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Curator of Micropalaeontology's blog

6 Posts tagged with the radiolarian tag

The quick answer to this is no. If you read my post on who visits our collections and why? you will see that we host visits to the microfossil collections from local amateur groups, artists and very occasionally historians. One of my visitors last week, artist Jennifer Mitchell seemed genuinely surprised that we so readily open the door to visitors who are not scientists in professional positions, or university students. This post investigates how she found us and whether we do enough to encourage visits from non-scientists.


Haeckel and the radiolarians


Jennifer was enquiring about the historical collections of famous evolutionary biologist Ernst Haeckel (1834-1919) and in particular material collected on the H.M.S. Challenger Expedition of 1872-1876. Haeckel published some amazing illustrations of marine life including illustrations of the microscopic radiolarians. Haeckel's work inspired the famous father and son Leopold and Rudolf Blaschka to create glass models of radiolarians, examples of which can been seen in our Treasures Gallery. Jennifer wanted to see the original material from which Haeckel's illustrations were created.


Eucyrtidium_Haeckel_Plate.jpgSome artwork from a monograph published in 1862 by Ernst Haeckel on the radiolarians, alongside a Blaschka glass model of a radiolarian inspired by Haeckel's work and displayed (on rotation) in our Treasures Gallery.


I was interested to hear how Jennifer knew to contact me to arrange access. Her initial enquiry came via the Museum Archives web pages. The archivist responded that Jennifer needed to contact my colleague Miranda Lowe in Life Sciences and Miranda passed the enquiry to me when she realised that it related to our microfossil collections.



One of the Ernst Haeckel slides that Jennifer Mitchell viewed during her visit. Haeckel created sets of slides that he sold to various museums including the British Museum of Natural History.


Less than 5% of our enquiries about the microfossil collections come via the Museum website, where there is a link to a general enquiries e-mail. This general email then gets forwarded to the relevant curator or researcher for them to deal with. The vast majority of the enquiries I get are direct from people that have had some prior connection with me or the Museum.


Does this mean that people find it difficult to know who to contact and are therefore put off enquiring about our collections? Jennifer's example suggests that this might be the case, although she did finally find the relevant person via several emails.


Let's digitise


Are we doing enough to let people know about our behind the scenes collections? Our website gives some details but the vast majority of our microfossil collections are not findable via a search facility on our site because they are not computer registered. Mainly visitors know of our collections because of the publications that cite them.


The Museum is engaging in a major digitisation project aimed at digitising 20 million of our specimens in the next 5 years. This will almost certainly help, but my experience of delivering collections information to the web is that you still need to keep telling the relevant audiences that you can search for specimens on our site by advertising the URL.



This is what Haeckel saw down the microscope. It's amazing to see the material he used to create the illustrations in his famous monographs. Even with modern microscopes the depth of field issue means that the specimens are never all in focus at once hence the blurry nature of this image.


Would we get more enquiries if we more proactively advertised contact details and that we facilitate access to our behind the scenes collections to a wider audience by appointment? Almost certainly we would. I see it as an important part of my role to make people aware that our collections are here to be used by whoever wants to use them. This was the over-riding reason for me in starting this blog.


However, hosting an increased number of visits and maintaining visitor facilities is a major drain on resources such as staff time. I firmly believe that it is our duty to make these collections available to everyone, but it does come at a cost.


A wider reach with limited resources?


Some of my colleagues in charge of popular and high profile parts of our collection host a constant string of visitors, so advertising to a wider audience would not be appropriate because resources are not available to cope with increased visitor numbers. I would argue that the Museum galleries allow access to a wider audience for these types of collection (e.g. dinosaurs, meteorites, early humans, mammoths).


For the microfossil collections, where we have virtually nothing on display, it is a balancing act between advertising to promote access and encouraging so many visitors that we don't have the resources to deal with them.


