Saturday, 5 April 2014

It’s Worse in the Water

by Rob Cooper

The vast majority of the surface of planet earth is covered by water and considering this it should be no surprise that whilst terrestrial (living on land) creatures can get rather frighteningly large, the denizens of the depths are always one step ahead. In this article I’ll examine ten of the most fearsome, peculiar and benign ocean creatures with the hope of showing just how fantastic the diversity of ocean live has been over time.

1. Dunkleosteus
Back in the Devonian a peculiar group called the Placoderms developed to truly monstrous sizes. Characterised by their armoured bodies and bony plates instead of the teeth the Placoderms reached their most terrifying in the killer whale sized Dunkleosteus. Strangely for such a large predator the 8 metre long Dunkleosteus could suck prey towards its mouth by rapidly opening its jaws (in less than 1/15th of a second). Unhealed bite marks on the head guard of younger Dunkleosteus also lend evidence to a theory of cannibalism.

2. Helicoprion
If you thought Dunkleosteus had strange teeth you may be surprised to learn far stranger tooth morphologies existed in the prehistoric seas. Helicoprion is a fantastic example of this having a ‘toot whorl’ that looked remarkably like a circular saw inspiring many strange artists’ impressions of the creature. The function of the peculiar teeth has yet to be determined but it is thought that the successive rings of teeth are analogous to growth rings in trees and that teeth successively pushed up to replace those that were lost, similar to how its modern day relatives sharks replace their teeth today.

3. Megamouth Shark
To continue from shark like animals to true sharks we next encounter a very rare modern shark colloquially known as the ‘Megamouth shark’. Since its discovery in 1976 only 55 specimens of this elusive shark have been seen or caught. Like its larger relatives, the basking and whale sharks, the Megamouth has an enormous mouth full of very small teeth that are ideal for sieving plankton from the ocean. As it follows the movement of plankton down to over 200 metres in depth it has small photophores (light emitting organs) to attract plankton and small fish to its 1.3 metre wide mouth.

4. Megalodon
It would be an insult not to mention the mightiest of all ocean predators in this article and Megalodon certainly fits that title handsomely. Well respected as the largest and most powerful predator in the history of all life (with one competitor) megalodon is now estimated at lengths of at least 14-18 metres and up to 20 metres and weights of slightly over 100 tonnes. Megalodon has the largest jaws ever discovered in the animal kingdom large enough for a full grown man to walk through without bending down and an estimated bite force of over 180,000 Newtons. This, along with other palaeontological evidence, suggests that Megalodon preyed on large whales until its extinction 1.5 million years ago.

5. Livyatan 'the great whale'
But what animal was big and ferocious enough to rival Megalodon? Strangely enough the answer comes from a contemporary of Megalodon’s the titanic Livyatan. Livyatan was a raptorial sperm whale which lived between 12-13 million years ago in the Eocene period. Akin to megalodon Livyatan remains have been found alongside those of baleen whales, sharks, dolphins, porpoises and many other sea creatures supporting the hypothesis of Livyatan being an apex predator alongside Megalodon. Unlike modern sperm whales Livyatan had the largest teeth of any animal yet discovered (bar the tusks of elephants and walrus) at up to 36cm in length. Livyatan was thought to ambush prey swimming at the surface from beneath much like the modern great white shark.

6. Leedsichthys 'monster fish'
From two rather fear inducing giants to a rather more benevolent one. Meet Leedsichthys, the largest bony fish to have ever lived. Leedsichthys ranged from around 10 to nearly 15 metres in length so probably rivaled the modern whale shark in size although a heavier bone skeleton likely made Leedsichthys considerably heavier. A strange tendency in large oceanic animals is that of eating remarkably small prey and Leedsichthys was no different and likely fed on plankton either by pumping water through its huge mouth or actively swimming to filter small organisms from the water around it.

7. Giant Manta Ray
Benevolent giants still exist today in the form of the majestic manta ray. Gliding through the waters like marine birds these gentle giants can have a wingspan of up to seven metres and weigh over a tonne. Manta’s are also filter feeders and typically herd their tiny prey into tight balls and swim through at speed with their large rectangular mouths open. On occasion Manta’s have been observed somersaulting through particularly tight balls of prey presumably to catch more prey.

