Friday 21 November 2014

FEA for "dummies"

So a lot of my previous posts have talked about finite element analysis or FEA, but I realise some people will not know what the heck I'm talking about unless they've gone and Googled it afterwards. I've ripped huge chunks of the following from my PhD thesis and hopefully made it less academic, as well as interspersing some thoughts throughout.

Finite element analysis (FEA) is a commonly used method in biology and palaeontology (see below) even though it is still quite a recent development (for a historical review see Oden, 1987). Most biological structures are too complex to analyse biomechanically as a whole, so FEA works by breaking these structures (e.g. a skull) into a series of discrete units called finite elements (FE). These can be triangles, cubes, tetrahedra etc. and are interconnected by the corners (nodes). A force replicating a biological load (e.g. a muscle force) can be applied to nodes, and other nodes are constrained (e.g. by a joint) (see figure below). The elements have material properties applied: of particular importance are the Young’s modulus (the elastic modulus - the stress [force per unit area] divided by the strain [the deformation - change in length that occurs under loads]), which determines a materials rigidity and the Poisson’s ratio (the negative of the transverse strain [change in width under load]/axial strain [change in length under load]). With all the complexities of preprocessing done, the whole model is then run in a program that solves a series of complex differential equations for each node, and stress/strain/displacement patterns and orientations can be recovered (Zienkiewicz et al., 2005).




Simplified finite element model. Red arrows are loads, blue triangles are constraints. Each brick (cube) is connected to its neighbours by nodes (black dots).

How do we know it works?
This is one of the most annoying questions you can ever ask someone working on FEA, and likely they will give you some flippant answer. However, I get the chance to explain it with lots of pretty pictures of cool applications. As this method has been used in some form or another for getting on to a century (I don't envy the poor people who had to do the calculations by hand in the time before computers), it's known to be very effective with respect to man-made materials that we know their material properties and structures. Basically what I am saying is Google finite element analysis:


 


Images from: http://www.stressebook.com/finite-element-analysis/ and 
http://www.directindustry.com/prod/msc-software/non-linear-fea-software-finite-element-analysis-6042-493371.html

Instantly the flippant answer becomes apparent. FE modelling is used in all sorts of applications that play vital roles in building everything from planes, to cars and bridges. The design phase of pretty much everything engineering based now goes through a virtual FE phase that is the starting point for in-silico (virtual) testing. When the designs are optimised on computers, the models are made before the final products produced.

That's all well and good, and FEA has worked remarkably well in predicting mechanical performance of engineering structures but there has been some controversy in the predictive/modelling abilities of FEA in the far more complex biological systems that are modelled. Which leads to the next question:

How well does it work on biological material?
The big problem with biological material is often associated with the material properties. Many man-made materials are isotropic (where the properties are the same in every direction) e.g. glass and metals. Indeed many objects are also homogenous with the same material making up the entire structure, thus making modelling easy. However, biological structures are fundamentally difficult. I'm going to focus on bones, as that's what I work on. Most bones are made up of multiple types of "bone" (cortical - that hard stuff on the outside, and cancellous/trabecular - bone that looks like honeycomb on the inside of bones)

Vertebrae, with one sectioned to show internal structure (http://galvacell.wordpress.com/category/uncategorized/)

That's before considering any of the soft tissues (blood vessels, nerves, cartilage, cellular matrix etc.). As bone is mainly hydroxyapatite, it might be assumed it should be easy to model. But biology isn't nice. Under force/loads bones will increase thickness in regions of high stress and strain, and remove bone from low stress and strain. However, osteoblasts (the bone thickening cells) do not lay down the new bone the same way in the entire structure so the structure is not homogeneous, and the material properties for the bone is anisotropic (it bends differently depending on the orientation of the stress/strain). As such there is no quick and easy model for bones, but it is possible to measure the material properties. using using micro- or nanoindentation (Panagiotopoulou et al., 2010; Rayfield, 2011; Soons et al., 2012). These methods basically take a small triangular or diamond-shaped tipped device that "pokes" the bone with a certain force. This leaves an indent of a measurable size (normally micron scale) to give hardness values. The clever ones now actually time the length of time for the bone to "rebound"which is how we calculate the Young's modulus.

