Fossil Fish blog

Hi all, it has been a busy few months for myself and others working with the fossil fish collections. You may have seen some updates on the @NHM_FossilFish twitter account that I have been away on fieldwork and at a couple of conferences, hopefully I will blog about these soon.

One big event the whole Museum is involved in is happening this Friday, it's Science Uncovered! This is a Europe-wide event and is something nearly all the staff in the Museum are involved in. It is a free event with staff and volunteers talking about their research, favourite specimens and hot science topics. There is even a bar where you can come and talk to us over a drink.

Team Fish will be out in force on the evening.

Flyer and my 'I'm a scientist' badge. Look out for people wearing these during the evening.

Dr Zerina Johanson and her team will be presenting new research on the evolution of the shark dentition, how this was built from individual teeth to form a highly functional feeding unit. Shark dentitions are very diverse, representing a wide range of feeding strategies.

CT scan of the jaw of the shark Squalus acanthias.

We will focus particularly on the sawshark dentition, with 'teeth' along an extended rostrum at the front of the head. These function during feeding (for example, slashing through schools of fish), but are they true teeth? Zerina will be in the Origins and Evolution Zone.

Have you heard of oceans called 'Tethys' and 'Panthalassa'? 

Dr Martha Richter will be explaining how fossil fishes and cephalopods can provide clues about the palaeogeography and salinity of ancient oceans as well as the past connections between continents. She will illustrate this with exceptionally well-preserved fossils from two continents, Africa (Morocco) and South America (Brazil), which range in age from the Early and Late Cretaceous c. 100-90 million years ago.

Excavating fossils in the Crato Formation, Brazil.

Martha will be at Station 8: Oceans between 8:30pm and 10pm, in Marine Reptile Way.

Sharks, how big?

How do we know how big the biggest shark was when it is usually only their teeth that fossilise? Learn how to estimate the size of a shark from just their teeth and handle real specimens from Megalodon, one of the biggest sharks that ever lived, which could have swallowed a human whole. I will also be in the Origins and Evolution Zone.

Myself holding one of the Megalodon teeth.

Please do stop by and say hello to one or all of us. It promises to be a great night I hope to see you there! If you can't make it you can always follow events using the hashtag #SU2014.

As some of you might be aware myself and colleagues are organising an upcoming symposium to celebrate 150 years since the birth of one of the great palaeontologists - Sir Arthur Smith Woodward. Smith Woodward might not be as well known as others but he did a lot for palaeontology, particularly fossil fish.

Sir Arthur Smith Woodward

Smith Woodward was born in Macclesfield on 23rd May1864. He started his long career at the NHM (then the British Museum - Natural History) when he was 18 years old in 1882 in the Geology Department. At this point the NHM had only been opened to the public for 16 months, so there was lots to do.

When he started at the Museum he quickly became involved in fossil exhibitions. Around the same time two large collections of newly acquired fossil fish specimens (containing thousands of specimens) previously belonging to two prolific collectors arrived at the Museum - Sir Philip Grey Egerton and William Willoughby Cole, (the 3^rd Earl of Enniskillen). Smith Woodward realised how important these collections were and there were likely to be lots of new species and interesting specimens.

During his time Smith Woodward named over 300 different species of fossil fish and perhaps what he is best known for amongst fossil fish workers is a four part Catalogue of the Fossil Fishes in the British Museum (Natural History) published between 1989 and 1901. This was and remains a very important reference for fossil fish workers. I often refer to the Catalogue on a weekly basis for information about specimens. He also published on fishes from Wealden, Purbeck and the Chalk. Much of his work helped to form the foundations of current research on numerous fish groups.

The Catalogue of Fossil Fishes, written by Sir Arthur Smith Woodward

Smith Woodward became Keeper of Geology in 1901 and spent his entire career here at the Museum, retiring in 1924 when he was knighted! He died in 1944. Over his lifetime he received many awards and medals including being made a fellow of the Royal Society in 1901 and the Lyell and Wollaston Medals of the Geological Society (there are actually too many to name here).

During the symposium we will have several talks about who he was as a person, his contribution to science and how his work has inspired generations of palaeontologists. There will also be poster contributions and a rare chance to see some of his type material described in the Catalogue and other key publications along with some of his many medals, which are kindly on loan to us from the British Museum.

The meeting will take place on Wednesday 21st May in The Flett Events Theatre of the Natural History Museum. Places are still available if you are interested and it is free to attend. However, you must register via the website.

Watch out for further posts about Smith Woodward and how the symposium went. We will also be working to produce a Procedings with a wide cross-section of papers next year. On the day I will be encouraging delegates to tweet and I will be doing the same from the Fossil Fish account and using the hashtag #ASW150.

Our snazzy logo for the symposium

Our last day in the field was one our Ore Curator, Helena Toman, was particulary looking forward to. We had finished visiting the fossil sites and today we would spend having a look around an active mine and collecting samples for the Museum's collections.

