Well-Choughed

Drawers were open left, right and centre. It had been a long day in the lab and I was getting tired. The assemblage I was working on was interesting though and despite the clock ticking past dinner time I continued to compare specimens with those held in our reference collection.

I’d been woken so many hours earlier by my clock-radio clicking on to a discussion of what Britain’s national bird should be. I half listened to a roll-call of all the usual candidates –the robin, the blue tit, the blackbird – but also the wren and the red kite. This raised slightly uncomfortable questions for me as I walked into work, mulling things over in my half-awake state. Is Britain a nation? If it is then presumably all those birds I just listed are fair game. If, on the other hand, you believe the wren to be the national bird of England and the red kite to be the national bird of Wales, as many do, then surely those birds are not only taken but the very fact they exist suggests that Britain is not a nation and therefore cannot have a national bird.

It’s a largely frivolous debate, of course, without any real meaning for many people. I suspect the reason the idea is being mooted, however, is to focus attention on bird species. Perhaps the organisers might even be hoping for the endangered hen harrier to win the vote. Voting for a bird is an interesting concept – it suggests a level of support at a base level. That level of support (and identification?) can be galvanised in a very real way.

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The national bird of Cornwall is the red-billed chough (also sometimes known as the Cornish chough). Those from elsewhere may be unfamiliar with this unassuming bird or its story in Britain’s far Southwest. The last successful breeding season here took place in the early 1960’s. A few birds lived on (there was some speculation that several unsuccessful breeding attempts thereafter may have been from a gay pair) until the solitary survivor fluttered off this mortal coil in the 1970’s. By that point, there were already efforts underway to reintroduce the species.

This was easier said than done. Red-billed choughs are a long-lived, gregarious corvid. They live in family groups, the young remaining with their parents for 2-3 years, learning the ropes as it were. Once paired off, they stay together and use the same nest for the rest of their lives. Reintroducing them then, would probably involve moving an entire family group – except that family would be unfamiliar with its new home. Some attempts at reintroducing the birds were made in the 1980’s but these were unsuccessful.

At the turn of the millennium, Cornwall submitted a petition asking for devolution to Westminster and achieved Objective One funding from the EU. In 2001, the choughs returned. It seemed like an incredibly good omen. Chough watch was started. For a few years, the precise location of the (now successfully breeding) small population was kept secret and a 24hour watch on them was kept. Video footage and news of their activities was broadcast to an enthused Cornish public. The chough was depicted on the charter granting the earldom of Cornwall to Piers Gaveston in 1307 and still features on the Cornish coat of arms today, following public outcry when it was nearly removed. It was, in fact, once so closely associated with Cornwall that ‘the Cornish chough’ was used as a racial slur for Cornishmen.

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Recolonization by the red-billed chough in Cornwall is a process that continues to be monitored and actively managed through the creation of appropriate habitat – grassland close-cropped by traditional livestock breeds. In 2014 five pairs, now spread through three locations, raised 17 young. This might be thought of as some success but there’s clearly a long way to go.

Those specimens I was comparing with the reference collection were bird bones from the archaeological layers at Gwithian, in Cornwall. Among them were two corvid bones. The best match I could find for them was jackdaw but I wasn’t entirely happy with this. As I made my way back to my desk and prepared to enter them into the database my mind wandered back to that radio report in the morning. Could these be real Cornish ‘Cornish choughs’?

The rarity of choughs in twentieth century Britain (basically present on Islay and its surrounding islands and parts of the Gower Peninsula) means that they’re not in most osteological reference collections in this country. Fortunately though, the European corvids are one of the few groups of birds that have a good criteria published for differentiating them1. My misgivings were well founded – those two bones could not have been more like those of a chough.

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Historical records of the red-billed chough are surprisingly sparse. They were shot as game in Cornwall in the early nineteenth century; by as early as the sixteenth century Cornwall was allegedly the only place to find them. Just how far back does this association go though? Archaeological evidence is equally scant. Two sites have produced remains of the red-billed chough from Holocene mainland Britain: one from Mesolithic Port Eynon (where they are still found today) and a skull from fourteenth century Exeter.

