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Curator of Micropalaeontology's blog

52 Posts tagged with the palaeontology tag
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I'm so tempted to say that a microfossil curator attends meetings and writes e-mails. Sometimes it feels like that. I decided to document a typical day back in January where e-mails and meetings helped prepare towards a loan for an art exhibition, gave news of a potentially exciting new acquisition and a possible research opportunity involving micro-CT scanning.

 

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One of Irene Kopelman's items in the Gasworks Gallery based on microfossils from our collection

 

The bulk of the e-traffic involves preparations towards an exhibition that opened on 10 Feb at the Gasworks Gallery near the Oval Cricket Ground. Artist Irene Kopelman's work was partly inspired by some slides of radiolarian microfossils from our collections. We are preparing an exhibition loan of the slides and today there is a lot of correspondence discussing arrangements for two open day tours I am holding to accompany the exhibition.

 

Most microfossils are so small that I have to deal with images rather than the specimens themselves. We recently sent some specimens on loan to the Smithsonian Institution in Washington where a researcher has made some images for a publication and left them on an ftp site for me to collect. I am also making arrangements for other images of our specimens to be sent to us by one of our regular visitors. They have posted them on an excellent site for people interested in foraminiferal microfossils.

 

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Aggerostramen rustica, a type of foraminiferal microfossil that builds a shell from sediment. In this case, sponge spicules have been chosen. This image has been posted on-line at the foraminifera.eu site mentioned above

 

Typically a day will not pass without some correspondence with future visitors to the collections and/or an actual visit from a scientist. Two visitors want to come in a couple of days time and another wants to visit the following week to discuss a short paper on a major collection of 2,500 slides that they donated last year.

 

In a few days time I'm off to our collections outstation in Wandsworth to meet OU PhD student Kate Salmon who is using our collections to study ocean acidification. I need to book a Museum vehicle to transport me to Wandsworth and to bring the collections back that she would like to borrow.

 

I mentioned meetings but you'll be glad to know that I'm not going to go into detail here. From one meeting I come away with two additional enquiries to answer; a request by a journalism student for a 5 minute mock radio interview and a student wants images of some of our specimens for their thesis.

 

I am also asked to assess a destructive sampling request as my boss is away. Sometimes our samples or specimens need further analysis to reveal their true scientific potential. In this case the borrower wants to make thin sections of fragments of fish fossils and to carry out 3-D imaging using a synchrotron (see my previous blog on sex in the Cretaceous for details of synchrotrons). The work will potentially give important details about early fish evolution so the request is ratified.

 

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Erasmus student Angelo Mossoni using one of the scanning electron microscopes at the Museum.

 

 

The excellent research facilities here at the Museum offer many exciting possibilities. Today an e-mail has come in requesting bids for use of the micro-CT scanner. I want to test whether this method can provide 3-D images of some tiny specimens the reverse sides of which we cannot analyse at the moment because they are stored embedded in wax. If it works, some 3-D images of some of our most important specimens will be delivered to the web. Some of these species have been used extensively in studies on climate change and oceanography.

 

One message informs me that an exciting new sample has just been sent as a donation from Oman. When it arrives I will need to dissolve some of it in acid (vinegar) to release the tiny fossils. Traces of fish microfossil are clearly visible on the surface of the rock so this sounds very promising and possibly the subject of a new paper on early fish evolution.

 

It would appear from everything listed above that there is not much time for any other activities. However, documenting the collections for the web is one of our core duties so I find time in the afternoon to work towards a documentation project. I am also on duty for an hour to answer questions from my fellow curators and my mentee Jacqui about using the databasing system.

 

A number of people including my two new colleagues Tom and Steve, pop their heads round my door to ask questions about the collections or bring me information. Retired Museum Associate Richard Hodgkinson is in today and has some questions about his project. Another retired member of staff brings me a copy of his latest paper and former volunteer and now colleague Lyndsey Douglas comes to tell me that my blog has been quoted in the January edition of the Museums Journal!

 

It's an amazingly variable job being a microfossil curator and no day is ever the same as another. I love my job and I think of it as unique. I don't know of anyone else in the world who has a similar job in Micropalaeontology. If you have a similar job, I'd love to hear from you.

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The Antarctic is very much the flavour of the month here. To mark the 100th anniversary of Scott reaching the South Pole, a new exhibition opened on 20th Jan at the Museum. The Museum holds over 40,000 items relating to Scott's Terra Nova Expedition of 1910 so I thought I would show you details of one of the treasures that remains hidden from view. A wonderful book of bound documents tells the story of Edward Heron Allen and Arthur Earland's study of the Terra Nova material; how the collection was acquired, studied and the significance of the discoveries that they made.