The wise amongst you will point out that using micron sized indents to get material properties is probably not an accurate assessment of the whole structure if it is much bigger. Indeed this is an issue, and one way to deal with it is to take many samples across the entire region and take an average. Another option is to model different regions with different properties which might work best for skulls (where there are many bones, so each bone has an average), and to model cortical bone and trabecular bone separately. The problem with doing this is how you divide regions/material properties and it becomes computationally expensive quickly.

But despair not, we can still carry out analyses, but we have to perform validations of our models to check how close models come to real values, either in-vivo (living animals) or ex-vivo (dead material) (Zapata et al., 2010). How this done will vary from study to study, but strain gauges are the most commonly used method for obtaining the in- or ex-vivo strains. However, there are new methods using image correlation or speckle interferometry which work roughly the same as each other - a pattern is created on the bone and the change measured during load application (its roughly the same as INSAR for measure the deformation of Earth before and after earthquakes/volcanic eruptions). This change can be used to calculate strain and patterns of strain. The computer model strains are then taken from the same regions to compare how the digital strains match the experimental ones. So far validation experiments have assessed the fit between FE-model and experimentally derived strains in: birds (beaks: e.g. Soons et al., 2012); mammals (skulls: e.g. Bright and Rayfield, 2011; jaws: e.g. Panagiotopoulou et al., 2010 etc.); and reptiles (skulls: Metzger et al., 2005; jaws: e.g. Porro et al. 2013). With most of the published studies the FE models closely match strain patterns and strain orientations, some struggle to replicate strain magnitudes (especially in complex regions like zygomatic arches): most recent studies match strain magnitudes much closer than older studies.

Porro et al. 2013.


FEA in palaeontology
Whilst now fairly common in palaeontology, it was not until the landmark paper on the cranial function of Allosaurus (Rayfield et al., 2001) that finite element modelling was used on vertebrate palaeontological material. Ever since, it has been used to study broader patterns of theropod cranial evolution (Rayfield, 2005; Rayfield, 2011a), as well as specimen specific questions for feeding in both 2D (e.g. Rayfield, 2004) and 3D (e.g. Degrange et al., 2010). In addition, tests of convergence of rostra (e.g. Rayfield et al., 2007), effects of sutures (e.g. Rayfield, 2004), and deductive methods where heavily simplified models were loaded biologically and destressed regions removed to obtain a structure representing that being studied (e.g. a Diploducus skull: Witzel and Preuschoft, 2005) (finite element structure synthesis or FESS) have also been used. In addition there have been studies on the postcrania: limbs or parts thereof (e.g. Snively and Russell, 2002; Manning et al., 2009), tail clubs of ankylosaurids (Arbour and Snively, 2009), trackways (e.g. Falkingham et al., 2009) and teeth (e.g. Macho et al., 2005)

Rayfield et al. 2001

Again many of you will question what we can garner from fossil stuff as it is not possible to directly test the material properties of extinct animals bone and other tissues, so direct validations are not possible. This poses an issue, but phylogenetic bracketing - where you find the closest living relatives (e.g. crocodiles and birds for dinosaurs) offers an option as it is reasonable to assume that the material properties should fall close to or between the living relatives. Failing that bones can be studied under the microscope and similar structures might be expected to have similar material properties (e.g. cow bone is similar to Allosaurus bone when sectioned - Rayfield et al., 2001).

The result of all of this is that we can often gain insights into stress and strain distributions within fossil taxa fairly reliably. The magnitudes of stress/strain may be off based on material property estimations, but this does not affect our ability to study the patterns within taxa or between taxa or to gain an insight into the function of the fossils. The one major caveat is to do with the effects of soft tissues (mainly because they don't preserve in most fossils), so structures like claws and beaks which are covered with a keratin sheath will inevitably be tough to model, although again estimates can be made if reconstructions are carried out using phylogenetic bracketing.

