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Sweet seventy-five and never been kissed. The Natural History Museum's Tendaguru brachiosaur Mike Taylor University of Portsmouth

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Presentation on theme: "Sweet seventy-five and never been kissed. The Natural History Museum's Tendaguru brachiosaur Mike Taylor University of Portsmouth"— Presentation transcript:

1 Sweet seventy-five and never been kissed. The Natural History Museum's Tendaguru brachiosaur Mike Taylor University of Portsmouth

2 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth This is where were headed in the next twenty minutes: Historical background German expeditions British expeditions The M23 sauropod of Migeod and Parrington Material Migeods account Comparison with Brachiosaurus specimens Overview

3 Historical background The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth From , German expeditions led by Werner Janensch excavated dinosaur bones from Tendaguru Hill in what was then German East Africa (now Tanzania). Map modified from Maier 2003

4 Historical background The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth The expeditions used hundreds of native labourers and recovered many spectacular specimens. Photo modified from Maier 2003

5 Historical background The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth The best-known result of the German Tendaguru expeditions is the Brachiosaurus brancai mount at the Humboldt Museum in Berlin. This includes elements of the holotype HMN SII (although the mounted skull and vertebrae are plaster models).

6 Historical background The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth That's Diplodocus down there, looking like a toy.

7 Historical background The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth German East Africa changed hands in the Great War ( ), becoming the British territory of Tanganyika. The British Museum (Natural History), aware of the German material, wanted to recover its own exhibit-quality specimens. From , the BMNH sent a series of expeditions led first by Cutler and Leakey, and then by Migeod and Parrington. They went with the express intention of recovering a specimen for display. This talk is about what they found.

8 The M23 sauropod The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth In the 1930 field season, Migeod and Parrington opened their 23 rd quarry, named M23. This proved to contain the greater part of a sauropod skeleton, which was excavated and shipped to London. It is widely assumed to be Brachiosaurus brancai. This specimen has often been incorrectly referred to as BMNH M23 (e.g. Paul 1988), but is correctly BMNH R 5937.

9 The M23 sauropod The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth In the 1930 field season, Migeod and Parrington opened their 23 rd quarry, named M23. This proved to contain the greater part of a sauropod skeleton, which was excavated and shipped to London. It is widely assumed to be Brachiosaurus brancai. This specimen has often been incorrectly referred to as BMNH M23 (e.g. Paul 1988), but is correctly BMNH R I call it The Archbishop.

10 Material The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth The material identified and excavated by Migeod includes: Three teeth (doubtfully associated) A sequence of at least 21 articulated presacral vertebrae (probably C4-D11, with maybe D12 and even D13) Sacrum, consisting of five vertebrae A sequence of nine articulated caudal vertebrae Cervical ribs and ossified tendons (probably the same) Dorsal ribs Left scapulocoracoid Both humeri Ilium, broken ischium and partial pubis Broken femur, fragments of another, and a calcaneum

11 Material The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth The material identified and excavated by Migeod includes: Three teeth (doubtfully associated) A sequence of at least 21 articulated presacral vertebrae (probably C4-D11, with maybe D12 and even D13) Sacrum, consisting of five vertebrae A sequence of nine articulated caudal vertebrae Cervical ribs and ossified tendons (probably the same) Dorsal ribs Left scapulocoracoid Both humeri Ilium, broken ischium and partial pubis Broken femur, fragments of another, and a calcaneum Awesome!

12 Material The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth This actually compares pretty well with HMN SII Skeletal reconstruction modified from Wedel Pink bones were excavated in 1930.

13 Prepared material The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Skeletal reconstruction modified from Wedel Pink bones were excavated in Red bones have been prepared.

14 Migeod's 1931 account The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth The only published paper on BMNH R 5937 is Migeod's (1931) account of the 1930 field season. This says many surprising things, such as: The anterior dorsal vertebrae apparently had their neural spines in two parts, which led me at first to the opinion that this dinosaur was a Dicraeosaurus. This view proved on further excavation to be untenable, and indeed the bifurcate spines were similar to neither species of Dicraeosaurus found at Tendaguru by the Germans

15 But how far can we trust Migeod? The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Parrington soon discovered that Migeod's pretensions concealed a profound ignorance of many subjects. -- Charig's obituary of Parrington. The few good bones he collected would not constitute a single limb and but a few feet of backbone. Indeed, much of East Africa was enclosed in plaster with the mistaken impression that bone was contained within. -- W. E. Swinton, letter to John McIntosh, October A charlatan -- Parrington's description of Migeod.