 

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The start of the letter from Edward W. Nelson to Arthur Earland prior to the expedition.

 

In my microfossil Christmas card post I mentioned that Heron-Allen and Earland had worked on material from Scott's Terra Nova Expedition of 1910. Although they had not been on the trip, a letter from crew member and biologist Edward W Nelson (1883-1923) clearly shows that Earland had been in contact before the trip to encourage Nelson to look out for foraminifera. The exhibition at the Museum has a picture of Nelson along with all of the other crew members and outlines some of the scientific research that went on as part of the expedition as well as the expedition to the South Pole.

 

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Part of the Heron-Allen Type Slide Collection from the Terra Nova Expedition material.

 

The Terra Nova was the ship that carried Scott and his party to the Antarctic and lent its name to the expedition. Samples were collected from the ocean bottom as it travelled from Britain via the Atlantic Ocean to the Antarctic. While in the Antarctic, ocean bottom samples were dredged too, many of which contained the remains of foraminifera. Even while Scott was on his way to and from the South Pole, the Terra Nova was collecting scientific material from Antarctic region.

 

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Heron-Allen's signed personal annotated copy of the 1922 publication with Arthur Earland and part of one of the letters from Sydney Harmer bound next to it.

 

The Keeper of Zoology at the Museum at the time was Dr Sydney Harmer who had worked with Terra Nova expedition member D. G. Lilley to publish a list of the samples and sampling details. The first set of letters are from Harmer inviting Heron-Allen and Earland to work on the material. They clearly state that the authors will not be paid and that the final work will be edited by Harmer himself. Neither of them were ever officially employed by the museum but had an honorary status and were provided room to work at the Museum.

 

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Portraits of Heron-Allen and Earland now hanging in the Museum micropalaeontology library, The Heron-Allen Library.

 

Harmer wrote, 'In a group like the foraminifera I imagine that you would have no difficulty in putting on one side enough duplicates to compensate you in some measure for the trouble of working out the collection.' A later letter states 'I am delighted to have placed it in the hands of an enthusiast to whom no trouble seems too great.' A number of years later, Heron-Allen donated his entire foraminiferal collection to the Museum so all of the original samples, the described material and Heron-Allen's slides are now in our care.

 

This type of information about the acquisition of the collection is very important as it clearly states the agreement between the scientists about how and where the material should be deposited. Heron-Allen was certainly the curator's friend because of the meticulous way he documented and kept relevant archival correspondence and other materials associated with his collections.

 

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Part of one of the illustrations of foraminifera hand drawn by Mary H Brooks.

 

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The receipt for payment for the artwork sent by Mary H. Brooks. It was paid for by Heron-Allen himself.

 

Heron-Allen's copy of the paper is also annotated in red ink with references to slides in the Museum collections. Heron-Allen constructed a series of 'type slides' for all of the samples that he worked on. For the Terra Nova Expedition these were slides showing good examples of each of the foraminiferal species encountered at each collecting station of the expedition. As a result this library volume is an extremely useful reference to researchers looking at Terra Nova collections and is a great example of the value of the library items that accompany the collections here at the Museum.

 

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Details of some of the 'type slides' from the collection. The material in these slides was being collected by the crew of the Terra Nova from Antarctic waters at the time that Scott was attempting to return from the South Pole.

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Some annotations in red made by Heron-Allen that links the published text directly to the 'type slides' illustrated above.

 

650 species of foraminifera are described in the publication with 46 new to science. Many forms previously described from the Arctic were also recognised in the Antarctic and the previous theory of bipolarity that foraminifera evolved independently in the Arctic and Antarctic was discounted. Many isomorphs (species made of silica where previously found examples were calcareous) were also discovered. A letter in French from the famous foraminiferologist Schlumberger discusses this issue and is also bound into the volume.

