Category Archives: Bio-medical sciences

HPS in 20 Objects Lecture 18: a Cupboard of Dead Bugs

Cupboard of Dead Bugs: Life Lessons from Insects for Economics, Empire and Evolution By Emily Herring

October’s object was well-suited for the month of Halloween. They creep, they crawl, and, in this particular instance, they are very much dead. For the eighteenth lecture in the HPS in 20 Objects public lecture series, PhD students Matt Holmes and Alex Aylward chose to get historical and philosophical about a cupboard of dead bugs. More precisely, a teaching collection belonging to the Museum of HSTM at the University of Leeds. As both speakers demonstrated over the course of the lecture, there is a lot more to be learned from this collection of insect specimen than simply insights into natural history.

Matthew Holmes kicked off the lecture by reminding us of a very important anniversary: 2017 marks the 40th anniversary of the science fiction/horror film Empire of the Ants. The film is very loosely based on a 1905 short story of the same title by H. G. Wells.

1

Both the film and the short story feature humans being tormented by organised attacks from super-intelligent ants. While the film, which was of the unintentionally-funny-0%-on-rotten-tomatoes kind, had one critic saying “you’ll be rooting for the ants”, Wells’ celebrated short story went beyond science fiction and tapped into late nineteenth century and early twentieth century fears about the viability of Western empires. The characters of the fictional world in Wells’ story, feared that the highly intelligent insects might eventually form cultures of their own and seek to start their own colonies. Around the time Wells published his ant story, more practical fears linked to agriculture and health encouraged the development of methods designed to control insect pests, also known as economic entomology. People like Bradford-born entomologist L. C. Miall started listing these different methods of control or extermination which included the not very effective “swatting the insects away by hand” technique and various kinds of noxious sprays which had the unfortunate side effect of killing not only the insects but everything surrounding them. Another method was the introduction of insect predators such as birds. In 1866 British sparrows were exported to New York in an attempt to deal with troublesome caterpillars.

2

The birds did not however limit themselves to the caterpillars and ended up eating the very crops they were meant to be protecting from the insect pests. Therefore, in his section of the lecture, Matt showed that beyond studies in systematics and comparative anatomy, the teaching collections, like the one we have at the University of Leeds, and the development of new forms of practical biology, cannot be separated from the history of the formation of, and attempts to maintain, empires.

In the second half of the lecture, conducted by Alex Aylward, insects, in particular social insects, were also portrayed as pests, but of a different kind. Alex was not referring to the terrible picnic etiquette of wasps but rather to the theoretical puzzles posed by wasps and other hymenoptera that have been pestering evolutionary biologists for decades. For instance, the division of labour between different members of a hive or a colony translates into differences in structure and behaviour. The queen is usually large and spends her life reproducing while some of the workers will usually be much smaller and sterile. Darwin himself worried that these differences in structure and behaviour between the different members of the society might undermine his theory of evolution by natural selection. Indeed, how do the sterile members of an insect society pass on their specific characters and behaviours? In addition, natural selection is often represented as gradually increasing the fitness – i.e. the ability for an entity to survive and to produce other entities similar to itself – of the entities it acts upon. The fitness of a sterile worker in a colony would therefore be zero. In many bee species, sterile castes possess a sting which they deploy in protecting the nest – bringing their own life to an end. Hence, they fail in achieving both aspects of fitness – survival and reproduction. How could natural selection have possibly allowed this situation to evolve?

3

In the 1960s and 1970s attempts to solve these problems involved using the language of economic thinking: costs, benefits, trade-offs, etc. By broadening the notion of fitness to include the reproductive success of others, especially of our close-kin, it might be possible to make sense of the self-sacrificing behaviour of the sterile workers. This was the theory put forth by English evolutionary biologist W. D. Hamilton in the 1960s. If we think of relatedness in terms of shared genetic material rather than simply in terms of parent-offspring, then it becomes apparent that most individuals share as much genetic material with their offspring as with their siblings. In the case of Hymenoptera, the amount of shared genetic material can actually be higher between siblings than between parent and offspring. Certain self-sacrificing behaviours might therefore actually pay off, in terms of extended fitness, by increasing the reproductive output of a close relative, even if the immediate cost is high. Hamilton expressed this in the form of an equation, known as Hamilton’s law, which states the relationship between relatedness, r, the benefit of a behaviour, B, and cost C, in terms of this broader notion of fitness. Hamilton’s work was famously popularised by Richard Dawkins in The Selfish Gene (1976).

Over the course of this lecture, insects went from being portrayed as agricultural pests to theoretical pests. Over the past few decades they can also be seen as having gone from being associated with a threat to humankind which needs to be contained, to a man-made ecological disaster in the making. Efforts to contain insect pests led to the development, in the twentieth century, of synthetic pesticides which have not only contributed to endangering many insect species but have also had a detrimental effect on human health. Recent studies have shown that the alarming rate at which the flying insect biomass is dropping puts us on track for an “ecological Armageddon”. Some of the insects in the Leeds teaching collection can no longer be found in nature. Alex therefore concluded the lecture by drawing attention to calls from environmentally-minded commentators for cooperation on a grand scale in order to tackle the problems flagged up by these recent alarming studies.