So our collections are available to a wider audience beyond professional scientists and students, but I would argue that we could do more to advertise our microfossil collection to all audiences by appointment. Jennifer suggested 'to be able to contact the curator or appropriate person directly from the website and let them deal with the request directly would be more efficient for everyone especially the curators'.


It will be really interesting to see how enquiries access is handled when the current project to revamp our Museum website is finished. I'd also love to hear any opinions on access to behind the scenes collections, particularly if you have ever tried to find out about and arrange a visit to our microfossil collections.


Search our digitised microfossil collections


Last year our 100-year-old microfossil Christmas cards were featured in The Independent newspaper and on the Science Focus website. On 30 December I am presenting a Nature Live on the microfossil Christmas cards at 12.30 and 14.30 so if you are in the area, please do pop in and say hello.


If you don't live near London then follow us on @NHM_Micropalaeo as we are tweeting an image of one of our beautiful Christmas microfossil slides each day of December until Christmas.


This year, the Museum has decided to follow a microfossil theme with its own e-Christmas card featuring the Blaschka radiolarian that is currently on display in the Treasures Gallery. To read more see my post about putting radiolarians on display.



The Museum 2013 e-Christmas card



The Blaschka radiolarian model of Hexacontium asteracanthion currently featured in the Treasures Gallery, otherwise affectionately known as 'the red one', is magnified about 500 times. A CT-scan image of this has also appeared on the cover of the NHM Science Review 2011-2012.


Finally I would like to thank all my readers for their support over the past year and wish you all a very merry Christmas and happy new year!


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...


The new Treasures Cadogan Gallery opened at the Museum this week with an iconic specimen from the micropalaeontology collections displayed prominently in the first case you come to when entering from the left-hand-door. Just over 10 years ago, this beautiful glass model of a radiolarian made in Dresden in 1889 by father and son Leopold and Rudolf Blaschka, was housed in a cardboard box and hidden behind the scenes at the Museum.


Treasures Gallery-040-231112_blog.jpg

Picture courtesy of the NHM Picture Library

Radiolarians are single celled organisms (Protozoa) that secrete tiny skeletons of opaline silica or glass so it is appropriate that the Blaschkas should re-create them in glass. They range in size from 0.03mm to 2mm and mainly have a marine solitary floating lifestyle (planktonic), although some are colonial. The model on display is enlarged approximately 1,000 times.


For some time it has been a goal to get the Museum collection of Blaschka models on permanent display so walking into the new gallery this week and seeing the Blaschka specimens finally on show was very exciting. It has been a great team effort enhancing the profile of the collection by research, publications, conference presentations, conservation, exhibition loans, CT-scanning, filming and exhibition design. Here are a series of pictures illustrating the journey of a small part of the Museum Blaschka collection from cardboard box to permanent display.


Raphidiophrys_elegans_1889_6_11_1-18k_Conservation 006_blog.jpg


We hardly dared open the cardboard boxes housing the collection of 18 radiolarians to show them to visitors for fear of breaking the glass models inside. The boxes had "S" written on the side in red to signify that they are salvage specimens to be removed from the Museum first, in the event of a disaster.


To me these glass models are real treasures, not only because of the amazing skill and artistry in their fabrication but also because they so beautifully display aspects of microscopic collections that lie hidden behind the scenes at the Museum. The radiolarian represents the only specimen from the micropalaeontology collections currently on display in the Museum galleries. The octopus and jellyfish also on display show colours and structures that are not visible in spirit collection jars and beautifully show the anatomy of each species.




The Museum holds 185 Blaschka glass models of radiolarians, amoebas, heliozoans (similar to radiolarians), squid, octopuses, cuttlefish, nautiluses, nudibranchs (soft bodied marine molluscs), corals, sea anemones and jellyfishes. The Museum collection was acquired in four stages in 1866, 1876, 1883 and 1889, representing some of the earliest and last marine invertebrates made by the Blaschkas. In 1887 they started making glass flowers for Harvard University and shortly afterwards were employed exclusively by Harvard so ceased making marine invertebrates.