My dealings with FEA
So where do I fit into this exciting pretty pictured world of stress (and strain)? My PhD relied heavily on the method, so I have been working on a range of studies. I spent the vast majority of the first year trying to validate an ostrich skull (bird skulls have received very little research into them despite being the most closely related to dinosaurs). With much help from Jen Bright during the experimental setup we managed to obtain data from strain gauges on the ostrich skull that was being loaded by an artificial tendon (it was all very cool involving carbon fibre and resin). Strangely, no matter how many materials were included in the digital model (cortical and trabeculllar bone, sutures, beak), we just could not get the data to match up between the two. Despite being an interesting result, the reviewers gave some interesting advice but pointed out that it wasn't validated and thus really wasn't worth of publication at its current stage. So that project has died for the minute but I am hoping that a grant application from Bristol may one day be successful in getting a student/postdoc to pick up the ashes of that work, and make it rise like the phoenix and solve all the birdy mysteries about why their skulls are weird and don't match FE models (or at least why mine didn't - hopefully it isn't because I messed up). It may have insights into modelling dinosaur skulls and be of vital importance.

Screwy ostrich skull. Cuff, 2014 thesis.

After that, I spent spent a chunk of my 2nd and 3rd years carrying out FE studies on ornithomimosaur skulls (will probably end up doing a post about this crazy group shortly). There appear to be differences between some of the taxa depending on feeding methods (pecking or biting), and interestingly there is a cool strain pattern change within the ornithomimsaurs where strains shift from the braincase to the snout. This pattern is also seen in theropods (the meat eating clade of dinosaurs with T. rex and Velociraptor) in general. But, I remain sufficiently vague here because it is still very much work in progress/work in prep for publication so would hate to scoop myself on a blog when publications are all a postdoc really worries about for their career.

I have also had the privilege of working with several students in Bristol during my time there. I supervised a project on a crazy phytosaur (crocodile looking reptiles that aren't closely related at all) which remains a work in progress but hopefully the results of that are published soon. The stand-out project for me (probably because it was my first project of my own) is the one that I initiated at an outreach event (will do a blog on outreach at some point too), and it spiralled into a full on MSc project when Emily Rayfield told me I wasn't allowed to do it in my own time with my PhD being ongoing. That one is on a massive pliosaur (marine reptile from the Jurassic - at least this one was), that was found in Weymouth Bay, UK. Its on display in Dorchester at the museum with a cool display if anyone is keen to see it. Davide Foffa was the MSc student, and reconstructed the skull and muscles and carried out some FE studies on the snout and lower jaw (Foffa et al. 2014) showing that the skull was a relatively weak shape (probably limited by its need for streamlining in the water), but by being massive it compensated for any weakness.

Foffa et al. 2014.


Since then there has been a new MSc at Bristol who has carried out some FE studies on a a crurotarsan archosaur (crocodilian-like reptiles) that looks like the ornithomimosaurs I mentioned earlier. Andrew Jones is now doing a PhD but will hopefully be publishing on this screwy convergence soon with me as a co-author.

I am not personally done with FE just yet for my own. I have some bone validations of my own to carry out on modern cat bones (probably a domestic cat and a lion or tiger) to see how they behave under loading and how accurately we can model them, and that will start soon (maybe early 2015) to continue my yearly battles with this technique. Hopefully that explains what FE is, and what (palaeo)biologists have been up to with it, but feel free to leave comments/questions about any of it.

References
Arbour VM, Snively E, 2009. Finite element analyses of ankylosaurid dinosaur tail club impacts. The Anatomical Record 292, 1412-1426.

Bright JA, Rayfield EJ, 2011. Sensitivity and ex-vivo validation of finite element models of the domestic pig cranium. Journal of Anatomy 219, 456-471.

Cuff AR, 2014. Functional mechanics of ornithomimosaurs. PhD Thesis, University of Bristol

Degrange FJ Tambussi CP, Moreno K, et al., 2010. Mechanical analysis of feeding behaviour in the extinct “terror bird” Andalgalornis steulleti (Gruiformes: Phorusrhacidae). PLoS ONE 5(8): e11856.

Falkingham PL, Margetts L, Smith IM, et al., 2009. Reinterpretation of palmate and semi-palmate (webbed) fossil tracks; insights from finite element modelling. Palaeogeography, Palaeoclimatology, Palaeoecology 271, 69-76.

Foffa D, Cuff AR, Sassoon J, et al., 2014. Functional anatomy and feeding biomechanics of a giant Upper Jurassic pliosaur (Reptilia: Sauropterygia) from Weymouth Bay, Dorset, UK. Journal of Anatomy 225, 209-219.

