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My work diary of last week, in which members of the public put a valuable part of the collection at risk with their smart phones, tiny floating snails cause a flurry of visitors and microfossils are mentioned on the Test Match Special cricket commentary(!) in a varied week for the curator of micropalaeontology.




First up is a trip across the Museum to the Nature Live Studio with some delicate specimens that will be the subject of my two public talks later in the day. We can't move large items across the Museum during opening hours and, with the galleries filled with summer visitors, this is more than sensible at present.


In the Nature Live Studio with host Tom Simpson - a CT-scan of a Blaschka glass radiolarian model on the screen.


All of the specimens in my care bar the one in the Treasures Gallery are housed behind the scenes, so regular visitors might not even know that we have microfossil collections. A previous head of palaeontology collections calculated that we have as few as 0.001 per cent of our fossil collections on display.


If you haven't been to one yet, the Nature Live events are a great way to bring these parts of our collections out for the public and allow us to talk about our science. The incredibly delicate and unique Blaschka Glass models of radiolarian microfossils are always a big hit, but we have to ask a smart phone-brandishing throng of children and their parents to move away from the specimens after the first show as a mother leans over the barrier and takes a picture on her phone from right above the specimen. We add two extra barriers for the second show!



I've had an enquiry from The Geological Magazine asking me to review a book that I have almost finished reading. I have to think carefully about saying yes or no. Receiving a free copy is the usual bonus for undertaking these tasks but, as I have a copy already, dedicating a lot of time to a review does not seem so appealing.


I decide that I shall send the extra copy to my student in Malaysia but I think I will wait until after she has finished writing up her MSc thesis. Her first chapter arrives today for comment as do some proofs for a book chapter on microfossil models that I have written. Much of the day is spent checking these and providing additional information requested by the editors of the book. It will be about the history of study of microfossils and will have an image of one of our microscope slides on the cover.




The galleries are packed with summer visitors but it is relatively quiet behind the scenes with many staff on annual leave, away on study trips, conferences or fieldwork.


This quieter period is a good time to catch up on some of the documentation backlog so today I finish documenting a new donation, continue to work on a large dataset relating to specimens from the Challenger Collection, and register 30 Former BP Microfossil Collection specimens that are due to go out on loan to the USA.


I spent my first 6 years at the Museum on a temporary contract curating the Former BP Microfossil Collection so it is always satisfying to see it being used by scientists. We have big plans for this collection in the future. However, I feel that I will need to do more than wait for a rare quiet day if I am to meet my part of the databasing targets set by the Museum. We plan to have details of 20 million of our specimens on our website within 5 years.




An enquiry has come in this week about our heteropod collection. These are tiny planktonic gastropods, or literally floating snails. They are of great interest to scientists looking to quantify the effects of ocean acidification because they secrete their shells of calcium carbonate directly from the seawater that they lived in.


Measurement of carbon and oxygen isotopes from fossil examples can give details of the composition of ancient oceans and help to quantify changes over time. I mention the enquiry to staff in the Life Sciences Department and three visitors arrive to look at our collection within a day, including two from the British Antarctic Survey looking to develop projects on ocean acidification.



It is back to documentation again, a task I often save for days when the cricket is on. I am amazed when I hear dinoflagellates mentioned during the Test Match Special commentary. Dinoflagellates are protists that are a major consituent of modern and fossil plankton. We have thousands of glass slides of them here at the Museum within the micropalaeontology collections.


straussii_cookii_montage.jpgNew species of Australian Jurassic dinoflagellate Meiogonyaulax straussii (1-4) and Valvaeodinium cookii (16-20) published by Mantle and Riding (2012). Images courtesy of Dr Jim Riding, British Geological Survey.

A regular visitor to our collections who works at the British Geological Survey in Nottingham has described two new species of Jurassic microfossil from the NW Shelf of Australia and named them strausii and cookii after the former and current England cricket captains and Ashes-winning opening batsmen. It causes much merriment in the Museum microfossil team as another former England Captain, Michael Vaughan, remarks on the radio that they look rather like omelettes.


Cricket is the theme for today as I attend a lunchtime retirement party for a former cricketing colleague at the Science Museum next door. I leave a colleague to take a visitor to lunch but come back to find that he has gone home sick and the visitor is still here with a list of requests that account for the rest of the day...