Long serving members of staff recall the collection being on display in the corridor outside the current Human Biology Exhibition in the 1970s. The collection was subsequently divided between the Palaeontology and Zoology departments where it was housed in five different locations throughout the Earth and Life Science departments. Zoology curator Miranda Lowe and I first located the specimens and searched the Museum archives and Zoology specimen registers for details.


Copy of CNV00023.JPG

This image shows a list made by the Blaschkas in 1883 of the models sent to the British Museum including the octopus model on display in the Treasures Cadogan Gallery. The price (113 Reichsmarks) and relatively small size of the transport box (26 x 22 x 15 inches) are shown.
Image courtesy of the Rakow Reserach Library, Corning Museum of Glass, New York (CMGL Bib 94604.6).


Miranda and I made trips to the Blaschka archive in the Rakow Library at the Corning Museum of Glass, New York, to find out more about the history of our collections. These suggest that British Museum staff may have ordered glass taxidermy eyes from the Blaschkas in 1872 and complained when the mollusc models arrived broken in 1883.


The Corning archive also includes the original drawings from which the Blaschkas worked. They gained their inspiration by direct observation from nature and from illustrations in publications like Henry Gosse's 1860 Actinologia britannica or Ernst Haeckel's 1862 monograph on the Radiolaria (see above). The publication by Haeckel was one of the first to employ evolutionary theory to explain the distribution of organisms so it is appropriate that a copy of Darwin's On the Origin of Species is displayed next to the Blaschka models in the Treasures Cadogan Gallery.



The National Museum of Ireland copy of the radiolarian Aulosphaera elegantissima now appears on each cover of the journal Historical Biology. Reproduced with permission from Nigel Monaghan (National Museum of Ireland) and Taylor and Francis.


Blaschka experts met at a conference in Dublin in 2007 made possible by the kind benefaction of George Loudon with the support of the National Museum of Ireland. Miranda and I presented a paper on the Museum Blaschka Collection that was published the following year in the Blaschka conference proceedings.



At the time of the conference the profile of the Museum Blaschka collection had been raised both in and outside the Museum leading to several requests from other museums to display our Blaschka models in temporary exhibitions. Models were lent to the National Glass Centre in Sunderland, Sheffield Museum and displayed in temporary exhibitions at the Museum at Tring (see above) and in The Deep here at South Kensington.




Transport boxes for Blaschka models at the National Glass Centre, Sunderland. In case you were wondering, they were empty when this picture was taken. We wouldn't dream of stacking them like this if they were full!


Special cases were bought so that the models could be transported safely to and from exhibition venues. Bespoke inserts were made from layers of Plastazote™ foam and white Tyvek™ cloth to hold the items firmly in place during transport. These boxes were then transported in lorries usually employed for moving works of art between galleries.


Meanwhile, new conservation grade storage boxes for the collection were constructed initially by Felicity Bolton, then of the Museum's Palaeontology Conservation Unit. For her published work on the displayed radiolarian model, Liesa Brierley was awarded the Institute of Conservation’s Nigel Williams Prize for glass and ceramics conservation as well as a prize for the best student dissertation of 2008 at the University of Applied Sciences Erfurt, Germany.


She employed a two-stage cleaning process using a modified museum vacuum and a range of soft brushes followed by a mixture of solvents on an antistatic mini swab. She also reattached broken spines with reversible adhesive Paraloid™ B72, remounted some of the fine model strands using nylon micro-tubing and carried out initial CT-scanning of some of the models.


CT_model.jpgCT-scan of the gold centre of the displayed radiolarian not seen since the Blaschkas made the model in 1889.


Chris Collins and Effie Verventiotou of the Museum Conservation Centre in conjunction with Dr Farah Ahmed in the Museum's Imaging and Analysis Centre employed CT-scanning as well as other detailed analytical techniques to study the condition of the models. This has revealed valuable information about how the models were built, helping conservators to better understand deterioration processes and to tailor their conservation strategies.