 

It would appear from the correspondence bound into the book after the annotated copy of the paper that the authors had a great many problems in the editorial stage of their publication. There are many letters between Heron-Allen and Harmer discussing issues about the publication proofs. In one letter, Harmer requests that Heron-Allen cuts down the size of the manuscript by reducing the size of the appendices. The volume ends with a poem written by Heron-Allen that starts:

 

Goodbye old friend our task is over

we bid farewell to the 'Terra Nova'

Henceforth will life be somewhat calmer

For me - 'Eugenie' and Sydney Harmer

 

The 100th anniversary of the tragic demise of Captain Scott quite rightly makes the headlines. However, it should not be forgotten that the Terra Nova Expedition was responsible for many new scientific discoveries. This amazing volume of hidden treasures is testament to Heron-Allen's meticulous record keeping but also to some of the discoveries that are not normally associated with the Terra Nova Expedition. The new exhibition at the Museum strikes a good balance between telling the story of Captain Scott and highlighting the scientific breakthroughs that resulted from the expedition.

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So how do you get a fossil named after you? The easiest way is to make friends with a Palaeontologist who is good at discovering things and is looking for names to call their new finds. A slightly harder way is to find a new fossil species and give it to a Palaeontologist who names it after you.  (In case you were wondering, it is against the rules to call new discoveries after yourself ). Just before ChristmasI had a visit from my old friend Stuart Sutherland from Canada who named a fossil after me back in 1994. I have four fossils named after me and have named some after others too. Here are the stories behind each of them.

 

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On graduation day in 1993; Professor David Siveter, Andrew Swift, Stuart Sutherland and a young looking Giles Miller.

 

Stuart and I were studying for our PhDs at the University of Leicester in the late 1980s and early 1990s. We both had similar field areas in the Welsh Borderland around Ludlow and often scheduled fieldwork for the same time, occasionally helping each other to collect study samples. One summer evening I was helping Stuart to collect samples deep in the Mortimer Forest outside Ludlow. Foolishly I managed to hammer my thumb drawing blood and we had to return to our accomodation early.

 

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Angochitina milleri Sutherland, 1994. This chitinozoan is less than half a millimetre in length.

 

I didn’t realise but Stuart made a note of the sample number and once he dissolved it back in the lab, he found a new species of chitinozoan that he named Angochitina milleri Sutherland, 1994 in my honor. Chitinozoans are tiny organic jug shaped organisms. To this day is it still unclear what they are but they are very useful age diagnostic constituents of marine rocks in the middle Palaeozoic era (very roughly 360-480 Million years ago). Some think that they are some sort of egg case as they sometimes appear linked in chains.

 

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The ostracod Progonocythere milleri Wakefield, 1994 from the Jurassic of Scotland. It is just less than a millimetre long.

 

While Stuart and I were living in Leicester we shared a house with our good friend Matthew Wakefield who was studying ostracods from the Jurassic of the Inner Hebrides, Scotland. He had discovered several new species that he kindly named after his housemates. New species number 2 is therefore Progonocythere milleri Wakefield, 1994. You will notice that after each milleri is the name of the author and the date of publication. I am honoured to have both of these two species named after me and published in Monographs of the Palaeontological Society, a very prestigious journal that has also published Darwin’s work. The holotype of P. milleri also resides in the collections currently in my care.

 

The third milleri is more tenuous as the author, Jonathan Adrain (now University of Iowa) discovered lots of new species of trilobite from the Canadian Arctic while he was working at the Museum. He discovered so many that he decided to use the phone list of the Department of Palaeontology at the time to name his various new species. Hence Gerastos milleri Adrain, 1997. In fact there were not enough names on the list to completely cover all his new discoveries so he decided to name some of them after his favourite pop group, The Beatles. His publications therefore include a macartneyi a harrisoni and a petebesti!

 

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Kannathalepis milleri Marss & Gagnier, 2001, scales from an ancient fish from the Canadian Arctic.


At the time I asked Jonathan if he could provide some spare rock from his trilobite studies so that I could attempt to extract microfossils. Some of these samples contained some fish scales that I passed on to my good friend Dr Tiiu Märss of Tallinn Technical University, Estonia with whom I was working at the time. One of these samples contained some fragments of a new fish hence the fourth new species named after me Kanathalepis milleri Märss and Gagnier, 2001.

 

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Pictures taken on fieldwork with Tiiu in 1995; with Peter Tarrant at Man Brook and taking a sample from under a tree half way up Caer Caradoc, Shropshire.


Tiiu also passed me some samples from the Canadian Arctic from which I discovered some new species of ostracod that I named Beyrichia marssae Miller, Siveter and Williams, 2010 and Platybolbina adraini Miller, Siveter and Williams, 2010 in honour of Tiiu and Jonathan. However, you will notice from the date after these names that it took me a much longer time to publish my new species!