According to January 2013 figures on their websites, the American Museum of Natural History (AMNH) has more than 32 million specimens, the Smithsonian Institution in Washington over 126 million  and the Natural History Museum over 70 million. Do we really know how many specimens we have here at the Museum? Are these figures meaningful and does it matter if we haven't estimated correctly?


When I consider the collections in my care I often have a chuckle about these figures and wonder if I could ever even get close to estimating the actual number of specimens in my collection. Take the jars and bottles below for example; there are literally hundreds of thousands of microfossils in there.


In this post I take you through a recent calculation to estimate the number of items we have in our micropalaeontology collection, and conclude that understanding how these collection sizes have been estimated is essential in deciding how to manage them.


P1020725_blog.jpgBottles of microfossil residues containing literally uncountable numbers of specimens.


It is relatively easy to make a quick and accurate size calculation for some parts of the microfossil collection. Slides are housed in standard cabinets holding 105 drawers that each hold 55 slides. The 24 standard cabinets in the Heron-Allen Microfossil Library therefore contain roughly 138,600 slides if they are full. By similar calculations, the Former Aberystwyth University Microfossil Collection contains a total of about 60,000 slides and the Former BP Microfossil Collection 300,000.


However, some cabinets are not completely full so we estimated percentage of expansion space and scaled down the figures accordingly. The total number of microfossil slides in the entire collection is estimated to be about 550,000.


But this is an estimate for the number of slides, not specimens. One slide, like the residue bottle, may contain 10s, 100s or even 1000s of specimens. Is it worth counting all of these? Probably not. You'd be there forever. Obviously when calculating the 70 million specimen figure, these vast numbers of additional specimens have not been taken into consideration otherwise the microfossil collection would have accounted for a large percentage of the total 70 million figure and perhaps even surpassed it!



This slide was counted as a single item in our size estimate for the microfossil collection. Each square contains a different species and multiple specimens are present, so these counts could legitimately be added to our total number of specimens for the collection.


It would appear that by counting slides and not the specimens on them, we are making the microfossil collection and hence the Museum collection appear smaller than it is. So does this matter?


This really depends on how you use the information. I think it is fine to give estimated figures like we do on the Museum website as it gives members of the public an idea of the vast size of the collection. On the other hand, if you use these figures to make decisions on how to allocate resources to the collection, then it becomes really important to account for the way in which the data is generated.


It wouldn't be right for example, to decide how much funding to give a museum relative to another one based on figures like these, without knowing how they had been generated. It's probably unwise to take too much notice of website details of the relative sizes of collections at the AMNH, Smithsonian and Natural History Museum, as the data has almost certainly been gathered in a different way by each institution.

PF_70832_Various_Foraminifera_Christmas_1921.jpgAnother slide with multiple specimens that counts for a single item within the 550,000 slides in the microfossil collection. The story behind this slide can be found in my Microfossil Christmas Card post.


If we have 70 million specimens in the Museum, and just over half a million in the microfossil collection, which is looked after by one curator, it would, on average, suggest that we need 140 curators to manage the entire collection. The actual figure is closer to 100. Taking these figures literally would therefore suggest that I am doing well to only have to manage half a million specimens!


Of course it is not that simple. Data derived from other parts of the Museum collection are not comparable. A tray of 100 identical sharks teeth for example would have been counted as 100 individual specimens, whereas the squared microfossil slide shown above would have counted as an individual item. Other parts of the collection might appear to require more management resources, until they are compared on an equal basis by separating out curatorial units sometimes referred to as 'collection lots'. The tray of 100 sharks teeth in this instance would count as one collection lot.


It would be wrong to suggest that collection size estimates are the only factors taken into consideration when deciding how to allocate resources across a vast collection like ours. Monetary value, state of conservation, suitability for display, visitor and loan demand, educational, scientific and historical significance are also taken into account. 


I would say that 70 million is probably an under-estimate of the size of the Museum collection if you take into consideration the 'microfossil factor' of collections where there are simply uncountable numbers of specimens within collection lots. I don't think we will ever come to a meaningful total if we attempt to count individual specimens.


However, it is vital that we are consistent in how we interpret the figures derived from our own collection, especially if we use them to help make decisions on how to manage it in the future. An estimation of the number of lots rather than specimens would help towards this.

Giles Miller

Giles Miller

Member since: Apr 21, 2010

This is Giles Miller's Curator of Micropalaeontology blog. I make the Museum micropalaeontology collections available to visitors from all over the world, publish articles on the collections, give public talks and occasionally make collections myself.

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