Effie, who carried out the conservation work on the octopus and jellyfish models, remarked about the octopus, "The results of the study showed the use of animal glue and gum arabic used as coatings, adhesives and paint media. The analysis also demonstrated the use of at least two different types of glass on its construction and revealed an intricate internal structure."



Helen Walker with Effie Verventiotou and Miranda Lowe at the installation of the Blaschka case of the Treasures Cadogan Gallery.


In conjunction with museun mount maker specialist Helen Walker from the Design and Conservation Department, Effie also used these CT-scans to print 3-D mounts for the displayed specimens so that the bases of the radiolarian and octopus specimens could be perfectly supported while on display.


Light levels in the gallery are kept to a minimum and the models will be changed every 6 months to avoid light damage. The mounts are attached to granite blocks and the glass cases fixed to the underlying structure of the museum building rather than resting directly on the floorboards of the gallery to minimise the possibility of vibration damage.




Getting just three of the Museum Blaschka collection items from their cardboard boxes to permanent display has been a major undertaking involving a very large team. I just checked my Blaschka e-mail folder and it includes over 2,500 e-mails sent over 10 years by over 100 different people so apologies that I have failed to mention everyone involved.


I must have opened the Blaschka cabinet for visitors, tours and various Museum staff hundreds of times during these 10 years so I am delighted that the Museum chose and supported the work for Blaschka specimens to be part of the new gallery and available for all to see in future. Several on-line resources are available including a Treasures video on the BBC website, details of all Treasures specimens in the gallery a short Blaschka film featuring Miranda, Effie, Farah and myself (the YouTube version is also embedded below). The radiolarian and all the other Treasures in the gallery look amazing on-line but even more spectacular in real life so please visit if you can.



The Treasures Cadogan Gallery is free and open every day of the year apart from Christmas Day. As you leave, don't forget to vote for the Blaschka models as your favourite on the interactive screen situated to the left of Guy the Gorilla.


The Museum radiolarian collection makes up considerably less than 1% of the total microfossil collection but is proving very popular at the moment. Last February we loaned some slides to accompany an exhibition by Irene Kopelman at the Gasworks Gallery and this week I processed a loan for Artist/PhD Researcher Gemma Anderson. Glass models of radiolarians made in 1889 by the father and son partnership of Leopold and Rudolf Blaschka are also being prepared for something special that will be happening later in the year at the Museum.



A scanning electron microscope image of part of the fossil radiolarian residue on loan to Gemma Anderson. The tip of a standard 0.65mm diameter dressmaking pin is included for scale.


Radiolarians are single celled organisms (Protozoa) that secrete tiny skeletons of opaline silica. They are present in the oceans of today from the tropics to the Arctic and live anywhere from near the surface to depths of several hundred metres. They range in size from 0.03mm to 2mm and mainly have a solitary floating lifestyle (planktonic), although some are colonial.


The living cell that produces the skeleton consists of a central mass of cytoplasm surrounded by a peripheral layer called the extracapsulum. Sometimes the extracapsulum contains bubble like structures that aid flotation and occasionally algal symbionts. The cells also produce radiating fine structures called axopodia. In some species these are contractile and may have been used to move organic particles closer to the extracapsulum for digestion.


Fine strands called fusules connect the extracapsulum with the inner capsule and these are unique to the Radiolaria. Modern radiolarians are subdivided based on the microanatomy of the central capsule whereas fossil forms are classified on skeletal characteristics. The living and fossil classification schemes are not intergrated as a result.



A Blaschka glass model of the radiolarian Aulosphaera elegantissima Haeckel, 1862. The central mass of cytoplasm, the axiopoda and the spherical silica shell are magnified about 500 times and reproduced in glass.