Macho GA, Shimizu D, Jiang Y, et al., 2005. Australopithecus anamensis: a finite element approach to studying the functional adaptations of extinct hominins. The Anatomical Record 283, 310-318.

Manning PL, Margetts L, Johnson MR, et al., 2009. Biomechanics of Dromaeosaurid Dinosaur Claws: Application of X-Ray Microtomography, Nanoindentation, and Finite Element Analysis. The Anatomical Record 292, 1397-1405.

Metzger KA, Daniel WJT, Ross CF, 2005. Comparison of beam theory and finite-element analysis with in vivo bone strain data from the alligator cranium. The Anatomical Record 283A, 331-348.

Oden JT, 1987. Historical comments on finite elements, in: Proceedings of the ACM Conference on History of Scientific and Numeric Computation. Princeton, New Jersey, USA, pp. 125-130.

Panagiotopoulou O, Curtis N, O’Higgins P, et al., 2010. Modelling subcortical bone in finite element analyses: a validation and sensitivity study in the macaque mandible. Journal of Biomechanics 43, 1603-1611.

Porro LB, Metzger KA, Iriarte-Diaz J, et al., 2013. In vivo bone strain and finite element modeling of the mandible of Alligator mississippiensis. Journal of Anatomy 223, 195-227.

Rayfield EJ, 2004. Cranial mechanics and feeding in Tyrannosaurus rex. Proceedings of the Royal Society B 271, 1451-1455.

Rayfield EJ, 2011. Strain in the ostrich mandible during simulated pecking and validation of specimen-specific finite element models. Journal of Anatomy 218, 47-58.

Rayfield EJ, Milner AC, Xuan VB, et al., 2007. Functional morphology of spinosaur ‘crocodile-mimic’dinosaurs. Journal of Vertebrate Paleontology 27, 892-901.

Rayfield EJ, Norman DB, Horner CC, et al., 2001. Cranial design and function in a large theropod dinosaur. Nature 409, 1033-1037.

Snively E, Russell AP, 2002. The tyrannosaurid metatarsus: bone strain and inferred ligament function. Senckenbergiana lethaea 82, 35-42.

Soons J, Herrel A, Aerts P, et al., 2012. Determination and validation of the elastic moduli of small and complex biological samples: bone and keratin in bird beaks. Journal of the Royal Society Interface 9, 1381-1388.

Witzel U, Preuschoft H. 2005. Finite-element model construction for the virtual synthesis of the skulls of vertebrates: case study of Diplodocus. The Anatomical Record 283A, 391-401.

Zapata U, Metzger K, Wang Q, et al., 2010. Material properties of mandibular cortical bone in the American alligator, Alligator mississippiensis. Bone 46, 860-867.

Zienkiewicz OC, Taylor RL, Zhu JZ, 2005. The Finite Element Method: Its Basis and Fundamentals (Sixth ed.). Butterworth-Heinemann. ISBN 0 7506 6320 0

Saturday 15 November 2014

Postdoc interview

A bit of background to the interview. I was still a few months from finishing my PhD when the first postdoctorate adverts starting appearing in August/September for the coming academic year. As I had only one published paper, and was struggling with another paper to get it published, I felt there was little change of getting any postdoc. However I took it as a change to polish my CV, and get some practice at writing cover letters, and if lucky have some interview training. With my expectation that I'd fail miserably at getting anywhere with the couple of applications, I'd even lined up a project for the remainder of the year.

So I applied for two postdocs, one at the Royal Tyrell Museum in Canada with a project of my own design and the other at UCL and RVC with Anjali Goswami and John Hutchinson respectively and Stephanie Pierce (RVC, now Harvard). With unsuccessful applicants to the Tyrell (thought now would be a good time to tell people its pronounce like squirrel) being warned they wouldn't hear anything leaving me uncertain what the result was, I was delighted to hear back that I would be having an interview with the various members of the team at UCL/RVC.

If you haven't read the other post detailing the project, the project is a Leverhulme funded grant to study the evolution of the postcrania in felids. It breaks down into a PhD bit (being carried out by Marcela Randau at UCL) looking at the morphometrics of the skeleton, and the postdoc looking at the functional mechanics of the vertebrae and limbs. Even with all of the knowledge of the project, and having matched my CV and cover letter as closely as possible, it became vital to make sure I knew as much as I could for the interview. Having never specialised in felids before there was lots of reading and drawing phylogenies to get everything to stick. The postdoc posting wasn't as specific as the PhD advert, so I even read that to figure out more background reading. I did a major refresh on my PhD work, particularly the chapter relating to FE analysis and validation work.

