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The intention of the blog is to have discussions on any topic relating to the work of the Museum. I hope you will find time to make your inputs. Please visit it and make your contributions about what you like or dislike about museums, why you visit or use museum, et cetera.

Surreal 360 million year old spiky armoured fishes reconstructed for the first time

posted 11 Apr 2017, 06:49 by Linda Dyani

Africanaspis is a genus of armour plated (placoderm) fish, only known from the Late Devonian (360 million year old) Waterloo Farm lagerstätten of South Africa.  It was first named, in 1997, on the basis of isolated plates representing only three of the trunk armour plates, of a single species (Africanaspis doryssa).

Ongoing excavation of shale rescued from Waterloo Farm, by Dr Rob Gess, who found the original material, has since then produced far more complete material. In a paper published in PLOS One on 5th April 2017, by Dr Rob Gess of the Albany Museum and Rhodes University and Professor Kate Trinajstic of Curtin University, reconstructions of the entire head and body armour of this extraordinary fish are revealed. Incredibly though that’s not where it ends – in several specimens there are also compressions preserved of the unarmoured tails that protruded behind the armoured body. This soft unarmoured portion of the body is completely unknown in the vast majority of armour plated fish.

The authors furthermore reveal that a second, more robust species which they named Africanaspis edmountaini  also inhabited the Waterloo Farm lagerstätten lagoon.

Specimens represent fish of a range of sizes. Although adult Africanaspis doryssa were between 20 and 30 centimetres long, one minute specimen was less than 3 centimetres long. Its large eyes suggest that it was newly hatched or born. This range of sizes indicate that Africanaspis  spent its entire life around the coastal lagoonal lake that is represented at Waterloo Farm. This differs from the lifestyle of coelacanths previously described from the same site, which are only known from juveniles, indicating that they used the ancient estuary exclusively as a breeding nursery.

 

Link to paper online:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0173169

280 million-year-old fossil reveals origins of chimaeroid fishes

posted 27 Feb 2017, 04:10 by Linda Dyani

Discovery allows scientists to connect the last major vertebrate group to the tree of life

 

High-definition CT scans of the fossilized skull of a 280 million-year-old fish reveal the origin of chimaeras, a group of cartilaginous fish related to sharks. Analysis of the brain case of Dwykaselachus oosthuizeni, a shark-like fossil from South Africa, shows telltale structures of the brain, major cranial nerves, nostrils and inner ear belonging to modern-day chimaeras.

 

This discovery, published early online in Nature on Jan. 4, allows scientists to firmly anchor chimaeroids—the last major surviving vertebrate group to be properly situated on the tree of life—in evolutionary history, and sheds light on the early development of these fish as they diverged from their deep, shared ancestry with sharks.

 

“The origin of holocephalan fish (chimaeras) has long puzzled scientists, who had worked out the evolutionary relationships of all other major living vertebrate groups. Chimaeras were clearly somehow related to sharks and rays but they are very different, with a very distinctive skull. All fossil chimaeras were already completely chimaera so they were no recognised in-between forms to bridge the gap between their ancestors and the ancestors of modern sharks. Our research demonstrates that Dwykaselachus provides the missing piece of the puzzle, as it has features of certain primitive ‘sharks’ as well as of chimaeras. We can now anchor chimaeras firmly on the tree of vertebrate life.” According to Dr Rob Gess, a co-author on the study and currently a South African CoE in Palaeosciences partner, based at the Albany Museum in Grahamstown.

 

There are about 50 living species of chimaeras, known in South Africa as Josef, St. Joseph sharks or elephant sharks. They represent one of four fundamental divisions of modern vertebrate biodiversity and are actually very different from sharks – with large eyes and tooth plates adapted for grinding prey. St Joseph sharks generally live very deep in the ocean, but come into shallower waters to breed in summer. As a result they are often caught in summer as bicatch and are also sometimes deliberately netted on the west coast of the Western Cape. Their meat is however rather oily and they are not a popular dish.

 “Sharks and chimaeras both have skeletons of cartilage so, other than teeth and fin support spines, fossils of both groups are very rare. None of these had previously shown a combination of characters of both groups,” according to Dr Gess.

 The Dwykaselachus fossil resolves this issue. It was originally discovered by amateur paleontologist and farmer Roy Oosthuizen in the 1980s. Roy Oosthuizen discovered the fossil on his farm, Zwartskraal in the Prince Albert district. He was out in the veld with his son one day when he found the nodule of rock that had weathered out of 280 million year old mudstone, just 30 centimetres above the top of the Dwyka glacial deposits. Thinking that it might contain a fossil he asked his son to hold it edge on whilst he hit it with a hammer. It split into 3 pieces, revealing parts of the fossil skull. It was named by palaeontologist Burger Oelofsen in the eighties. The fossil cartilage is however very thin and couldn’t be excavated out of the rock, so he could only describe what was visible on the broken surfaces of the nodule. The most important features of the fossil weren’t accessible at the time.  After that it was archived in a small cardboard box in the strongroom reserved for type specimens at the South African Museum in Cape Town.