8. Predator X
Leaping back 155 years to the late Jurassic period we come to a group of marine reptiles called the Pliosaurs. Pliosaurs were characterised by short necks and immensely powerful large jaws, the largest specimens having estimated bite forces comparably or far greater than Tyrannosaurus rex. Predator X was one of the largest of all Pliosaurs reaching between 12-15 metres long and possibly weighing up to 45 tonnes. Strangely, compared to modern day marine species, Pliosaurs used their four flippers for locomotion and had no tail fins to speak of; two of these fins would be used for normal locomotion whilst the other two would be used to create a burst of speed when ambushing prey.

9. Plesiosuchus
Crocodiles are often said to be living fossils and quite rightly so for modern crocodilians have hardly changed at all for hundreds of millions of years. However back in the Jurassic period, something very strange happened in crocodilian evolution… They began to adapt fully to living in the sea. At around 6.8 metres in length Plesiosuchus was one of the largest marine crocodiles and like its kin had shed the heavy, restricting armour of its forebears in favour of a streamlined body. The skull of Plesiosuchus shows many similarities to modern killer whales implying it regularly predated on large marine reptiles of the time.

10. Shastasaurus 'ocean giant'
On the topic of marine reptiles, it would be immensely uncharitable of me to finish this article without mentioning the largest marine reptile yet discovered. Shastasaurus was a primitive ichthyosaur, a group of marine reptiles that in their later stages would bear many similarities to dolphins yet the primitive forms were quite unique. The prey base and feeding method of Shastasaurus remains a mystery as it seems to have had no teeth and the suggestion that it fed on soft bodied molluscs is generally not supported by ichthyosaur skull morphology, what this strange animal was specialised for we may never know but that hardly makes it a less thrilling creature to imagine.

The oceans simultaneously offer some of the most fearsome and most benevolent creatures that planet earth has ever harboured. From gentle filter feeding giants to titanic ambush predators lurking beyond the reach of light the oceans are a place where life has fully explored the limits of size. No dinosaur has even come close to the largest baleen whales of today and whilst we may be thankful that many of their huge predators such have Megalodon have finally passed on; we do ourselves a great service by remembering just how rich the oceans are and how important they are as an ecosystem to us and other terrestrial species.

Monday, 24 March 2014

Inside story: Dr Craig Butts - School of Chemistry

Interview by Melissa Levy

Dr Craig Butts is a reader for the school of Chemistry as well as a researcher in the area of structural and mechanistic chemistry, with special emphasis on Nuclear Magnetic Resonance. If you want any more information about what he and his group do then follow this link.

Q. Where did you go to university and what did you study?
“So I studied science at the University of Canterbury in New Zealand, I did a BSC honours in science and then majored in chemistry.”

Q. How did you get all the way from there in New Zealand to here at Bristol?
“I went into science in university basically because I had fun doing it at school! But up until I was about 16 I wanted to be an accountant (this was in the 1980’s and I wanted to be a yuppie (!)) [But] I suddenly realised that accountancy wasn't something I enjoyed a great deal and in fact I much preferred blowing things up in class. And so I went into science at university and…the bit that I really enjoyed was doing the research project in my final year, which made me want to carry on in academic research or in research at least. Particularly due to the encouragement of my supervisor who, about 6 weeks into my project basically just walked up and said “you obviously enjoy this, you’re good at it…do you want a PhD?”. The deal was if I got a first class honours then I could have a PhD place and so I then carried on to do my PhD with my project supervisor working on photochemical reaction mechanisms trying to work out how these photochemical reactions proceeded. In particular we were interested in nitration reactions using a compound that was only really studied in the 1950s as a rocket fuel adaptive by the Russians, tetranitromethane – it was hideous stuff… and we knew that it did this photochemical reaction but we wanted to know HOW it worked and why it worked, and the only evidence that there was in the literature we were pretty sure was wrong!  Near the end of my PhD realised that I hadn’t quite worked out what I wanted to do afterwards! In New Zealand there are not a lot of opportunities around for PhD trained chemists – which was a bit of an oversight on my part - but it never bothered me until that stage! 