So the 7th October 2013 rolled around for the interview and I felt as ready as I could do on the information side of things. Emily Rayfield (my boss at Bristol) had very kindly offered my the use of her office for the interview (it was a Skype interview) as it was a quiet and private location. I'd brought in my laptop for it, and just before the 1pm interview rolled around I made sure I was changed into a shirt and jacket. I sat at the laptop, connected everything up, and then panicked that I hadn't checked that the microphone was working. The skype call was made, and I stuck my video setting on to prove I was there (and all dressed for the occasion, even if I was wearing jeans that weren't visible). Typically, and if you hadn't guessed, my microphone refused to work. No matter what I did. So I ended up typing my apologies and apologising for my turning red with embarrassment. I turned of the camera function, and then was thankful that Anjali had some credit on her skype account so suggested using the phone line in the office. After a quick google search for the phone number of the office, the phone rang and the interview proper started.

It started with me giving a run down of my research during my PhD, from the validation of a bird skull using finite element modelling to cranial reconstruction of ornithomimosaur skulls and testing them under loads to compare how the skulls may have performed during feeding, and how these herbivorous theropods fed compared to carnivorous taxa. From there the interview drifted into specifics of the project and how my experience fit into the framework of the project. To be honest, most of the interview passed in a bit of a blur, but I do remember being asked how I'd set up a validation of a leg bone and explaining how I would have done it. Looking back I'm sure I'd answer it differently now, but I take that as a sign of a combination of nerves and some extra experience. After all of the discussion on how I would do things, I was asked a bit about if I reckoned I could learn all the new programs etc. Finally they asked about moving to London and if that would have been a problem. Thankfully for me, despite not having thought about it before (shows how little I'd actually thought about getting the job), I do have a lot of friends in London who I knew would help ease the move if it was to happen. With various thank yous for the time, the interview ended with them saying they'd let me know after all the other interviews.

So that was the interview, but not the whole story. Due to my nerves, my shirt was drenched so I was quickly trying to cool myself down as Emily walked back. Anyone who has met me knows I don't really do major stressing or freaking out (one exception may be large conference talks where I do still get nerves). It caused her and her visitor much amusement to see me post interview looking like I'd just come out of the shower. I could not have been happier that it was a skype interview with no webcam at that point. I thought the whole interview had gone as well as I could have hoped. I was thankful for my preparation work, and for taking a piece of paper and pen to it with my to make notes of questions being asked to refer back to later. Having had mixed success at interviews before (rejections from Cambridge at undergrad and a student advisor job, before a successful one for another student advisor post) I was unsure of my success. Anyway I left work to go get a shower and drink to calm down before getting back to work.

Suffice it to say, I was offered the job the next day. Reading that email was incredible. I was shaking with excitement and called my parents to let them know. They quickly levelled my head and reminded me of various things I needed to check before I said yes. However, within 3 days all my questions were answered, and any fears allayed, and I was to be employed at on the project on the 1st February.

Wednesday 12 November 2014

Postdoctorate research

So having thought it through, my first blog post probably should have been on what I actually do for my living, not on a conference I attended... Oops. As such I will now be doing a quick catch up.

So it all started with the imminent end of my PhD almost a year ago. On the 7th October 2013 I had my interview for a position at University College London (UCL)  and the Royal Veterinary College (RVC). Whilst I thought it went well, I couldn't tell how it went (will discuss interview in another post as I think it would make an entertaining post and be fun to hear other people's experiences). Luckily 3 or 4 days later I had an offer that I couldn't refuse to work with Anjali Goswami and John Hutchinson on the biomechanics of felid postcrania. The Leverhulme grant would provide 2 years 4 months of funding for me to carry out the research. If you are wondering why 4 months, its because the grant was written for Stephanie Pierce, who with all of her experience deservedly would be paid more (and get the work done in 2 years). Thankfully for me, she is a bit of a big deal and now is an assistant professor over in Harvard. No pressure following her then (especially as her PhD supervisor was also mine in Bristol)...

