Tag Archives: zoology

HPS in 20 Objects, Lecture 2: Two-Headed Fish

On the 16th February, the ‘History and Philosophy of Science in 20 Objects’ lecture series held its second event, featuring monsters. PhD student Laura Sellers introduced a large audience to a member of the Museum of HPS’s wet specimen collection: a two-headed shark (spiny dogfish, or Squalus acanthias). The spiny dogfish is an intriguing animal in its own right. Possessing two spines, when attacked the dogfish is able to flex its back to allow one to protrude as a venomous spike. Yet it was the two heads of this specimen (the result of gene overexpression) under examination.


The two-headed fish (right) and a one-eyed piglet (left). The two heads of the fish are the result of gene overexpression. The one eye of the piglet results from gene underexpression.

Emeritus fellow Dr. Jon Hodge began his lecture with an important caveat. Historians of science have long sought to overcome a temptation to tell history as a story of the triumph of modernity over traditional ways of thinking. Yet a tension runs throughout the Western history of monsters, namely between nature as studied by science and nature as interpreted as the art of god by religious traditions.

So how has the emergence of monsters been explained throughout history? Aristotle (384-322BC) viewed all natural objects as a synthesis of form and matter. Form usually imposed itself upon matter, for example turning an acorn into an oak rather than a beech tree. Monsters occurred when matter deviated from form.

Nearly two millennia later, René Descartes (1596-1650) applied his mechanical view of nature – consisting of matter plus laws of motion – to life. Rare movements accounted for the development of monsters. Yet only a generation later, the mechanical view of nature was considered inadequate to explain life: contemporaries instead turned to the divine. A popular idea was the so-called “box-within-a-box” theory; the idea that god had created all forms of life at the first moment of creation, with later forms hidden within the first plants and animals.


The “box within a box” theory was illustrated with a comparison to nesting dolls. Image from http://legomenon.com/russian-matryoshka-nesting-dolls-meaning.html

In the early nineteenth century this theory was confronted by French morphologist Étienne Geoffroy Saint-Hilaire (1772-1844). Geoffrey experimented with animal embryos – shaking, heating or prodding them – and observed the emergence of monstrous characteristics. External influences could apparently change animals from one generation to the next.

Subsequent years saw monsters fall in and out of scientific fashion. Charles Darwin did not discuss monsters as a means of variability (1809-1882). But from the 1880s-1920s biology took a laboratory turn and adopted saltationism. Richard Goldschmidt (1878-1958) devised the theory of “hopeful monsters”: or viable deviations with an evolutionary future. Yet Ernst Mayr (1904-2005), one of the founders of the modern synthesis, thought Goldschmidt harkened back to traditional, discredited views from Plato and Aristotle. Taking a difference stance (1941-2002) was Stephen Jay Gould, who championed Geoffroy. Monsters have lived on into what we think as of modern science.

Simply put, all this reveals that straightforward, traditional to modern narratives don’t hold up. History is complex and scepticism of simple stories is part and parcel of the historians’ trade.

A video of the full lecture can be accessed at https://arts.leeds.ac.uk/museum-of-hstm/20objects/object-2-two-headed-fish/

Matthew Holmes


Natural History Collection Research


Dr Peter Mill and Dr Sandy (R.A.) Baker have both visited the museum recently to conduct research on our collection of parasite wet specimens, c.1950-1980. These samples previously belonged to their former colleague, Dr. R Wynne Owen (d.1985) who was a lecturer in the University of Leeds’ Deparment of Zoology. Wynne Owen’s specialism was fish parasites, but he also collected parasites from other hosts, including invertebrates, amphibia, reptiles, birds and mammals. Peter and Sandy have also been working with Wynne Owen’s collection of microscope slides, which are now housed in the Leeds Museum Discovery Centre

In addition to helping their own research to progress, Dr Mill and Dr Baker’s continuing work on these specimens will provide us with important knowledge about our collection. Their article on will be published in a forthcoming issue of Nature.

Last Friday we were also visited by Clare Brown (Curator of Natural Science at Leeds Museums and Galleries), who kindly offered expert advice regarding the care of our natural history collection.  We’re very pleased to see things progressing so well with this collection, and hope there will be more exciting work in the near future.

Lepidoptera Collection at leeds.

Hello all, firstly thanks to Mike for setting me up so I can start blogging.

Secondly, here’s what I’ve done so far on my chosen object- a lepidoptera collection in the biology collections at leeds. I’ve found it hard to find out specifics about the object, but alot on lepidoptera in general. I’ve got my piece and an atempt at a 30 word label below. Please send feedback so I improve it.

Butterflies and moths both belong to an order called the ‘Lepidoptera’. Which is one of the most diverse groups of insects on the planet, estimates of the number of species range from a 100,000 to a quarter of a million, divided into between 125-175 families depending on who you talk too. Their diversity and notorious beauty from around the world can be clearly seen in the specimens here in Leeds because they have been obtained from many places, such as the Americas (labelled as ‘new world butterflies’ in this collection). The Lepidoptera play an enormous role in pollinating the earth’s planet population and form a vital part of the food chain.

Surprisingly there is no taxonomic difference between a butterfly and a moth, indeed it would taken expert to tell which of the species in these cases where moths and which where butterflies. Despite many generalizations, and several detailed looks by taxonomists there is no distinction that can be drawn upon, it seems some families of butterflies are closer to families of moths than they are to other species of butterfly. One of the most widely held generalizations for example is that moths are nocturnal and butterflies are not. Though this is true for the butterfly, it is not so for moths, many species are Crepuscular (active in twilight, at dawn and dusk), and of the 2,500 species of moth endemic to Britain, a hundred are active during the day, but there are only 60 species of butterfly in Britain, and so there are more species of moth flying around in the day than there are butterflies.

The origins of the names ‘butterfly’ and ‘moth’ are largely lost in time, but there are several theories surrounding them. There are two theories of the word ‘butterfly’ firstly, that it comes from the old English word ‘buterfleoge’ meaning ‘butter-coloured flies’. The second idea is that it comes from the old English ‘flutter-bys’, in parallel with an old English belief that witches took the form of butterflies to steal milk and butter.  This is doubted, even if butterflies and witches did really, really like butter (?)… How much can a butterfly carry? But it is still a nice idea.

The origins of the ‘moth’ are more mundane; there are numerous languages from which it could have originated most interestingly is from the word ‘midge’ a common term in English used up until the 16th century to indicate larvae, usually in reference to the devouring cloth.  This leads to a great misconception of moths; that they eat clothes. Moths love to lay their eggs in dark recesses, making your wardrobe the perfect place to breed. But of the afore mentioned 2,500 species of moth in Britain only 6 of their larvae have been shown to actually eat textiles, giving the rest of them a bad name.

Whatever the origins of their names, they have always been treasured for their beauty, and more recently used in science as a model organism for ecology and genetics as they are so old (studying the change in genes over millions of years). Though this research has happened in Leeds to a limited extent, the collection here was never used for this and was probably more used for teaching in identifying butterfly species.


Moths and Butterflies are known as the ‘Lepidoptera’, their use in science is limited but are treasured for their beauty and diversity, so collections like this one are common.