These bones date from the fifth to eighth centuries AD and so are not only a rare find of British chough but push our known dates for its occurrence in Cornwall back by a millennium or more. More importantly than that however, they have been found at a site where the recent analysis of the animal bones has suggested an important role for pastoralist transhumance in the economy2.

A few summers ago we shared our campsite during our fieldwork in Mongolia with two resident families. One of these lived in an old Soviet structure adjacent to a well, the use of which they allowed us. The other lived in the same building and was a family of red-billed choughs. This was evidence for me that choughs do not mind the presence of humans so long as they have access to that short-cropped grassland habitat. In other words, their presence in this assemblage not only supports interpretations previously made but their presence against the background of those interpretations adds further support to the land management strategies being adopted to promote their recolonization of Cornwall.

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A short report detailing these finds will be included in the next issue of Palores and a short news story on the same subject will also feature in the next issue of Cornwall Today.

lion skeletonwww.zooarchaeology.co.uk

 

1. Tomek, T., Bocheński, Z.M., 2000. The Comparative Osteology of European Corvids (Aves: Corvidae), With a Key to the Identification of their Skeletal Remains. Wydawnictwa Instytutu Systematyki i Ewolucji Zwierząt PAN, Kraków.

2. Broderick, L.G., 2014. A Review of Subsistence in Mediaeval Cornwall and Analysis of the Mammal Bones from Mediaeval Gwithian. Unpublished MA dissertation. Institute of Cornish Studies, University of Exeter.


The Shoat

Shoats. Sheep-Goats. Sheep/Goats. Ovi-Caprds. Ovicaprids. For some reason never ‘geep’. Anyone who’s ever read a zooarchaeological paper or report from the last forty years will almost certainly have come across at least one of these terms and it’s been a bugbear of mine for quite some time. For anyone unfamiliar with the lexicon or the problem it’s thus: domestic sheep (Ovis aries) and goats (Capra hircus) are very difficult to distinguish from each other osteologically. Various researchers have looked at the problem over the years and it is possible to separate them through a select few elements1, but this is necessarily reliant on the vagaries of taphonomic factors as well as researcher experience. Careful readers will note that I said ‘a few select elements’ though – so even if preservation and recovery are perfect, and the zooarchaeologist vastly experienced, there will still be a large number of bones that are impossible to definitively assign to either species.

Hence the Shoat. It’s been pointed out before that the two species, although closely related, are vastly different ecologically, ethologically and symbolically and so we should not, perhaps, consider them in this interchangeable way2. These are valid points which all researchers should consider, even if the fundamental aim of separating them proves more difficult. My gripe is slightly different however. It is, in fact, essentially etymological. The shoat, the sheep-goat, exists – as the BBC kindly reminded us this week.

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Before zooarchaeologists the world over roll their eyes with irritation though, let me elaborate. Sheep-goats exist, as the BBC cameraman delighted in showing us, and we should not be using the term to describe an animal whose precise identification we’re unsure of. I would hope my peers will agree with me that as scientists we have to be very careful and precise in our use of language – it could be said that the value of the research depends upon its effective communication. Sheep/goat is perhaps marginally better but Ovicaprid is meaningless. There is, however another alternative – one which I, like many other specialists, have used for years: caprine. Perhaps some people have avoided the noun through confusion with its definition as an adjective (goat-like); when used as a noun, however, it means any species belonging to the tribe Caprini. These are basically sheep, goats and their wild relatives.

I think this is important to get right. Working principally with pastoral societies I’ve identified a lot of caprines over the years and been frustrated that I’ve often been unable to take identification further than that. I’ve never identified a sheep-goat before though.

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Also reported on the BBC in the last fortnight, the annual British garden birds survey saw a large rise in the number of blue tits. Regular readers of this ‘blog will know that I’m very keen on birds – both in the present and as zooarchaeological subjects. The paucity of garden birds in archaeological assemblages often puzzles me, as largely commensal species they should be far more common and it perhaps reflects the poor preservation and recovery of their small, fragile bones. Alternatively, it may reflect different patterns of waste disposal on past habitation sites and it’s noticeable that the wild bird species that are most often found on archaeological sites are usually those that were probably eaten. Last year, for example, I filed a report for Exeter Archaeology on the Roman period remains from the Princesshay development in the city centre (Broderick, 2013, Zooarchaeologica Isca Dumnoniorum) and found that woodcock (Scolopax rusticola) was the fifth most common ‘species’ on the site – following caprines in fourth place, a designation which certainly featured both sheep and goats.