So with a rapid transition from having planned my year with part-time work funding research time in Bristol, I had to get my thesis done and move to London. SVP 2013 marked the end of all research time, and from then on it was a rapid completion of my thesis (handed in on the 12th December - was aiming for Friday 13 but finished early). Quickly February 2014 rolls around, and I was starting all of my inductions within the two universities.

So what have I done for my work so far? The first month were mainly inductions plus finishing thesis corrections post-viva (they were very generous in giving me the time to do it, possibly because there were only a few). Since then there has been a big shift in work. Previous research on scaling patterns show that animals undergoing large increases in body size should have to change their posture and gaits to deal with the increases in muscular stresses and strains within their bones. Yet cats do not appear to follow this (almost) law of biomechanics and only seem to make their bones a bit more robust in larger species.



Femora and skulls from domestic cats compared to lion. This shows a size range of about 40 times body mass, to give an indication of how much different the largest and smallest could be.


So my project breaks down into several areas looking at investigating how cats manage to defy the norm:

1) How do felid muscles scale with their body size? If their muscles are doing something that can compensate for what the rest of the skeleton is doing (or in this case not doing), maybe that can explain the lack of apparent posture change in their limbs and backbones. To get at this there have been many many days of dissections looking at lions, tigers (no bears, oh my), snow leopard, jaguar, ocelot, domestic cat, and blackfooted cat. A(n?) European lynx is supposedly on route to round out the full body range. Each dissection involves removing every muscle in the arm, leg, and vertebral series and then bissecting the muscles to study the muscle architecture. Somehow my back has survived these dissections so far so I take that as a victory no matter what the results. (GRAPHIC IMAGES BELOW).

Jaguar dissection showing all of the forelimbs labelled.


Supraspinatus showing the muscle fibres after bissection

If you survived the gory images, well done.
2) How has body mass changed through the evolution of cats? There are about 39/40 living species which occupy a range of body sizes from 1-2kg in the blackfooted and rusty footed cats and up to 300kg in males of the largest tiger subspecies. However, we know from the fossil record there are many more cat species no longer with us, particularly those belonging to the Machairodontinae (the sabre toothed cats). Some of these species reached up to 400-500kg, with estimates from some papers reaching up to 700kg (the size of the largest male polar bear). Are there any trends, and do the fossil taxa change how we view the living ones as a whole?

3) How do certain bones perfom under loads, and can we accurately model them on computers? Taking a selection of limb bones from a small cat and big cat, and vertebral column, simple loads will be applied and then using finite element modelling compared to computer models to see if stress and strain patterns can be replicated.

4) How does the entire post-cranial skeleton perform under physiological loads? Using more complicated 3D modelling (SIMM), and using data from the muscle dissections and videos to validate the movement, can we replicate realistic movements, and how does this affect stress/strain loads on the muscles, tendons and bones under these conditions.

That's just the stuff for my specific work, however I will (hopefully) be publishing PhD things and work from my MSc student from last year (who carried out the project I had planned for my work year). My birthday present from John Hutchinson (one of the PIs) was to be involved in the BBC filming the Horizon series on the Secret Life of Cats. In addition I have a BSc student in the RVC who will be collecting and analysing data from filming of various felid species walking and running. There is also talk of keeping my fingers involved in dinosaur things with some neurocranial anatomy of a sauropod, but we shall see what comes of that.

Other members of "Team Cat" have posts about the project and work to date I have been involved in. Feel free to check out:
http://www.goswamilab.com/#!walking-the-cat-back/c1a4
http://whatsinjohnsfreezer.com/tag/cool-cats/
http://new.rvc.ac.uk/research/research-centres-and-facilities/structure-and-motion/projects/bbc-horizon-cats

Tuesday 11 November 2014

Return of SVP (2014)

So last week marked the return of my favourite conference, hosted this year in Berlin (albeit a little outside of the centre in the Estrel Hotel). The Society of Vertebrate Palaeontology holds its annual meeting on a rotating basis in cities around the world allowing the members to present the results of their research. As the name suggests the topics cover vertebrate palaeontology and this year was no different with everything from fish, dinosaurs, mammals, macroevolutionary trends, taphonomy and even preparation of fossils covered.