A collection of 18 radiolarian and heliozoan Blaschka glass models were acquired by the Museum in 1889. The Blaschkas made 10 different varieties of Radiolaria representing two of the three main subdivisions. They also offered three varieties of Heliozoa (literally sun animals). These look superficially like radiolarians but differ in the arrangement of the pseudo/axo-podia and the cellular structure in the central capsulum.


The illustration of A. elegantissima in Ernst Haeckel's 1862 monograph on the Radiolaria that provded the inspiration for their work.


Radiolarians are very beautiful to look at but are also scientifically significant. The have a long geological record stretching back more than 500 million years to the Cambrian Period. This makes them very useful for determining the age of sedimentary rocks that contain them as well as giving details of past climates and oceanographic conditions.


The Museum's radiolarian collection of 1,500 slides is small but historically very significant. Ernst Haeckel described 2,775 new radiolarian species in his 1887 monograph on the Challenger radiolarians [PDF] but did not define any type specimens. A set of teaching slides made by Haeckel in the Museum collection is the only set of plankton slides available from the Challenger Expedition. Residues in the Ocean Bottom Sediment Collection also contain important comparative specimens that help define Haeckel's species concepts in the absense of type specimens.




A close up of part of the radiolarian residue on loan to Gemma Anderson. It is from Miocene Barbados Marl which is roughly 15 million years old.


It will be very interesting to see the results of Gemma's study; I will comment on this blog with any details. I would also be very excited to see a Blaschka radiolarian model on display in the Museum galleries. I promise a more detailed post on the Museum Blaschka Collection in the future with a very interesting story involving a team of archivists, curators, conservators and exhibition staff (with some C-T scanning too).


Irene Kopelman's exhibition entitled "The Challengers Report" opened on 10 Feb at the Gasworks Gallery and features artwork inspired by a visit to the micropalaeontology collections at the Museum. The glass slides of Antarctic radiolarian specimens used by Irene have been loaned for display as part of the exhibition, and two tours of the micropalaeontology collections were provided just after the exhibition opened.



Irene Kopelman in front of two of her acrylic on canvas works based on Radiolaria. Pelham Miller makes a guest appearance in the picture on part of his rapid tour of the gallery!


Irene's work borrows patterns from nature or techniques of observation and classification from the history of science. Her inspirations include the expeditions of renowned explorers such as Scott and Shackleton; the title of the exhibition refers to the Challenger Expedition of 1872-76 which laid the foundations for modern oceanography. The exhibition includes large scale paintings of Antarctic radiolarians (see two of them above).



Gasworks Curator Robert Leckie demonstrating the display of slides loaned by the Museum.


The slides loaned were transported in a purpose built carrying box made by Palaeontology Department Loans Officer Noemi Moran Lorengo from Plastazote inert foam. Noemi also processed the reams of paperwork associated with the loan and carried out a condition survey of the slides prior to their transport.



The purpose built carrying case made from Plastazote and conservation grade card by Noemi (photo provided by Noemi Moran Lorengo).


The slides of Antarctic radiolarians loaned to the exhibition (photo provided by Noemi Moran Lorengo). The specimens themselves are less than half a millimetre in size and are encased in Canada balsam that has turned brown in the roughly hundred years since the slides were created.


Two tours of the micropalaeontology collections were also included in the Gasworks events associated with the exhibition. We were able to showcase some of the amazing artwork associated with our collections including the 1889 Blaschka radiolarian models created from glass. Other materials included specimens and documents on an Antarctic theme including Heron-Allen's bound Terra Nova study volume and some radiolarian slides from the same expedition.



Demonstrating slides and artwork as part of one of the two tours to the Micropalaeontology Collections (photo courtesy of Robert Leckie).


It was great to be able to visit the opening of the exhibition with my family - our daughter Blossom was born shortly before Irene first came to the Museum.


My thanks go to Lil Stevens who pointed Irene in the direction of this material while I was on paternity leave. We are hoping that Irene can come again in March and we can maintain links with artists from Gasworks following the Museum tours.

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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