So the first email I ever sent outside of the chemistry department in Canterbury was to Professor Rodger Alder here at Bristol and I basically said ‘What’s the deal? Are there any jobs over there? Can I get one?’ and he wrote back and said ‘yeah I’ve got some funding for a post-doctoral research post for 3 years’ and so I applied for that and got it…. I submitted the final draft of my PhD thesis on the morning and on the afternoon I got on a plane to Britain and started my postdoc!”

Q. How did you find his email address or him at all?
“How did I find his email address? I have no idea!! At that stage the web was really early on… I guess there must have been a Bristol website that I would have looked at but I knew to contact HIM because my PhD supervisor had sent students over to him in the past. Once I got over here my plan was always: come over to Britain for 3 years, get this postdoctoral experience which you had to have in order to go and become an academic there… and I never got around to leaving!  I was [now] 23 and I’d never had a job interview, so I applied for a temporary job at the university of Exeter as a lecturer thinking I’d never get it because I’m only 23 and I’ve no experience but I should at least have this practice! And blow me down if they didn’t offer me, not the job that was advertised… they actually gave the job to someone who was already at Exeter and I got his job. So yeah I got lucky basically! [When] I had just submitted the job application I went to the out to celebrate because I was just starting to think that I might actually stay in Britain. I went out to the pub on a Friday night and I started asking everyone in the pub (boys girls whatever) if they had a passport and if they would therefore marry me! And one of the people who walked into the pub subsequently married me! About 5 years later I mean she didn't agree to go out with me for another year! [So] I met my wife and got married and had kids and never quite got around to leaving. Simple as that! 

And then 2005 they closed the chemistry department at Exeter and at that stage I was contacted by my soon-to-be boss here and they said that they had a job here managing the NMR facility, so I took that. It wasn't actually an academic post and so I spent a couple of years getting back into an academic post here at the university and I've been going here ever since.”

Q. If you had to describe the research you do to someone who isn't an expert in chemistry how would you describe it?
“So what we do is primarily to work out the structure of chemicals and we use NMR spectroscopy to do this. NMR spectroscopy is basically the same thing as you do in MRI in hospitals, instead of doing it on a whole person we do it on a very small sample and we look at it on a molecule by molecule basis. My particular research interests are working out ways to better determine those structures and work out what shape they are and what size they are and how they are moving in solution and things like that.”

Q. And how would you describe your typical day?
“Ahh my days are very very varied!  So I split my time into three parts. One is running the NMR laboratory; so I manage the NMR laboratory and I have to, along with the technical staff, look after something like £3 million worth of NMR instruments (soon to be 4 million) and so I spend about a third of my day working with PhD students and post doc researchers who are using those instruments and have run into challenges and problems that they can’t solve without a bit of help, and trying to work out ways to get new instruments which have better or more capabilities. I spend about a third of my time doing research with my own group; so every morning 9 o’clock one of my group come in for their weekly meeting and we talk about how their research is going and what that’s doing. Then about a third of my time or so is spent doing all of the other things that come with academia so primarily teaching, both undergraduate where I teach to the chemistry students but also postgrad teaching which is aimed particularly at NMR spec and the more advanced applications of that to the huge variety of projects that we have in the university.  And then there’s the boring admin bits that we have to do as part of the job.”

Q. Do you have a favourite part of your job? If you had the choice would you chose JUST lecturing or JUST research?
“No… I’d chose to do all of them! To me research is a jigsaw puzzle, you’ve got a problem to solve and you have to know all the different ways of solving it.. Then you start with the corners you build up the edges and then you stick everything into the middle. That’s fascinating to me I mean I get to do that for a living – that’s great fun.  But it’s hard work, there are bits of it which are mind numbing and monotonous and so teaching is a completely different break from that. You get to stand up and get excited about what you do in front of a bunch of people, trying to get them to understand what you do and and why you do it and how you do it, hopefully to the point that at the end of that they know better than you do…I wouldn’t want to do one thing or the other really, if I did either full time I’d die! The paperwork [though] I could avoid quite merrily! “