16 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth... and my favourite... Migeod does not have the slightest notion of palaeontology. -- Friedrich von Huene, letter to Janensch, March But how far can we trust Migeod?

17 So what can we trust? The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth The quarry map is very useful. While the association of the scapula and humeri are doubtful, it shows that the vertebral sequence is real.

18 Neck/torso proportions The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Vertebra Length (cm) Source C9 99 Migeod C Migeod C11 94 Interpolation C12 84 Migeod C13 61 Migeod D1 36 Migeod D2 28 Migeod D3 27 Migeod D4 27 Interpolation D5 28 Migeod D6 29 Interpolation D7 31 Interpolation D8 32 Pers. obs. D9 34 Pers. obs. D10 29 Interpolation D11 23 Migeod D12 23 Interpolation Total length of proximal neck (C9-C13): 442cm Total length of torso (D1-D12): 347cm Proximal neck/torso = 1.27 In HMN SII, this ratio is 1.11 So the Archbishop's neck is proportionally 14% longer. (probably more, in fact.)

19 So what is the Archbishop? The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth General shape of vertebrae is definitely Brachiosaurus-like. Proportionally longer neck suggests something unusual. Migeod's bifurcated neural spines are intriguing. Migeod also described great wings in D1-D4. Proportions of appendicular skeleton are all wrong, e.g.: Archbishop humerus/C9-C13 = 146/442 = 33% HMN SII humerus/C9-C13 = 213/466 = 48% So Archbishop humerus is only 70% expected length! (IF we can trust Migeod's measurement and association.) This suggests that it might not be Boring Old Brachiosaurus.

20 It's time to look at the material! The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Four cervicals (3 visible) Two good dorsals Two dorsal centra Long-bone fragment

21 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Far too much material for 20 minutes! For the rest of this talk, I am just going to look at dorsals A+B They are very well preserved, especially on the right side. Some parts are reconstructed in plaster, but this is mostly easy to spot. The lateral processes are broken on both sides.

22 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Which dorsals are they? Migeod 1931 says: All the dorsal centra [...] were with one exception adhering very firmly to each other, especially the more anterior ones, so that some of them could only be separated by cutting […] The exception was a break between D6 and D7. So A+B are Migeod's D7 and D8. However, these vertebrae of Migeod's usage are in fact D8 and D9, as an extra dorsal was found beneath his D6 after the numbers were assigned.

23 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Comparison with Brachiosaurus type specimens Posterior dorsals of each specimen. Archbishop (BMNH R 5937) D8 and D9 Brachiosaurus altithorax (FMNH P 25107) D8 Brachiosaurus brancai (HMN SII) D7

24 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Comparison with Brachiosaurus type specimens Posterior dorsals of each specimen. Archbishop (BMNH R 5937) D8 and D9 Brachiosaurus altithorax (FMNH P 25107) D8 Brachiosaurus brancai (HMN SII) D7

25 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Serial variation among B. brancai dorsals D11 and D10D9 (modified from Janensch 1950) D4D7 The preserved dorsal vertebrae of the Brachiosaurus brancai holotype HMN SII are very different. This does not make it is easy to compare the Archbishop dorsals with Brachiosaurus brancai.

26 Dorsals A+B have five characters not seen in classic Brachiosaurus: Tips of neural spines subcircular and anteroposteriorly long. Reduced rugosity on posterior face of spine. Lateral ridges on pedicels. Neural spine tall relative to centrum length. Cotyle taller than wide. The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Anomalous characters

27 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Archbishop (dorsal view, at right) Spine caps are relatively large, and irregularly shaped (subcircular). 1. Tips of neural spines subcircular and large Brachiosaurus altithorax (dorsal view, at right) Brachiosaurus brancai (left posterolateral, below) Spine caps are roughly semicircular with the flat face at the back.