clip_image003www.zooarchaeology.co.uk

 

  1. Such as some teeth and the mandible (Boessneck, 1969; Halstead, et al., 2002), the distal humerus, distal tibia, astragalus and calcaneum (Boessneck, 1969; Payne 1969, 1985; Kratochvil, 1969) and the distal metapodials (Boessneck, 1969). For full references see any of my reports.
  2. Barbara Noddle’s article of 1994, ‘The Under-rated Goat’, in the book ‘Urban-Rural Connexions’ remains an excellent overview of this topic although it’s been picked up by many more authors since, such as Umberto Albarella and Kristine Jennbert.

It’s a Game Old Bird

This morning, an article in Nature announced to the world a newly discovered early bird – Aurornis (or click here for the summary, here for the BBC summary). This bird (a rather snazzy artist’s impression is included below) seems to have existed around 160 million years ago, that is around 10 million years earlier than Archaeopteryx. From my, distant, perspective, 10 million years is roughly contemporary once you reach the Jurassic. The authors of this paper plainly disagree though and suggest that Aurornis xui is an ancestor of Archaeopteryx.

That’s significant. For those of you that don’t keep up with the dynamic, catty, world of bird taxonomy, Archaeopteryx was fairly recently relegated by many from avian to non-avian dinosaur status (yes, recent work suggests that birds are so closely related to dinosaurs that we now have to use the cumbersome equivalent of the ‘non-human ape’ favoured by primatologists). So, probably the most famous ‘first bird’ is now a bird again; everyone can rest easy (for now – I fully expect a response paper in the next issue disputing this taxonomy).

Source: Nature article linked in text above

 

So, what does all this mean for someone who specialises in the late Quaternary? Not a lot really, it’s an interesting diversion from the day-job but all this squabbling scarcely affects bird research in the Pleistocene and Holocene except for the uncertainty surrounding much of the taxonomy of our modern avifauna. I fully expect it to be another twenty years or so before a consensus is reached as to living bird taxonomy, let alone fossil; in practical terms, for now, perhaps I need to revise my ‘earliest bird’ date in my teaching hand-outs?

Speaking of which, I’ll again be teaching the ‘birds’ class in the University of Sheffield Introduction to Zooarchaeology shortcourse in two and a half weeks’ time. Anyone who might be interested in attending that course is encouraged to book soon – there are one or two places still available as I write this but they’re filling up fast. For more information and to book a place see the course website or else contact one of us (course staff) directly. Finally, in a partly contrived way of making this post more relevant to the ‘blog, I’m including a free sampler of the course here! After the break you’ll find an extract from my hand-out for the birds class.

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www.zooarchaeology.co.uk

 

Birds in Zooarchaeology

There are c.9,500 species of birds in the world and over 200 in the UK (precise figures are hard to establish due to taxonomy and migratory & vagrant species), compared with 4,300 and 60 mammals, respectively. Birds evolved much more recently than mammals (around 160 million years ago as against 225mya; the Neornithes, the sub-class which contains all modern birds, evolved around 85mya) and DNA research suggesting that birds are far more closely related to each other than we previously realised led some researchers to call for a drastic overhaul of bird taxonomy in 1990. More recent (refined) molecular, fossil and anatomical evidence is beginning to resolve some of these disputes but for the time being no single taxonomy is recognised universally; meaning that the taxonomy of several species, genera and even families is currently much disputed. For these reasons, it can be appreciated that secure identifications based on skeletal remains present a challenge to the zooarchaeologist. The general principles of identification and recording remain the same as for mammals, however, and indeed most of the bones are analogous in function and structure, even if there are notable differences.

Birds interact with humans in several different ways – as food, as guards, as objects of beauty, as sources of secondary products (eggs and feathers), as commensals, as pets, as hunting companions and as pest controllers – and to some degree their presence in a zooarchaeological assemblage can reflect any or all of these different roles. Interpretations of these roles are usually based on analogy with ethnographic or historical records and some direct observations such as butchery marks on the bones, medullary bone or the presence of egg shell in the assemblage.