 

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Beyrichia marssae and Platybolbina adraini.


As you can see from the stories above, the naming of species new to science sometimes provides historical information about the lives of scientists, their collections and collaborations. Working at the Museum and being involved in science has meant that I have met a lot of people from all around the world, some of whom have decided to honour me by naming new species after me for various reasons.

 

Sometimes names become superceded when later research shows that they were not really new. Someone may have already described them or they could be a smaller part of something already described. As far as I know all the milleris are still as valid as the friendships gained through working in science. It was lovely to speak to my Estonian colleague Tiiu while working on this post. I see Matt Wakefield regularly at scientific meetings about ostracods. It has also been great to see my old friend Stuart again.

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Microfossil Christmas cards

Posted by Giles Miller Dec 20, 2011

At this time of year it is customary to exchange Christmas cards so I thought I would post some images of some 'Christmas Card' slides from our collections. A slide was exchanged each Christmas between Edward Heron-Allen (1861-1943) and Arthur Earland (1866-1958) until they fell out in about 1933. The circular views are about the size of a thumb print so you an imagine the time it took to create each one by carefully selecting, laying out and sticking down individual foraminiferal microfossils.

 

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The 1912 slide with the initials AE (Arthur Earland) clearly visible as well as the date. Written on the cardboard of the slide is "Xmas 1912 Prosit! AE"

 

Edward Heron-Allen, a Lawyer by profession, had an unpaid position at the British Museum (Natural History) and was allowed a room in which he was able to study the Foraminifera. He was responsible for gathering much of the early microfossil collection as well as a vast library of foraminiferal books which he donated to the museum. They are now housed, along with more recent microfossil library acquisitions in the 'Heron-Allen Library'.

 

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Details of the 1921 slide. On the card surround is written "Greetings from AE Xmas 1921"

 

Arthur Earland and Edward Heron-Allen collaborated for over 25 years, most notably publishing on the Foraminifera of the Antarctic expedition of the Terra Nova (the expedition also known as Scott's Last Expedition). In around 1933 they had a number of misunderstandings and subsequently fell out. These slides and the archives of letters and books in the Heron-Allen Library here at the Museum hide many interesting historical details. The collections are consulted by social historians as well as scientists for that reason.

 

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Details of a slide given to Heron-Allen by Arthur Earland in 1922.

 

Edward Heron-Allen had many interests including violin making! (As a violinist myself I would love to have a go on one of his violins). The web site of the Heron-Allen Society lists his interests: violins, palmistry, Persian texts, Selsey, esoteric fiction and asparagus. More details about Heron-Allen can be found by joining the Heron-Allen Society. I shall be providing more details about Heron-Allen and the the foraminiferal collections via this blog. In the meantime I wish you all a very happy Christmas!

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Ocean acidification is one of the major effects of increased carbon dioxide levels in the atmosphere caused by the burning of fossil fuels (coal, oil, gas). Museum collections of samples from the ocean bottom worldwide are housed at our Wandsworth outstation and are vital to working out how much more acidic the oceans have become since the 19th Century and to helping create models for future changes.

 

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Three bottles of ocean sediment collected in 1891 as part of the H.M.S. Penguin cruise to the Mediterranean

 

Our outstation at Wandsworth holds the Mineralogy Department's Ocean Bottom Sediment Collection. These are sediment samples from many cruises including the first oceanographic voyage the Challenger Expedition of 1872-1876. I mentioned previously that we hold residues including microfossils at South Kensington so why are these bottles of sediment at Wandsworth of interest to micropalaeontologists?

 

Potentially these bottles contain many thousands of microfossils (the ones above mention the foraminferal genus Globigerina) and as a result, they have been of interest for two PhD students studying the effects of ocean acidification on micro-organisms.

 

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Open University PhD student Kate Salmon accessing the Ocean Bottom Sediment Collection at the Museum outstation at Wandsworth. Curator Dave Smith is in the background.

 

Kate Salmon is using mainly foraminiferal microfossils to measure the scale of ocean acidification in the area around Bermuda. To do this she is studying samples collected every 2 weeks for the past 20-30 years in sediment traps on the ocean bottom.

 

The weights and shell thicknesses of these micro-organisms that use the ocean water to produce their shells of calcium carbonate should be different in pre-industrial samples. If ocean acidification is happening we should see lighter more fragile shells in the present day. Kate is using the Ocean Bottom Sediment Collection at the Museum to find comparative material from pre-industrial times.

