesolithic sites in the southern Pennines, formed a key part of the highly influential synthesis by Roger Jacobi and in the dating of the period, with the identification of the early and late phases (Switsur and Jacobi 1975; Jacobi 1978) which remain the main defining distinctions today (Barton and Roberts 2004).
Peat erosion in the southern pennines has been amongst the most severe on a global scale, with large areas being denuded (figure 7). This raises the issue of what mesolithic evidence remains in the uplands and its nature. Much of this marginal peat where findspots tend to concentrate has been destroyed by 20th century erosion (as is clear from the quote above), and it remains unclear whether the small numbers of finds recorded in the more recent PAS record (figure 3) reflect a lack of remaining material, or peat regeneration over remaining sites.
Trial excavations at March Hill in the early 1990s only a short distance north of the border with South Yorkshire aimed to address the question of whether intact Mesolithic sites remained at the marginal peat face, the nature of such sites, and the threats to them. Large areas had been destroyed by erosion, antiquarian excavations and more recent diggings by amateur collections (many of which for private collections which remained undisclosed) at this site. However in two of four locations excavations revealed surviving deposits with extraordinarily spatial integrity, at one of these with most finds having moved less than a cm from their original position, the highest recorded integrity of any Palaeolithic or Mesolithic site (Spikins et al. 2002). The explanation for the minimal movement of finds most probably lies in incipient peat formation at the time of deposition which will have restricted the normal agents which disturb finds (such as burrowing animals and plant roots). Although a common observation is that Mesolithic artefacts are found below, rather than within, the peat (Garton 2017) in the case of site A March Hill finds were vertically distributed across the peat/soil interface with exceptional integrity (from coordinate modelling and refitting). Mesolithic occupation can therefore occur not long prior to peat formation, both the ease of finding artefacts from erosion patches where peat has already eroded and the difficulty in finding artefacts within the peat itself probably contributing to the idea that finds within the peat are rare. Excavations at site A March Hill revealed a series of hearths, and the seating locations of individuals around the hearths knapping flint, and has been interpreted a ‘snapshot in time’ of Mesolithic occupants, whilst further to the south at Lominot different phases of occupation (dating to the early and late Mesolithic) were stratigraphically identifiable ( Spikins 2002). Given regeneration of the upland moors due to a reduction in grazing and changes to drainage any remaining similar sites in the southern Pennines were judged to be best preserved in situ. The effects of climate change on upland peat may warrant a re-appraisal (see ‘threats and management’ section).
Most of the HER record for the Mesolithic dates to a time when finds were actively destroyed through erosion (in the Pennine uplands) or agricultural practices (in the Magnesium Limestone). The timing of this recovery has thus severely constrained the usefulness of the current resource, with no modern excavations in the uplands and lithic collections, drawn from fieldwalking or eroding surfaces, being biased in both their location and their constituents
Most research has focused on interpretations of what are somewhat ad hoc collected assemblages. The earliest research, following peat erosion in the 1950s and 1960s, made perhaps the greatest impact on our understanding of the period. Publications by Radley (Jeffrey Radley, Tallis, and Switsur 1974), and Radley and Mellars (Radley and Mellars 1964) and later Jacobi (Jacobi 1978) revealed a distinction between an early and a late phase of the period on the basis of microliths (tiny worked points) as well as relationships between assemblages at different sites. Larger microliths were found to be typical of the early phase, made on raw material which travelled some distance.(such as from the Yorkshire and Lincolnshire Wolds) and with sites often found at generally lower elevation. Smaller microliths tended to belong to the later part of the period (reaching sizes down to a few mm in length) and tend to be made on local raw material, with recorded ‘sites’ often apparently of smaller dimensions.
Subsequent research, based on essentially the same collections, tends to follow these debates, adding explanations or refinements to discussions of key themes of mobility and chronology. Myers added an ecological and functional dimension to the discussion of why microliths changed in form (Myers 1988) for example. Proposed mobility patterns and how they changed have also remained a source of debate (Donahue and Lovis 2006). Key PhD research has included Reynier’s research suggested further chronological distinctions within the early Mesolithic (Reynier and Others 1997) whilst Preston’s research argue for alternative mobility patterns (Preston 2009). Cockrell (Cockrell 2016) has recently gathered together existing evidence and brought new concerns with relationships to landscapes (Conneller 2005) and to a movement away from defining seasonal rounds (Penny Spikins 2000) to the period. He highlights repeated occupation of certain locations and associations with rivers as sources of movement.
Finds of substantial structures at Star Carr in the Vale of Pickering and elsewhere (Conneller et al. 2012) illustrate the potential for further Deepcar like structures to be found in south Yorkshire itself, and to be excavated with modern methods.
Several factors can mitigate against recovery of Mesolithic finds. Commercial excavation and fieldwork for example often fails to appreciate the extremely small size of many Mesolithic finds. Mesolithic sites can also be threatened by development. As well as typical threats due to development deep ploughing can damage or even destroy existing subsurface sites (as illustrated by Cockrell for the magnesium limestone zone). Upland wind turbines can also threaten sites under peat, not merely through the turbines themselves but through access roads built across the moors. Probably the most serious threat to Mesolithic sites however comes from the effects of climate change on Mesolithic sites preserved under upland peat.