Medullary bone and eggs are reliable indicators of seasonality, as are migratory birds but we need to consider whether or not migration patterns may have changed when using these species as seasonal indicators. More generally, all wild birds can be ecological indicators when interpreting past environments and the records themselves are useful sources for biogeographical research.

Domestic birds are usually less important than domestic mammals for food but the domestic fowl, Gallus domesticus, (there is, oddly, no specific English word for this bird: ‘chicken’ technically refers to a female domestic fowl under the age of one year; ‘hens’ are the female of any bird species and ‘chook’ is not widely recognised outside of Australia and the UK: all of which clearly shows the need for using binomial classifications in scientific literature) is the most numerous higher vertebrate in the UK and on earth. The importance of birds as food, then, should not be underestimated and wild birds in particular, as food or not, can also be important indicators of status.

KEY TEXT:

Serjeantson, D., 2009. Birds. Cambridge University Press, Cambridge.

TAXONOMY AND BRITISH BIRD GUIDES:

Gill, F. & Donsker, D., 2013. IOC World Bird List (v 3.3). Available at http://www.worldbirdnames.org

Svensson, L., Mullarney, K., Zetterström, D. & Grant, P.J., 2010. Collins Bird Guide [2nd edn.]. Harper Collins, London.

BONE IDENTIFICATION ATLASES:

Bocheński, Z.M. & Tomek, T., 2009. A Key for the Identification of Domestic Bird Bones in Europe: Preliminary Determination. Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Kraków.

Cohen, A. & Serjeantson, D., 1986. A Manual for the Identification of Bird Bones from Archaeological Sites. Archetype Publications Ltd., London.

Tomek, T. & Bocheński, Z.M., 2000. The Comparative Osteology of European Corvids (Aves: Corvidae), with a Key to the Identification of their Skeletal Elements. Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Kraków.

Tomek, T. & Bocheński, Z.M., 2009. A Key for the Identification of Domestic Bird Bones in Europe: Galliformes and Columbiformes,. Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Kraków.

FURTHER READING:

Acta Zoologica Cracoviensia 45 (2002) http://www.isez.pan.krakow.pl/journals/azc_v/azcv45.htm

Archaeofauna 2 (1992)

International Journal of Osteoarchaeology, 7(4) (1997)

Grupe, G. & Peters, J., 2005. Feathers, Grit and Symbolism: Birds and Humans in the Old and New Worlds. Verlag Marie Leidorf GmbH, Rahden/Westfalen.

Poole, K., 2010. Bird Introductions, in: O’Connor, T.P. & Sykes, N.J. (Eds.), Extinctions and Invasions: A Social History of British Fauna. Windgather Press Ltd., Oxford. pp. 156-165

Prummel, W., Zeiler, J.T. & Brinkhuizen, D.C., 2010. Birds in Archaeology: Proceedings of the 6th Meeting of the ICAZ Bird Working Group in Groningen (23.8 – 27.8.2008) Barkhuis Publishing/Groningen University Library, Groningen.

Serjeanston, D., 1998. Birds: A Seasonal Resource, Environmental Archaeology, 3, 23-34

Serjeantson D., 2010. Extinct Birds, in: O’Connor, T.P. & Sykes, N.J. (Eds.), Extinctions and Invasions: A Social History of British Fauna. Windgather Press Ltd., Oxford. pp. 146-155

Yalden, D.W., & Albarella, U., 2009. The History of British Birds. Oxford University Press, Oxford.


Salt and Mud on the Atlantic Coast of France

I’ve just returned from a week’s fieldwork in France collecting invertebrate samples for analysis as a part of the EcoSal Atlantis project.  Working on the ecological side of the project, we’re particularly interested in how these intensively managed landscapes provide a habitat for a consistent community of invertebrate species and (often) migratory birds along Europe’s Atlantic coast, from Portugal to Scotland.

This was the first portion of fieldwork in the project and more will follow this year and next as we seek to establish precisely how these ecosystems develop through the year and how they are connected to eachother.  More information on the research project can be found at http://ecosal-atlantis.ua.pt/ (a website concerning the British portion of the project is in production).