 

Kate recently told me, 'If I do the same shell analyses on these samples, it will give a good comparison of low carbon dioxide conditions with higher carbon dioxide conditions (present day) and I will be able to see how conditions have changed for the calcifying biology of the oceans. I can then use these results to predict any future changes in the calcification of foraminifera and the implications this will have for other creatures living in the water column'.

 

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Part of the residue collection from the H.M.S. Penguin expedition collected in 1891.

 

Ella Howes, a student at the Laboratoire d'Océanographie de Villefranche sur Mer, France approached us to see if we had any sediment including the remains of tiny organisms called pteropods. These are small planktonic gastropods (floating snails) that have been used extensively in ocean acidification studies. Ella has recent material from near Bear Island in the Mediterranean and wants to compare the composition and structure of these faunas prior to major industrial activity.

 

She is searching for a particular pteropod species Limacina helicina as well as foraminifera. As with Kate Salmon, she is looking to make measurements of shell thickness to assess possible outcomes of ocean acidification between the Mediterranean and colder water areas.

'In Polar regions the cold temperatures allow increased carbon dioxide in water, potentially causing more extreme repercussions for animals living in these areas. A geographical comparison between the effects on ocean acidification on shell thickness in Polar pteropods and the warmer Mediterranean Sea will be undertaken using modern samples of Limacina helicina and old sediment samples provided by the Natural History Museum' says Ella.

 

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Part of one of four rows of cabinets containing the Ocean Bottom Sediment Collection at the Museum.

 

When you consider the quantity of material at our Wandsworth outstation, there is limitless potential for similar studies to be carried out. There are literally millions of micro-organsims from the ocean bottom waiting to be studied. Listings of these collections can be found on the Museum web site. In the meantime, I will wait with interest to hear from Kate and Ella if a trip to Wandsworth can help quantify ocean acidification.

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This week a surplus set of plaster microfossil models were transferred to the Department of Geology, University Leicester UK to help with teaching micropalaeontology to undergraduate students. The two sets of models were made by 19th Century scientists d'Orbigny (1802-1857) and Reuss (1811-1873), who were some of the very earliest micropalaeontologists.

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A set of d'Orbigny models from the Museum collections. Some look a dirty brown colour but in fact this is an original feature to show the difference between models based on modern species (white) and fossil ones (brown). This set was previously mounted for display in the Museum galleries.

 

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A drawer of d'Orbigny models of Foraminifera. (Skaters on the Museum ice rink can be seen in the background)

 

The famous French scientist Alcide d'Orbigny quickly recognised the difficulty in portraying his work on microfossils to a wider audience because of the small size of the specimens. He carved scale models of foraminferal microfossils from limestone and these originals are in the Museum national d'Histoire naturelle in Paris. He used these to create plaster replicas that he sold in sets to accompany his publication of the first classification of the Foraminifera which was first published back in 1821.

 

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A 'Plaster Army' of Reuss & Fric models arranged in rows reminiscent of the 'Terracotta Army'.

 

The second set was made by Vaclav Fric (1839-1916) under the supervision of Anton Reuss who was similarly looking to illustrate his classification of the Foraminifera. For more information about these models and other microfossil models at the Museum there is a publication in the Geological Curator. A paper was recently submitted for publication in a Special Publication of the Geological Society as a contribution to a set of papers on the history of study of the Foraminifera.

 

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Some more Reuss & Fric models. The black spots show the openings or 'foramen' common to and therefore giving rise to the name 'Foraminifera'.

 

If these models are so important, why are we letting them go from the Museum? Firstly we already have three registered sets of these models in our collections (some are illustrated above). One of these three sets is is on the salvage list for the Palaeontology Department. This means that these will be some of the first items to be saved from the building should there be some sort of disaster and it is deemed safe to do so.

 

Secondly, the model sets on their way to the University of Leicester were never formally accessioned into the Museum collections so we are able to send them on without having to deaccession them. They are slightly worn as they have previously been used for teaching micropalaeontology to postgraduate students. Currently there are limited opportunities for postgraduate study of micropalaeontology so it is very good to know that a new course is starting at the University of Birmingham in September 2012.

 

I would argue that sending these models to a university to help inspire a new generation of micropalaeontologists is exactly the sort of use that d'Orbigny and Reuss would have wanted for their models rather than for them to sit in a box in a dusty corner of my office...