Upland blanket bogs are fragile ecosystems and uniquely sensitive to changes in temperature and rainfall. Significant steps were taken in south Yorkshire to remedy what can be seen as the ‘first phase’ of human impact on upland peat landscapes in which substantial areas were severely degraded through the effects of industrial pollution and overgrazing in the early and mid 20th century. Projects as part of ‘Moors for the Future’ have had an important in the regeneration of peat uplands for example through the reduction in grazing and changes to upland drainage as well as active planting and over interventions. As a result there has been substantial regeneration of the upland peat in South Yorkshire. There will however be a ‘second phase’ of human impact on upland peat due to global changes in climate, and whilst land use practices have a substantial impact in retaining upland peat, global climate change may be a tide that cannot be turned in the same way.
Mesolithic sites under upland peat can be some of the most high integrity sites known. This is because if material is deposited at a time of incipient peat formation the normal agents of movement (burrowing animals, root action) are not active and finds stay very near to their original locations. At March Hill site A for example most finds lay within about 1cm of the original land surface, and re-fitting demonstrated coherent ‘snapshots’ of activity around four hearths (figures 8 and 9). Thus these sites can potentially provide highly significant evidence about the period, as long as they are recorded with the exceptionally high resolution methods demanded (Spikins, Ayestaran, and Conneller 1995; P. Spikins et al. 2002).
Figures 8 and 9: distribution of finds at March Hill (Marsden Moor) in plan, and in relation to palaeosol (P. Spikins et al. 2002)
The upland peat in South Yorkshire is one of the regions most vulnerable to climate change because it lies at the limits of ecological conditions which promote peat formation (Gallego-Sala and Colin Prentice 2012). Current temperatures are on average already 0.5 – 1 degree C higher than in the 1970s, and some degree of continued climate change is inevitable due to previous emissions. In fact even with strong international action global temperature has a fifty percent chance of rising by 2 degrees C by the end of the century (Committee on Climate Change 2017).
Firstly, climate change models predict increased sediment loss through erosion in the regime, under the influence of more variable climate regimes (Li, Holden, and Irvine 2016). Such erosion may not be gradual but as a result of ‘freak’ events such as unusually dry summers which dissicate peat, followed by sudden high rainfall events in autumn and winter. Land management practices mitigate against the effects of such events, however remaining marginal face peat deposits potentially overlying high integrity sites may be particularly vulnerable to this type of erosion. Plans for future management and research cannot assume that erosion will be a gradual process as sudden ‘freak’ erosional events are more likely.
Secondly, climate change will influence peat uplands through changing ecological zones. Blanket bog becomes unviable in all of the current climate models by 2050 (Committee on Climate Change 2013, see figure 10). The timescale of subsequent changes is unclear, Natural England for example note that ‘Peat will persist for long periods even when new peat is not forming’ (Natural England 2010, NE 257 Englands Peatlands, p34). However the nature of the vegetation will ultimately change, and we may see the rise of more resistant sphagnum, an increase in scrub and heathers or more tussocky peat. Changing vegetation may seriously impact sites with high integrity at a depth where roots affect the deposits for example.
We may currently occupy a time frame between the first phase of human impact on upland peat (due to local air pollution and overgrazing) and a second phase (under the influence of global climate changes). This is therefore the point to consider the threats to Mesolithic sites under peat posed by climate change (over the short, medium and long term), whether preservation in situ is viable and whether a pro-active approach to generating a well documented record of the upland Mesolithic is now necessary. Public engagement and a co-ordinated approach between the regions affected (Derbyshire, South Yorkshire, Greater Manchester and West Yorkshire) will be important.
Schools: The Mesolithic (under the term ‘stone age’) is now part of the National Curriculum, at Primary school, key stage 2. There is thus potential for South Yorkshire to develop local schools resources, much as has been carried out for other regions, and to encourage engagement with museum collections. We might even (not too fancifully) imagine visiting sites such as Deepcar with an app with a overlay of the structure recovered there.
General Public: A broader public interest likely to focus around the small size of microliths (as a feature rather than a limitation), the relationship of Mesolithic peoples to their environment and specific issues such as the design of hunting weapons. The region has been important in our understanding of the period, and there are likely to be museum collections (for example of unstratified finds) which could be used in schools or other public engagement.
For further information see:What is the Mesolithic?
Research questions specific to South Yorkshire develop broad national and regional frameworks within the evidence specific to the region. These frameworks include the English Heritage Research Strategy for Prehistory, East Midlands Research Agenda (Knight, Vyner and Allen, 2012), Mesolithic Research and Conservation Framework (Blinkhorn and Milner, 2013) and the Research Framework for Holocene Lithics (Lithics Studies Society, Gardiner 2004). Naturally that evidence changes through time, and thus new questions can open up. For example the current record doesn’t include any evidence for Mesolithic art or for burial (as such evidence is extremely rare) but if such evidence is recovered in the future new questions can be introduced.
In general terms research directions follow three main related themes, within which specific questions can be addressed.