 There it remained until 2013 when Wits’ Evolutionary Studies Institute obtained a micro-CT scanner. “At the time I was a South African CoE in Palaeosciences partner at Rhodes University Geology Department,” recalls Dr Gess. “I immediately requested permission to try scanning some early shark fossils. Initially my main focus was some mid Devonian (420 – 360 million year old) specimens from the Klein Karoo, Mike Coates, suggested that I should include Early Permian  Dwykaselachus in my study. I obtained permission from Iziko Museums to loan it from the South African Museum in Cape. From there I took it up to Wits and we spent days getting the best possible scans. It scanned incredibly well, so our team were able to create a perfect 3D digital image of the skull, inside and out”.      

 At the surface, Dwykaselachus appeared to be a symmoriid shark, a bizarre group of 300+ million-year-old sharks, known for their unusual dorsal fin spines, some resembling boom-like prongs and others surreal ironing boards.

 CT scans showed that the Dwykaselachus skull was remarkably intact, one of very few early cartilaginous skulls that had not been crushed during fossilization. The scans also provide an unprecedented view of the interior of the brain case.

 “When I saw it for the first time, I was stunned. The specimen is remarkable.” Recalls Dr Mike Coates, the paper’s lead author and Professor of Organismal Biology and Anatomy at the University of Chicago.

 They show a series of telltale anatomical structures that mark the specimen as an early chimaera, not a shark. The braincase preserves details about the brain shape, the paths of major cranial nerves and the anatomy of the inner ear. All of which indicate that Dwyka belongs to modern-day chimaeras. The scans reveal clues about how these fish began to diverge from their common ancestry with sharks.

The study, “A symmoriiform chondrichthyan braincase and the origin of chimaeroid fishes,” was supported by the National Science Foundation, the National Research Foundation (NRF) / Department of Science and Technology South African Centre of Excellence in Palaeosciences, and the NRF African Origins Programme. Dr Gess was further supported by Rhodes University Post doctoral bursary. Additional authors include John Finarelli from the University College Dublin, Ireland, and Katharine Criswell and Kristen Tietjen from the University of Chicago

 

 

My journey into the Biodiversity Sector has begun!

posted 27 Feb 2017, 03:03 by Linda Dyani

By Someleze Mgcuwa

Lao Tzu once said that “A journey of a thousand miles begins with one step”. In June 2013 I took that first step, without even knowing that it’s a step in a right direction, It has become a norm in my community for young people to seek employment after Matric due to lack of funds to further our education. When I was presented with the Groen Sebenza (SANBI initiative) opportunity, I saw it as an employment at first, I didn’t even think twice in accepting it as such opportunities are very rare neither to be found nor to reach the rural communities. The term “Biodiversity” was very new to me, but this didn’t pull me back I was eager to learn all about it and see it what actually entails.  I started off by collecting biodiversity specimens ranging from plants, spiders to insects, each of these required that we undergo a training first as it was all new stuff to us; learning the terminology used in each of these organisms we had to collect was a challenge, but my determination and hard work paid off!  My well pinned and mounted insects specimens, as well as plant specimens filed at the Schonland Herbarium are the reminders of how hard work can pay one off.

That was my first step, it didn’t happen overnight as one would think a step will do, there were so many ups and downs. As I continued walking I remembered that a journey to success doesn’t end with a road block, one has to continue walking even if the going gets tougher.

At the beginning of last year I took another step, moving from Pirie Mission (my village) to the “City of Saints” Grahamstown, where I was working as Herbarium Assistant at the Selmar Schonland Herbarium and a CREW (Custodians of Rare and Endangered Wildflowers) field Project Assistant. As a herbarium assistant I was mounting, filling and identifying specimens. For the CREW Eastern Cape Node I was assisting during the field trips by preparing field equipment prior to the trip, data collection and capturing as well as designing identification guides for the volunteers to search for threatened plant species in their respective areas.