Helena tells us more about it...

Before we delve into the world of ores, it’s probably best to clarify what an ore actually is! An ore is any naturally-occurring mineral or assemblage of minerals from which economically important constituents, particularly metals, can be extracted. The field of economic geology focuses on ore deposit formation, ore mineral exploration and the successful extraction and processing of an ore. I like to think of economic geology as occupying one of those crucial interfaces between science and society and so one of the challenges as the Ore Collections Curator is to make the science accessible to society.

Over the past couple of months, you’ve taken part in our adventure to the geological treasure trove that is Morocco. After sieving for Cretaceous sharks teeth; excavating extinct volcanoes for mantle xenoliths and exploring for minerals we reach the final field stop of this incredible journey, the cobalt-nickel arsenide ore bodies of Bou-Azzer.

On the road into Bou-Azzer mine.

Looking over the mine.

Located in the central Anti-Atlas Mountain range within a very old (788 ± 9 Ma, Gahlan et al., 2006) ophiolite – a section of the ancient sea floor that has been obducted onto land - Bou-Azzer is presently the only mining district in the world to produce cobalt as a primary commodity from arsenide ores (USGS, 2011).  As cobalt is usually extracted as a by-product, mineralisation at Bou-Azzer is unusual and therefore scientifically interesting. Put bluntly, we’d be mad not to visit and collect!

One thing that you can safely predict is that most mining operations are located in very remote and difficult-to-access locations. Bou-Azzer is no exception. After a long, bumpy, but visually stunning car ride we were warmly welcomed by mine employees who introduced the group to the geology and mining history of the district. Then, after a much needed sugary mint tea, the moment had arrived. The moment I had been waiting for – access to the ore pile! We drove up. The midday sun beat down on the mass pile of rocks before us.

Looking through the discarded material next to the mine.

Dull silvers highlighted the primary cobalt mineralisation of Bou-Azzer: skutterudite (CoAs_3­); safflorite (CoAs₂); loellingite (FeAs_2­); nickeline (NiAs) and rammelsbergite (NiAs₂) while pale pinks and rich purples drew attention to the secondary mineral, erythrite (Co₃[AsO₄]₂.8H₂O) (Ahmed et al., 2009). I have to admit, as ores go, they rarely get ‘prettier’.

Some of the samples we collected at the mine.

While I could have stayed for days, our schedule was very tight and it wasn’t long before we needed to leave; it really was a case of ‘all hands on deck!’ Decision making (often against the clock) is part of a curator’s in-field skill set, so only samples that best provided an understanding of the mineralogy, mineral assemblages, mineral textures and mineralisation styles present at Bou-Azzer, made it into the suite.

Primary cobalt ore.

Primary cobalt ore.

Secondary erythrite.

This suite (of 30 hand samples) was collected with two purposes in mind:

     1) collection enhancement of the existing Natural History Museum ore collection

     2) to serve as material for research initiatives investigating cobalt as a ‘critical element’

As someone whose scientific interest area is economic geology, visiting Bou-Azzer was the cherry on top of the cake – or, as we are dealing with all things Moroccan, the mint in my tea. Describe the fieldtrip in one word? Ore-some.

If you would like to find out more about ores, the Museum ore collection and our research, please see our ores group webpages, or you can follow up with the references below.

Thank you to Helena for telling us more about the ores and what we collected.

I was particularly excited about going to the mine as we were trying to find some pink minerals, and pink is my favourite colour. Some of the specimens looked wonderful sparkling in the sun and it was great that we were able to collect so many new samples for the ore collections.

I thoroughly enjoyed my time in Morocco, seeing something new every day and you can learn so much more in the field than reading a book or paper about the area. For me, it was great to learn from the mineralogists on the trip and find out more about what they do and also learn from more senior members of staff (I think we all enjoyed learning from each other and getting to know each other better).

Being able to visit sites I have heard so much about such as the Kem Kem and Goulmima was fantastic. And knowing that finding the fossils (and mineral specimens) during our trip helped to enhance the Museum collections is a great feeling. I am hoping to return to Morocco later in the year to present some results at a conference of specimens we collected during our trip.

References

Ahmad, A.H., Arai, Shoji, and Ikenne, Moha, 2009, Mineralogy and paragenesis of the Co-Ni arsenide ores of Bou Azzer, Anti-Atlas, Morocco: Economic Geology, v. 104, no. 2, March–April, p. 249–266.

USGS, 2011, Minerals Yearbook: Morocco and Western Sahara (Advanced Release), p. 30.1 – 30.9.

Gahlan, H., Arai, S., Ahmed, A.H., Ishida, Y., Abdel-Aziz, Y.M., and Rahimi, A., 2006, Origin of magnetite veins in serpentinite from the Late Proterozoic Bou-Azzer ophiolite, Anti-Atlas, Morocco: An implication for mobility of iron during serpentinization: Journal of African Earth Sciences, v. 46, p.318–330.