Q. What do you do when you’re not at university? 
*laughing* “So there are three things I do when I’m not at university. First and foremost I’ve got three kids who are an absolute joy and I spend most of my time... well I’d like to say playing with them and teaching them and all the other things that parents are supposed to do but I think running around after them better describes it. Second thing, I’m a sports fanatic [and] I follow pretty much anything that involve a ball or a bat, so obviously football and rugby and cricket, and then when my wife can’t hear me on a Sunday night I’m often listening to American baseball and bizarre things like that. And the third thing I do is, sad to admit, research.... My research is a hobby for me, pretty much every day in some way fashion or form if I’m not on holiday I’ll be logging in to some of our spectrometers or checking what’s happening or I spend a lot of time talking to people in the states about different NMR techniques and tricks and tips that we can use. I’ve always looked at my job at being my hobby and so I have to come into the office to do my hobby sometimes and other times I get to do it from home.”

Q.What advice would you give to someone looking towards a career in science? Would you recommend academia?
“Absolutely! You have to have the right mind-set; you have to be the kind of person who likes puzzles and problems and likes long term challenges and targets. Academia is about saying ‘we’ve got this big long term goal, let’s start now to solve all the problems and the challenges on the way’ and that’s quite a hard thing to keep focused on over long periods of time. I've worked on projects that have taken over a decade to come to fruition, when they do come to fruition it’s a fantastic thing. I had a look at jobs in industry when I was younger and I just couldn’t do it! I couldn’t do that short term project focus that dominates in industry and commerce. [Academia] is hard work, particularly early on in academic careers, there are a lot of targets you have to achieve very quickly and at a very high level, and that’s very hard to do when you’re just starting out but it’s thoroughly enjoyable. I never ever (I keep telling people this it’s very sad) don’t want to come to work. I never sit here and think ‘oh it’s only 2 o’clock I’ve got another 3 hours before I get to go home’, never happens… I get ‘Oh it’s 4 o’clock I guess I have to leave!’ Not because I don’t want to leave *laughing* but because I have so many things to do and so many things I want to do.”

Q. If you could do science/research with anyone (dead or alive) who would it be?
“I want to do science with people who love science, who get as much enjoyment out of it as I do. To be honest I’m not interested in doing science with Einstein or Marie Curie (well particularly not Marie Curie…) or anything like that, I want to work with lots of people on lots of things and that’s one of the reasons I enjoy my job. I get to do chemistry with 250 side-kicks... Well I guess they’re not my side-kicks …. So I’m going to avoid the question and say that I want to keep on working with the people I’m working with, I mean I get to choose in my job who I work with what I work on when I work on it and to me is all part of the joy of it!”

Thursday, 20 March 2014

Life Without a Backbone

by Rob Cooper

It is a strange turn of phrase common today that having no backbone implies weakness and lack of stoicism. Whilst many of our most impressive contemporary animal species do have well developed backbones there are many critically important animals that lack such a feature. In this article I will attempt to illustrate and expose the diversity and nature of several extinct and extant species lacking said backbone and try to show why they should certainly glean more attention than they have until now.

1. The Colossal Squid 
A wonderfully accurately named animal, the colossal squid is the largest known invertebrate that has ever lived stretching to 14 meters and weighing up to half a tonne. Like all squid the colossal squid is equipped with arms and tentacles covered in suckers, but in contrast to the slightly smaller giant squid, this giant also has sharp hooks for catching large fish and bioluminescent squid species up to 1km below the waves. Once they are fully grown they are only predated regularly by sleeper sharks and sperm whales and still manage to give both predators nasty wounds with their hooks and suckers.

2. The Japanese Spider Crab
The largest member of the arthropod phylum (which includes: insects, arachnids and crustaceans) the Japanese spider crab can have a leg span of up to 3.8 metres and despite it’s rather fearsome appearance it is reported to have a rather gentle disposition. The crab acts as an omnivorous scavenger on the sea floor and like many crustaceans has very small planktonic larvae with transparent bodies and no arms or legs that floats in the water column.

3. The Japanese hornet
Sticking with the Japanese theme we move to a rather less benevolent creature; the Japanese hornet. The sting of the hornet reportedly induces the feeling of your flesh melting and releases a pheromone cocktail that attracts all the hornets in the local area. This pheromone is also used by hornets hunting bees. European bees, which have no defence against the hornets, are often slaughtered by the hive. Japanese bees however have learned to surround the hornet with their bodies and essentially cook the animal with their body heat. 

