Castles and Coprolites

It's been a while since I did a monthly microfossil or micrograph post, so I thought I would share this nice example of something combining both. This is a midden deposit from the early Neolithic site of Bonkulu in Turkey - the large greyish object in the middle is a very highly silcified conjoined phytolith from a reed stem/leaf, embedded in a matrix of mixed ashy debris. There is a resemblance to an earlier micrograph I posted from the Babylonian site tell Khaiber, which also contains large mutlicelled reed phytoliths. The deposits at Boncuklu are chock full of these large Phragmites reed phytoliths, likely to be from burning these substantial plants as fuel. The macrobotanical record from the site also contains large volumes of reed stem charcoal.

Two posts crossed my Twitter feed last week that got me thinking. Both are related to experimental archaeology and use of wetland resources. If you are a regular reader of my blog (or indeed my academic papers) you will have noticed that I talk a lot about the environment of Çatalhöyük, and how this may have influenced human activity in the Neolithic. You will also notice that I have criticised some of the early interpretations which, to me, present a simplistic interpretation of evidence that doesn’t consider the complexity of the environment, or people. Çatalhöyük was situated in a wetland environment, and there have been debates over the influence this had on agriculture. Where were people growing their crops if the local area was not suitable for agriculture?  One theory suggests people travelled to fields that were located many km away from the site, which in turn has implications for social organisation. This always bothered me, firstly because of the limitations of the ...

Yikes, I can't believe it's already June, and time for a new microfossil! This month we have firstly a general view of a phytolith slide from the site of Boncuklu in Turkey , at x100. This just gives you a taste of how chock full of microfossils these slides are! I have highlighted two particular phytoliths here shown at x400, both are conjoined phytoliths from sedge. Sedges, or Cyperaceae, are monocots which are similar to reeds, and are associated with wetlands. Though significantly, it should be noted that they can be found in other types of environment as well. At Boncuklu we know from other environmental work that a local wetland habitat was quite likely, and we also see a lot of reed phytoliths in these samples. The blocky square pattern is typical of sedge phytoliths, though it is difficult to say anything about which species they might be from. This sample is from an ashy layer in a midden deposit, and it could be that the sedges were burnt alongside reeds, either delib...

Something a little bit different - this month I have an image of a siliceous sponge spicule! This show up occasionally in my phytolith slides, and are very distinctive. Sponges, or poriferans to give them their scientific name, are characterised by an unusual feeding system that involves drawing water in through little pores in the outer walls, and filtering food from the water as it moves around their bodies, before being pumped back out again. This flow of water occurs in one direction and is driven by beating flagella. Sponge spicules provide structural support and protection from predators. They come in all sorts of shapes each with a different name - the single spike shape that you can see looks like a monaxon, though it is also possible that is has broken off a larger 'polyaxon' type. The formation of spicules seems to be better understand than that of my other favourite siliceous microfossil, the phytolith, and is controlled largely genetically, but with environmental c...

For 2015 I have decided to replace my Micrograph of the Month feature with Microfossil of the Month. I will likely return to the thin section micrographs at some point, but as I am going to be working on phytolith and ash samples for most of this year, I figured it would make sense to feature some of these on the blog! Who knows how long I will be able to keep it up - from past experience of the sites I am working on, I may be limited in the range of examples that I will find! As a refresher (and for those of you new to the blog), microfossils are any fossil remains that are too small to see easily with the naked eye, but can be identified under the microscope. I work on plant microfossils, specifically silica phytoliths, which are 3D 'impressions' of plant cells and tissue. When the plant is alive, it takes up silica from the ground, which is then deposited inside and between the cells, forming 3D replicas of the cells that preserve when the organic part of the plant decays. T...

Bulliform cells in modern Zea mays tissue (source: Visuals Unlimited, Inc) Fellow animal dung enthusiast Sarah Elliot at the University of Bournemouth shared this fab little article describing the use of 'Eco goats' to manage invasive plants in the US . It is especially interesting that they note the use of goats as a pesticide-free way to manage Phragmites reeds. These reeds have distinctive phytoliths which archaeologists call 'keystone' bulliforms, which are relatively large single cell phytoliths that are named as they are said to resemble a Roman keystone arch in cross section.  In transverse section they look a bit sausage shaped, and within a plant these cells are 'stacked' next to each other as part of the upper epidermis (the plant 'skin'), and are related to water storage. If you're a botanist you might also call these motor cells, because during times of water stress, they shrink and cause leaves to fold or curl up. Phragmites phytoli...

In your sediments, post-depositionally disturbing your stratigraphy. Here we have examples of roots from modern plants that have grown into the archaeological deposits. They are easily distinguishable from archaeological plant remains as the tissue is fresh, organic and well preserved. Photo A shows a root that has grown into soft, ashy, compact midden at Boncuklu, Turkey. You can see clearly the void that has been created from the root's growth, which is the same shape as the root itself (3). We can also see a fragment of shell (1) and some small crushed bone fragments (2) embedded in the deposits. Photos B and C show close ups of modern root from Cesis Hillfort, Latvia. In B you can see where the root is divided into two rootlets whilst C shows the cell structure very clearly. Each of those 'jigsaw' shapes is an individual cell - it is cells like this that become infilled with silica during the growth of the plant, to produce phytoliths. This example of 'jigsaw' s...

Melted silica in ashy deposits at Neolithic Boncuklu (Turkey) above, and Kamiltepe (Azerbaijan) below. Silica is one of the most common components of plant ash, and is often seen in the form of phytoliths. In the case studies I have worked on, phytoliths in ash can have >50% abundance in thin section, and there may be millions of them per gram of sediment. Less common are these features, also composed of silica but with a very different appearance. These are 'bubbles' of melted silica, and they occur when silica is present in conjunction with alkali salts. Heating under these conditions causes the silica to melt and form what has been termed a 'glassy slag' or vesicular glass (e.g. see Canti 2003). The word vesicular refers to the gas bubbles you can see within the larger silica mass (also bubble shaped!). I prefer to call it melted silica rather than use the word 'glass' as it can be confusing in an archaeological context. The two examples here are from...

Ashy midden deposits in thin section. Since starting my new job as a Research Fellow, I feel like the amount of actual research I have done is limited! But I have spent plenty of time applying for money to do research. It must be nice being a researcher in a subject that doesn't require expensive laboratory work or sample processing. I have daydreams about spending all my time just reading and writing in a nice quiet library somewhere, preferably overseas and sunny. On the plus side, the more funding applications I write, the quicker it gets, and sometimes I even get the money! I just found out recently I was awarded a University of Edinburgh Munro Research Grant to complete the pilot work I've been doing on material from Boncuklu Hoyuk ('the place of beads') in Turkey. I started working there after finishing my PhD, I think the first samples I collected were in 2009, but due to the expense of producing thin sections, I was not able to get them processed at the time...

I just recieved a nice suprise in the post today - a new set of micromorphology slides from the 2009 field season at Catalhoyuk and 2010 season at Boncuklu . I have technically been working on material from Catalhoyuk since 2003, when I analysed midden samples at the University of Reading for my MSc thesis, though I didn't visit the site myself until 2004 when I started my PhD. I've been working on the site ever since, in collaboration with Dr Wendy Matthews (micromorphology) and Dr Ian Bull (coprolites). It really is a fantastic case study for the type of high resolution approach that I am interested in. As you can see from the following pictures, the level of preservation (particularly in the lower, deeply buried deposits) is phenomenal, and enables reconstruction of past human acitivites to the extent that we can recognise individual actions such as the dumping of a fine layer of ash. More recently I have become involved in work at Boncuklu, which is being led by Professo...