My first SVP was in Las Vegas in 2011, and I have been hooked ever since. Ironically a lot of people didn't like the conference in Vegas as it was held in the Paris hotel in all of its twilight glory (as are all Vegas hotels to keep people in perpetual time naivety and thus constantly gambling). Also based on many of the stories of what palaeontologists get up to at conferences, Vegas may have just been a city that overhyped itself and was no crazier than any of the others and somehow disappointed the rest. For the city of sin, it actually was fairly tame for me. I had just started my 2nd year of my PhD and was presenting work from the first year of work. Whilst not ground-breaking I was proud to present a poster on a finite element validation (an engineering technique for studying how structures function) on an ostrich skull. At the time it was the first ones carried out on a bird skull, and I subsequently presented a talk on it at SICB (Society for Integrative and Comparative Biology) in San Francisco early in 2012. As with much science that project went through much work and effort, but unfortunately got stuck and with comments from the conferences and eventually peer-review (to be discussed at another point) has died in its current format (and hopefully a postdoc grant for next year will take the initial results and improve on the methods to turn it into the great project/paper it deserves to be).

I digress from the topic of the post, so back to SVP. Having attended the University of Bristol (which has one of the largest palaeontology departments in the world) for 7 years (MSci and PhD), there are always many people I know at the conference so its a fun place to catch up with old friends and colleagues. Not to mention brushing elbows with all of the higher ups from around the world including some I've been lucky enough to be taught by, and even a few I've been digging in the field with. This year was a bit different however as I was competing for the Romer Prize, an award to the top student talk from the society. Each year the 16 best abstracts from current students, and those within a year after finishing their PhD (how I qualified) are selected and they compete. I can safely say I have never spent longer preparing for a talk (first draft was shown 4 weeks before the conference), and I hope the results showed. I was complimented on the talk by several people and my PhD supervisor said it was the best talk she'd seen me give.



Despite this it was not enough to win, and sadly a Bristol colleague, an ex-Bristol PhD, and 2 other students based in Europe failed to overturn the status quo of US universities winning the prize (although a British student in the US did win, so half moral victory). It must be said I really enjoyed the Romer talk session as all of the talks are of high quality and obviously very polished, a sign of how seriously everyone takes it.

The conference presented much opportunity to peruse posters and listen to a range of talks in everything from dinosaurs (my old passion and topic of my talk), to research applicable to my new job (studying the evolution of biomechanics in felid postcrania). However, it wasn't just all work. One thing you may have guessed from earlier comments was that palaeontologists are a social bunch who enjoy a drink or two (ish). There were many drinks had, over which many of the best academic ideas have been derived (and probably more that weren't so good). Indeed there are the usual mix of food and drinks at the first social/mixer held at the German Natural History Museum (Museum für Naturkunde) with all its cool sauropods and also the famous Archaeopteryx.

(Shamefully stolen from Wikipedia as I don't have a photo)

Then there was the auction which always provides an interesting way for the society to make money to fund various projects and scholarships with the auctioneers this year dressed as 1920s Americans flappers/mobsters (I think). A funny story happened back in 2012 when the conference was in Raleigh where a friend from the US airforce joined me for the auction night and I was explaining the conference. He asked if the conference was a bit like Comicon for us, to which I rapidly denied we were that sort of nerdy, only to walk into the auction and all of the auctioneers were dressed as Avengers characters... Suffice it to say I have yet to hear the end of that one.

The favourite thing for most is normally the big award dinner and afterparty that follows on. This year was no different with a large group of people gathering for the dinner to honour people who have given so much to the science and the society. After the dinner, the formal atmosphere quickly vapourises with the tradition of people swapping name badges (I believe it was originally a way for students to meet high ups and discuss things before attaining their new name/rank), whilst people enjoy drinks, conversations, music and dancing late into the night (indeed if you youtube the 54th annual meeting dancing: http://youtu.be/5sJJ-hfRYIs you can see how even the highest academics can enjoy letting their hair down). With me having to call it an early night to attempt to catch an early flight (which I did manage to do with a fair bit of prompting to wake up after sleeping through alarms), it signalled the end of my SVP for another year. I fear this may be my last one for a while whilst I work on mainly modern material for the remainder of my postdoc, but I'm certain it wont be my last.

SVP I look forward to meeting you again soon!