28 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Dorsals A+B, showing total anteroposterior length of both spine-caps (red) and centra (blue). Total spine-cap length is 62% total centrum length. In Brachiosaurus altithorax (left), it is 40% In Brachiosaurus brancai (right), it is 35% 1. Tips of neural spines subcircular and large

29 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 2. Reduced rugosity on posterior face of spine The Archbishop has a T-shaped rugosity composed of semicircle like that of B. brancai together with a broad, shallow, rugose postspinal lamina. Brachiosaurus altithorax has distinctive triangular rugosities on both faces of the neural spine. Brachiosaurus brancai has a semicircular rugosity, with the flat part directed ventrally.

30 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 2. Reduced rugosity on posterior face of spine The Archbishop has a T-shaped rugosity composed of semicircle like that of B. brancai together with a broad, shallow, rugose postspinal lamina. Brachiosaurus altithorax has distinctive triangular rugosities on both faces of the neural spine. Brachiosaurus brancai has a semicircular rugosity, with the flat part directed ventrally.

31 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 3. Longitudinal ridges on pedicels of neural arch Both dorsals have prominent ridges running along the neural arches. In posterior view, the neural arch appears waisted below the ridges. I have not seen this morphology in any other sauropod.

32 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 4. Neural spine tall relative to centrum length D8+9 of Brachiosaurus altithorax (left), B. brancai (middle), and Archbishop (right). Centra scaled to similar lengths. Archbishop verts are 30% taller than B. altithorax, 20% taller than B. brancai.

33 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 5. Cotyle taller than wide Archbishop cotyle (above) height/width = 1.16 No crushing is apparent. Brachiosaurus brancai cotyles (left) Upper: SII:D7 -- height/width = 0.62 Lower: AR1 -- height/width = 0.60

34 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Conclusions BMNH R 5937 includes some very well preserved material (despite Swinton's dismissal of the specimen). The skeleton is comparable to HMN SII in completeness. Much of the excavated material remains unprepared. Migeod's interpretations of the material are unreliable. The specimen is a brachiosaurid sauropod. Serial variation in Brachiosaurus brancai makes it difficult to interpret the NHM specimen. The Archbishop's neck is proportionally longer than in B. brancai. BMNH R 5937 may represent a new taxon, based on five unique characters of the well-preserved pair of dorsals.

35 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Acknowledgements Thanks are due to … Dave Martill for his supervision. Sandra Chapman and Paul Barrett (Natural History Museum), Dave Unwin and Wolf-Dieter Heinrich (Humboldt Musuem fur Naturkunde) and Bill Simpson (Field Museum of Natural History) for access to specimens. Matt Wedel for making me realise I could do this. This work has not been supported by any grant. Please feel free to remedy this deficiency.

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38 What happened to all that material? The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth It's all a bit of a mystery. Unfortunately the [1930] expedition (no fault of Parrington's) was ill-conceived and ill-prepared. They did collect the greater part of the skeleton of a huge brachiosaurid dinosaur; but even that was left for decades to rot in the basements of South Kensington, the only elements that were ever prepared and exhibited being two gigantic vertebrae. -- Charig's obituary of Parrington. For whatever reason, most of the material is still in jackets.

39 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Cervical P

40 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Cervicals S and T

41 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Cervicals S and T That's cervical T in the background

42 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Cervical U

43 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Dorsals A and B

44 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Dorsal centra Q and R

45 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth Long-bone fragment (distal femur?)

46 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 2. Reduced rugosity on ant/post faces of spine Archbishop's posterior rugosity consists of a semicircular region... with a low, broad, rugose postspinal lamina below.

47 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 2. Reduced rugosity on ant/post faces of spine Archbishop's posterior rugosity consists of a semicircular region... with a low, broad, rugose postspinal lamina below.

48 The Natural History Museum's Tendaguru BrachiosaurMike Taylor, University of Portsmouth 4. Absence of hyposphene The Archbishop has NO hyposphene: just a narrow medial infrapostzygapophyseal lamina. BUT is this just a preparation defect? Brachiosaurus brancai, HMN SII, D4. This is a typical brachiosaur hyposphene.


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