My Groen Sebenza contract was going to expire, by the end of November 2015, but Botanical Society of South Africa (BotSoc) extended this journey to another one year and five months. In September 2016 a better opportunity knocks at my door and I opened the door to become a Herbarium Digitizer for Karoo BioGaps for SANBI (South African National Biodiversity Institute), sadly I have to terminate the contract with BotSoc. As a digitizer I’m transcribing the specimen data on Brahms (Botanical Research and Herbarium Management System) database and imaging the specimens. Now I can say loud and clear that the journey to make my mark in the biodiversity sector continues…


What did the men die for?

posted 27 Feb 2017, 02:17 by Linda Dyani   [ updated 27 Feb 2017, 03:24 ]

In few days time the national and provincial governments as well as other institutions of governments will host events to mark the 100th anniversary of SS Mendi. Few sources managed to carry the memory of the tragic sinking of SS Mendi with over 800 men as much as Samuel Edward Krune Mqhayi’s poem “Ukutshona kukaMendi” does. Mqhayi begins his poem with calmness that conceals the shock of death of 607 Black South African men who sailed to Europe to assist Allied Forces in their struggle against Central Powers;

Ewe, le nto kakade yinto yaloo nto.
Thina, nto zaziyo, asothukanga nto;
Sibona kamhlope, sithi bekumelwe,
Sitheth'engqondweni, sithi kufanelwe;
Xa bekungenjalo bekungayi kulunga.
Ngoko ke, Sotase! Kwaqal'ukulunga!
Le nqanaw', umendi, namhla yendisile,
Nal'igazi lethu lisikhonzisile
!

Loosely translated; After all what happened is what was supposed to happen. We, who can anticipate aren’t surprised at all. Your sacrifice is for the good. Our blood is a good offering.

Exactly why did Africans fight along side the British during “The Great War”, 1914-1918? This question is necessiated by the fact that just less than a century ago Africans were engaged in bitter wars to defend their land against the very British that they were supporting during the war. Additionally, barely a year before the British colonial government promulgated an act that made Africans “pariahs” in the lands of their birth, the Land Act of 1913. The conflicts, the brutal murders of  King Hintsa and Chief Bambatha, the incarceration of King Cetywayo, the concentration camps of South African War and many atrocities that British forces visited upon Africans were still felt when the war broke out. Yet Africans volunteered to defend the tyrannical ruler against its enemies.

Perhaps Steve Biko has an answer to this question. Writing about the condition of Black bodies during the second half of the 20th century he observed  “the black man is a shadow of a man; a man completley defeated, drowning in his own misery, a slave, an ox bearing the yoke of oppression with sheepish timidity”.

Africans were completely defeated by the British during the wars that took place in the 19th century. Colonial subjugation determined that they were slaves of the British. Like the enslaved people who were always often ready to defend their masters against any threats Black South African were slaves of the British “bearing the yoke of oppression with sheepish timidity”.  Considering the fact that other subjects of the British Empire, the Dutch who had their own girievance against the empire decided to rebel, adds some weight to Biko’s observation that the black men is “a slave”. Bodies hollowed out by the very tyranny that they went to defend. The white mens’ “artifacts”.

But the were incentives too;

·         Chaplains and Senior Interpreters earned 6 pounds pe month

·         Clerk Interpreters and Sergeants earned 5 pounds a month

·         Hospital orderlies 4 pounds a month

·         Corporals 4 pounds a month

·         Lance corporals 3 pounds a month

·         Labourers (privates) 3 pounds a month.

In cases where Blacks got injured or died whether from diseases or killed, compensation was as follows;

·         Permanent partial disablement 1- 20 pounds

·         Total disablement 30- 50 pounds

·         Death (to dependants) 30- 50 pounds.

And so, over 50 000 Blacks enlisted “not for fighting purposes, but for that class employment that was exclusively or ordinarily suited to Natives, such as drivers, leaders (of oxen) and general labourers in the supply of and other units of the Defence Force”.  

Men who died from Mendi tragedy were the last batch of the South African Native Labour Contingent. They enlisted because they felt that it was their duty to defend their colonial master. Additionally, the promised incentives were too attractive to miss.

When Prime Minister Bothat addressed Parliament on 9 March 1917 to pay tribute to the fallen, he explained, “the toll, I am sorry to say, is a heavy one. ...three Euorpean officers, six European non-commissioned officers and 607 natives, who until yesterday were unaccounted for, must be presumed to have been drowned.

A plague in St Phillips Anglican Church, Grahamstown confirms that 3 of those 607 men came from Grahamstown.

Lindinxiwa Mahlasela is a researcher at Albany Museum.  


Unique view from Observatory Museum

posted 25 Feb 2015, 23:47 by Linda Dyani


If you only have time to visit one museum on your visit to Grahamstown then the Observatory Museum is the place for you.
The Observatory is a unique museum which celebrates the beginning of the diamond industry in South Africa.
The museum, which is part of the Albany Museum Complex opens its doors to the public for an exciting view of Grahamstown.
The tour allows you to get a 360 degree view of the town from the only Victorian Camera Obscura in the Southern Hemisphere, which is housed at the museum.
The Camera Obscura is unique amongst camera obscuras in the world as it has eleven lenses.
The recently appointed manager of the museum, Manzi Vabaza says unlike other structures, which were built for astronomical purposes, the camera obscura was built in 1892 purely as an attraction for the flourishing Manx tourist industry.

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