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Some of the Museum's most important ostracod specimens were re-examined recently using synchrotron technology. The results published in the journal Science showed that these very delicate but exquisitely preserved fossils gave evidence for reproduction using giant sperm back in the Cretaceous period about 100 million years ago.

 

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A scanning electron microscope of an exceptionally preserved ostracod from Brazil showing details of unusually preserved soft body parts.

 

From images obtained by scanning electron microscope we have known since the 1970s that the Cretaceous ostracod Harbinia micropapillosa was almost identical in body form to modern day examples. Usually ostracods, microscopic crustaceans that inhabit aquatic environments, leave only their calcareous shells in the fossil record. However, these exceptional fossils from Brazil include details of their organic soft body parts not normally fossilised.

 

These specimens were first found by legendary evolutionary biologist Dr Colin Patterson while he was studying the fossil fish from the same rock formation. He passed them to Dr Ray Bate who published them under the name Pattersoncypris. However, some ostracod workers now believe that they should be classified under the name Harbinia which was first described by a Chinese worker in 1959 and therefore takes naming priority.

 

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The European Synchrotron Research Facility (ESRF) at Grenoble in France.

 

In 2007 we had a request by Dr Renate Matzke-Karasz (University of Munich) and a group of co-workers to take our specimens to Grenoble in France to have them analysed in the synchrotron beam ID19. A synchrotron is a giant ring where electrons are accelerated to great speeds and then bent into a circular path by magnets. Strong magents are used which cause the electron beam to deviate and at this point a very bright, intense synchrotron x-ray is emitted. Sometimes synchrotrons are referred to as diamond light sources as a result. These very intense synchrotron x-rays are then focussed into a beam which can be used for analysis at a sub micrometer scale ideal for our microfossils.

 

Some types of modern day ostracods are well known for their use of giant sperm in reproduction. Dr Matzke-Karasz and her co-workers were interested to see if our fossil specimens (Robin Smith thesis collection) contained any evidence for giant sperm or the organs responsible for its production and storage. As the curator of the specimens it was my job to transport them safely to Grenoble and to handle them while they were being analysed. I also took part in the analysis which went on all day and all night for two days. Fortunately we did get some sleep as there were four of us. We took it in turns with two of us analysing the fossils and two analysing the comparative modern specimens in 6 hour shifts.

 

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Positioning the specimen so that it is aligned with the beam. (Don't worry about the scary red lines. The beam was only switched on when we were all safely out of the room!).

 

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Dr Radka Symonova (then at Charles University, Czech Republic), Renate, Dr Paul Tafforeau (ESRF) and Dr Robin Smith (Lake Biwa Museum, Japan) examining some early scans in our experimental cabin home for the two days.

 

The specimens were placed in the beam and then rotated 180 degrees while 1500 x-ray cross sections were taken at regular intervals. These x-ray images were then combined together using specially designed software to produce 3-dimensional images (Holotomographic reconstructions). Although we could immediately see evidence for important internal structures while we were analysing the specimens, a lot of work was still required to produce the final results. The slices that make these 3-dimensional images were analysed for internal structures by Renate and her team back in Germany. Artificial colours were painstakingly added to each slice by hand to show these structures more clearly.

 

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One of the x-ray cross sections of a fossil specimen before it was combined into a 3-dimensional image.

 

The results clearly showed differences between males and females. The males had distinctive tubes in the position where modern day ostracods have  a sperm pump called a Zenker's Organ. The females had inflated sacks in the position where modern day ostracods have sperm receptacles. These are only inflated once they have been impregnated with giant sperm. Our results had shown that this reproductive strategy had been in place more than 100 million years ago.

 

 

Video of a female specimen of Harbinia micropapillosa. The orange sacks are the sperm receptacles.

 

So why is this important? As I showed in the dinosaur exhibition blog item, it is vital to know how organisms reproduce so that you can correctly interpret their fossil record and distribution in modern day environments. Ostracods are often restricted to particular environments and can be useful indicators of changes in climate. This particular ostracod species is common in Cretaceous non-marine sediments offshore Brazil and is therefore of interest to oil exploration companies as a marker for key rock formations.

 

Reproduction with giant sperm is not just restricted to the ostracods as other organisms including fruit flies and some types of frog also use this strategy. The evolutionary significance and history of this type of reproductive strategy is still unclear. What is certain is that specimens in the Museum collections show that this was also happening over 100 million years ago!

 

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Some acrylic palm of the hand sized scale models produced from the 3-D synchrotron scans and used at the "Science Uncovered" event.

 

 

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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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