 

The video of the lecture is below

Advertisements

HPS in 20 Objects Lecture 11: Astbury Camera or, ‘From Dark Satanic Mills to DNA’

By Alex Aylward

Many of us enjoy rooting for the underdog. The sporting world is probably the arena in which this sentiment is most commonly manifested. But what about the history of science? In the 11th lecture in this series, Dr Kersten Hall and Helen Piel treated us to an underdog’s tale: a tale of Leeds’ important place in the history of molecular biology;  of prescience and priority; of the serendipity of scientific discovery; a tale, as is becoming customary in this series (see lecture 9 on the ‘Anthrax finger’), of wool.

Few scientific achievements are as salient in the public consciousness as the discovery of the double-helical structure of DNA, the genetic material. Most of us know the story of the co-discoverers, James Watson and Francis Crick, announcing to their fellow patrons at the Eagle pub in Cambridge that they had “discovered the secret of life.” And nowadays, as Kersten emphasised, we can barely glance at the news without being greeted by stories of genes-for this-or-that trait, or disease.

Mythbusting is a not-uncommon activity for the historian of science. Textbooks and the media often package up the history of a given scientific episode in neat and convenient ways, jettisoning many of the extra details and actors that make them so fascinating. Nowadays, we rightly remember the essential role that Rosalind Franklin played in the unravelling of the helix. But there are still other strands to the story, missing from the yarn that popular accounts and student biological texts habitually spin. Kersten and Helen ably weaved these additional strands, yielding a more nuanced and inclusive history of the dawn of molecular biology.

 

1

Astbury’s x-ray camera

The textile-inspired metaphors are not accidental. The story centres on wool. When the young William Astbury left London for Leeds in 1928, to take up a Lectureship in Textile Physics, he worried he was “going into the wilderness.” In London he had worked with William Bragg, former Cavendish Professor of Physics at the University of Leeds, who along with his son Lawrence, won the 1915 Nobel Prize in Physics for their work in the development of X-ray crystallography (the principles of which Helen Piel adeptly informed us, with the help of some rather fetching ‘x-ray specs’). Bragg set Astbury the challenge of investigating whether, and how much, X-ray crystallography could tell us about the nature of molecules that make up living things. Wool, being central to Yorkshire’s economy, was an obvious and potentially profitable, place to start. Through this work, crucial steps were made in understanding the molecular structure of proteins, and it represents a milestone in the explication of everyday properties of biological materials (the springiness and stretchiness of wool) with reference to the structure of its constituent molecules.

poem.jpg

A mathematician colleague of Astbury celebrate the latter’s investigation of wool with a poem

In the 1940s, the pioneering work of Oswald Avery (another crucial figure in the origins of molecular biology whose achievements have been perhaps unduly dwarfed in popular histories by those of Watson and Crick) alerted the scientific community to the role of DNA (previously presumed to be a merely structural cell component) as the genetic material. Astbury and his colleagues were galvanised, and against the obstacles of a hesitant University Senate, sub-par infrastructure, and snubs by funding bodies, the X-ray camera was utilised for probing the structure of DNA. Indeed, in 1951, an image strikingly similar to Franklin’s ‘Photo 51’ (which has been described as one of the most important photographs in history, and was a crucial clue in Watson’s and Crick’s proposing the double-helical structure of DNA) was produced. Lacking the conceptual framework for interpreting this image in the way his Cambridge counterparts famously did, Astbury shelved the photo, devoting instead his attention to the manipulation and utilisation of biological fibres towards human ends (resulting in the ICI fashioning him an overcoat made from the fibres extracted from monkey-nuts!). Kersten speculated that, for Astbury, who was guided by an interest in structure, rather than function, a helix (if he had managed to hit upon such a model), might even have been disappointingly monotonous.

bells-image

An image that features in Astbury’s student Florence Bell’s PhD thesis in 1938 showing x-ray diffraction patters caused by DNA

 

The lecture was anything but. The narrative was littered with quips, voice-clips, and anecdotes about locks of Mozart’s hair, as well as profound reflections on what light the story of Astbury’s involvement in the origins of molecular biology could shed on some of the big questions about science and the study of life. Outside of the UK, Kersten mused, mention of Leeds quite often evokes (if it is known at all) mention of The Who’s Live at Leeds, recorded at the University student’s union in February 1970. Kersten and Helen assured us not only that William Astbury should take pride of place in any who’s who of Leeds, but that Leeds itself deserves recognition in any discerning history of molecular biology.

whos-who

Kersten treated us to a real who’s who of Leeds History

The 12th lecture in the series takes place on the 28th February at 6:30pm, in the Rupert Beckett Lecture Theatre. Dr Adrian Wilson and Caz Avery will introduce us to an early stethoscope, throught to have been made by the device’s inventor René Laennec.