4. The bullet Ant
If the Japanese hornet wasn’t quite enough to freak you out I invite you to check out the infamous bullet ant. Why is it called the bullet ant? Well the sting of the bullet ant is, according to the schmitd sting pain index, the most painful of all stings and feels akin to being shot. Or if you prefer a slightly more vivid description… The sting is described as ‘waves of burning, throbbing, all-consuming pain that continues unabated for up to 24 hours’. This potent sting is thought to have evolved as a defence against predators that unearth the ant.

5. Anomalocaris
Delving back over 500 million years into the deep past a rather remarkable arthropod called Anomalocaris or ‘abnormal shrimp’ led the way in the evolution of large multicellular predators that would change the evolution of all future life. Anomalocaris was a truly gigantic animal in its time reaching two metres in length and probably preying on soft bodied organisms. The eyes of Anomalocaris like other ancient and modern arthropods were compound eyes and consisted of 16,000 lenses which represents some of the earliest evolved complex eyes able to tell friend from foe and discern environmental factors, which is clearly an incredibly important evolutionary step.

6. Arthropleura
The past often presents us with monolithic, giant versions of creatures we know today. Such is the case with Arthropleura, an ancient relative of millipedes and centipedes that stretched up to 2.6 metres in length and lived in the carboniferous period over 300 million years ago. The carboniferous period was characterised by huge amounts of vegetation and photosynthesis leading to a very high partial pressure of oxygen allowing arthropods such as Arthropleura to grow so large and is also responsible for many of earths current coal deposits hence the nomenclature of the period.

7. The Crown of Thorns 
Skipping forwards 300 million years in time, large invertebrates are still vitally important ecological factors. There is no better example than the mesmerizing crown of thorns star fish, so named for the hundreds of poisonous spines that covers its aboral (opposite to the oral, mouth containing, surface) surface. The crown of thorns feeds on coral polyps and can cause great damage to reefs if they gather en masse. However ecology is rarely so black and white. The crown of thorns provides a vital role in maintaining reef biodiversity by feeding on rapidly growing corals allowing slower growing corals to grow out and allow variance in reef composition. 

8. The Horse Conch
Fearsome snail is a term rarely used. However it is a term that perfectly describes the horse conch. A huge sea snail that lives of the coast of Florida in shallow waters up to 6 metres deep, the horse conch has made a name for itself by feeding on all manner of marine gastropods and arthropods. The horse conch has even been observed cannibalising younger members of the same species. The bright orange flesh of the animal is very striking and is perhaps a reminder of the incredibly diverse forms that even seemingly mundane animals such as snail have and do take.

9. Jaekelopterus
Sea scorpions such as Jaekelopterus were formidable ocean going predators from 460 to 248 million years ago. Jaekelopterus was discovered from a single 46cm long claw by Simon Braddy and Markus Poschmann of Bristol University in 2007. The full animal is estimated at 2.5 metres in length. Whilst not true scorpions, the sea scorpions were some of the largest arthropods that have ever existed and had the common feature of two large claws presumably used to catch prey such as trilobites that shared their primordial seas.

10. The Hagfish

The hagfish is a living fossil; that is a species that has existed relatively unchanged for a very long time period. The hagfish represents a period in evolutionary history just after the vertebrate skull had evolved but before the backbone had become prominent. The hagfish has a cartilaginous skeleton meaning it can literally tie itself in knots, and indeed does in order to provide enough force to tear chucks of flesh of whale carcasses that sink to the deep sea where it lives. The hagfish can produce huge amounts of slime on contact which increases in volume when exposed to water. This slime could be argued to be the most successful predatory fish repellent ever evolved as it clogs the gills of attacking fish preventing them from ‘breathing’. This is evidenced in how almost all known predators of hagfish are birds or mammals.

I hope I’ve demonstrated here that while many of vertebrates we see around us are certainly fascinating and incredibly important, aesthetically, ecologically and commercially, the invertebrates and strange missing links like the hagfish are not only crucially important to the working of our natural world but just as intriguing, beautiful and in some cases even terrifying, despite their disadvantage in size and complexity.