HPS in 20 Objects, Lecture 4: The Microscope

In the fourth of the Museum of HSTM’s public lectures, Clare O’Reilly and Juha Saatsi presented a truly integrated historical and philosophical account of the object which has become emblematic of scientific practice – the microscope. Below is an image of the late-nineteenth-century light microscope that was the object of our talk. It is held in the collections of the Museum of HSTM, along with a number of other excellent examples of nineteenth- and twentieth-century microscopy.

20 Objects Microscope

Seeing is believing. But what exactly should we believe on the basis of what is observed through scientific instruments like microscopes? Clare and Juha’s talk highlighted some of the scientific, historical and philosophical problems faced when making realist inferences from microscopic observations.

Clare, a PhD student with @hpsleeds, opened the lecture by introducing our large audience to some of the natural philosophers who documented the unseen microscopic world around them. Robert Hooke and Antony van Leeuwenhoek were two such irrepressibly curious people. Hooke’s 1665 Micrographia was a wonderfully detailed record of his observations, while Leeuwenhoek became known for his ‘little animals’. So extraordinary were their illustrations of magnified fleas, snowflakes and numerous other curios that contemporaries did not know whether to believe they were real.

L0043503 Robert Hooke, Micrographia, flea

‘Engraving of a flea’. Robert Hooke, Micrographia. Wellcome Library, London

The microscope’s reliability remained a subject of debate and uncertainty throughout the eighteenth century. This changed during the nineteenth century, however, as specimens could be cut more thinly and stained with dyes for more ready examination on glass slides. Indeed,the microscope had become such a powerful tool that it allowed biology to become the nineteenth-century science par excellence. A person’s skill now lay in preparing slides and ‘reading’ the images observed on those slides. The level of intuitiveness or inference required to ‘read’ slides meant that microscopy came to be considered an art form, rather than just a scientific procedure. By the 1930s Irene Manton, a plant cytologist at the University of Leeds, was becoming well known for her work with ultraviolet and, later, electron microscopes. Her electron microscope is still held in the collections of the Museum of HSTM.

Drawing upon Clare’s historical introduction, Juha introduced our audience to some of the key philosophical problems surrounding the limits of scientific knowledge and observation. Scientific instruments such as microscopes furnish us with knowledge that transcends what our senses could otherwise perceive of the natural world. But can this ever be an objective experience? What role does inference and observation play in microscopy?

There has been a growing reliance upon technologies that allow us to ‘see’ microscopic phenomena that were previously the subject of inference. The light microscope was one such example. However, it became subject to competing theories of empiricism and realism. Hooke’s optimism about microscopy – that there was nothing too small to escape inquiry, thereby opening up an entirely new visible world – was soon challenged by the empirical theories of his contemporaries. Empiricists believed that scientific instruments did not, as Hooke hypothesised, reveal what existed behind observable phenomena, but instead created entirely new sets of phenomena to be observed and interpreted independently.

Empiricists, such as John Locke, questioned whether phenomena observed under the microscope could be used reliably to understand the natural world. For example, could the ‘nature’ of blood be understood through microscopic examination? Its colour and consistency changed so dramatically under the microscope that Locke believed it impossible to observe its natural mechanisms, which correlated microscope images with what was observable to the naked eye. Locke was not simply highlighting the mechanical limitations of the apparatus. He was philosophically challenging whether microscopes could ever reveal true microstructures, rather than simply an impression open to inference and interpretation.

Today, however, many philosophers have adopted the middle ground between realism and empiricism, and Juha concluded the lecture with a brief discussion of this position. ‘Moderate realism’ posits that we can learn to see with microscopes, but not through them. Microscopes facilitate interaction with the natural world, but do not provide a more high-resolution version of reality. It is instead a continuum of vision.

If you would like to see more commentary and images from this and other lectures in the series, follow the Twitter hashtag #hpsin20.

Wax Models Project

As promised, here is our main event for this term.  Please do volunteer, the idea is that it should work a bit like Hidden Histories in that everyone involved kind of specialises in their chosen object, with the end result being a collection of interrelated stories all being told through different media.

Here anyway, is the flyer designed to entice new and old students to join in.  If you’re interested, please let me know as soon as possible and I can start arranging dates for our experts to come in and talk to us.

WAX MODELS RESEARCH PROJECT

This semester the HPS Museum projectis proud to announce a new project.  In our stores and displays we have some wax heads, wax brains, wax hearts and many
more models made of wax.  We would like to know more about them – why they were made, how they were used, how we can look after them for future generations – in other words, we want to study them in the same way any budding academic, curator or conservator might do.  The aims of the project are:
– To study these objects with an expert historian of wax models and a specialist conservator

– To research one model and tell that story in various ways to various audiences (on our website, our catalogue, on YouTube and so on – this is a highly prized museum skill)

– To send two lucky researchers to Copenhagen to help rescue their wax model collections following devastating floods earlier in the year.

If you are interested in getting involved or just finding out more please contact Dr Emily Winterburn at E.J.Winterburn@leeds.ac.uk

And/or sign up to our blog for regular updates at museumofhstm.wordpress.com