The age of mammals nature development paleontology in the long nineteenth century 1st edition chris
the Long Nineteenth Century 1st Edition Chris Manias
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Traveling Irishness in the Long Nineteenth Century 1st Edition Marguérite Corporaal
A history of modern political thought in East Central Europe. Vol. 1, Negotiating modernity in the ’Long Nineteenth Century’ First Published In Paperback. Edition Baár
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ISBN 13: 978-0-8229-4780-6
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Cover art: Painting of a Megatherium by Heinrich Harder from Tiere der Urwelt. Wandsbek-Hamburg: Verl. der Kakao Compagnie Theodor Reichhardt, ca. 1900.
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Chapter 8. Development, Origins, and
Part III. Global Transformation and New Histories of Life, 1890 s –1914
9.
Chapter 10. The
Chapter 11. Ordering the Pampas and Patagonia
Chapter 12. Lands of the Diprotodon
Chapter
Chapter 14.
Part IV. The End of the Age of Mammals
Chapter 15. The Coming of the
ACKNOWLEDGMENTS
I began this project in 2015, and spending a turbulent seven years (marked by the Covid-19 pandemic, continued environmental decline, large-scale industrial action, and a host of other things) at least partly in the company of giant sloths, mammoths, paleotheres, and other fossil mammals has been both a welcome opportunity and a spark to think about the world in a new light. This book would not have been possible without a range of support, help, and comradeship of various kinds, and I am delighted to acknowledge this here.
Over my academic career, Peter Mandler and Jan Rüger have provided tireless support since my PhD, for which I am extremely grateful; Robert Bickers, Kate Fisher, and Mark Jackson all provided crucial support for earlier iterations of the research. Colleagues at the University of Manchester and King’s College London have been essential for helping the project develop, and for providing a stimulating and collegial work atmosphere. In particular, thanks are due to David Edgerton, Caitjan Gainty, Vincent Hiribarren, Anna Maerker, Julie Marie-Strange, Paul Readman, Adam Sutcliffe, and Abigail Woods for ideas, feedback, and conversation. At King’s, the Centre for the History of Science, Technology and Medicine has proved a stimulating and supportive intellectual home, and I would particularly like to thank my colleagues here. My students, especially in the modules Defining Race and Culture, Humans and Nature, and Worlds in Objects, have always given me inspiration, new ideas, and encouragement to see things in new ways, and I am very grateful to them.
I am also extremely thankful to The British Academy (award: R117065), the University of Manchester, Princeton University Library, the American Philosophical Society, the Arts and Humanities Research Council, and King’s College London for funding my research, which has allowed the project to take on such a wide-ranging and international character.
The book would also have been impossible without the support and help of staff in archives, libraries, museums, and other collections. I have
particular gratitude to David Gelsthorpe and Henry McGhie (Manchester Museum); Greg Raml, Susan Bell, and Ruth O’Leary (American Museum of Natural History); Linda Oliveira (Princeton Library); Lisa Sisco (Carnegie Museum); Marie-Astrid Angel (Laboratoire de Paléontologie, Muséum National d’Histoire Naturelle); Franz Xaver Schmidt (Staatliches Museum für Naturkunde Stuttgart); Richard Hulser (Natural History Museum of Los Angeles County); Lea Gardam (South Australian Museum); Vanessa Finney (Australian Museum); Wendy Crawford (Western Australian Museum); and Josh Caster (archives of the University of Nebraska-Lincoln). I am also grateful to the staff at the British Library, Staatsbibliothek zu Berlin, Bibliothèque Centrale du Muséum National d’Histoire Naturelle, Archives Nationales de France, and London Natural History Museum Library and Archive.
My thanks are also due very much to the University of Pittsburgh Press. Abby Collier has steered the project magnificently and has persistently been helpful and encouraging. The anonymous readers of the manuscript also provided great help in sharpening and shaping the work, and giving it more coherence than it might otherwise have had.
One of the most enjoyable parts of this project is how it enabled me to build a community with other people interested in the cultural role of the deep-time sciences. The Popularizing Paleontology: Current and Historical Perspectives network, which grew alongside this book, has provided a great deal of stimulation and insight into the history of paleontology, and a genuinely friendly support group to deal with larger questions. Discussions with Paul Brinkman, Joe Cain, Pratik Charkrabarti, John Conway, Vicky Coules, Kirsty Douglas, Richard Fallon, Oliver Hochadel, Ellinor Michel (and the rest of the Friends of Crystal Palace Dinosaurs), Darren Naish, Bob Nicholls, Ilja Nieuwland, Elsa Panciroli, Irina Podgorny, Lydia Pyne, Sadiah Qureshi, Lukas Rieppel, Efram Sera-Shriar, Marco Tamborini, Will Tattersdill, Mareike Vennen, Mark Witton, and Rebecca Wragg-Sykes have been particularly helpful at various times, and I am especially thankful to those who were able to give comments on draft writing.
Of course the book has also only been possible with wider support. My parents have given me unflagging help throughout (and not least frequent queries of “How is the book going?,” often at times when the book was not necessarily going). The book has also benefited from conversations about animals and history with Alex, Tom, Nick, and Emma. Jana and Andreas
Remy, and Heike Ewert have listened and helped with numerous things at numerous times. And it would be amiss in a book about connections between mammals and humans for me not to thank Belle and Yuri, my principal nonhuman mammalian friends. This book however is mainly for Elinor, who has been the best comrade and companion I could have hoped for in this and other journeys.
THE AGE OF
MAMMALS
INTRODUCTION
Constructing an Age of Mammals
OVER THE NINETEENTH CENTURY VISITORS TO METROPOLITAN MUSEUMS AND READERS of popular science books became familiar with a menagerie of extinct beasts. These included the mammoths, mastodons, dinotheres, and other ancient proboscideans, ancestors and relatives of modern elephants. The giant “toothless” edentates of South America, including the ground sloths and armadillo-like glyptodons, were known since the early nineteenth century. From North America came the horned herbivores like the dinocerata and titanotheres, and carnivores like the short-faced bear and saber-toothed cat. Fossil remains showed Europe had recently been inhabited by cave bears, hyenas, lions, woolly mammoths, aurochs, and hippopotamuses. More creatures were excavated in colonial territories, including great giraffids from India, and fossil marsupials from Australia. Evolutionary displays showed the step-by-step development of familiar creatures, such as horses and camels, from small early forms to the modern animals. The diversity of past life formed a narrative of the Tertiary and Quaternary periods—enshrined as “the Age of Mammals”—moving across the lush jungles of the Eocene, the bountiful forests and plains of the Miocene and Pliocene, the harsh Pleistocene glacial epoch, and the current “Age of Man,” when most of the great beasts were lost.
Building this history for the mammals required diverse knowledge and expertise. Fossils were excavated in places connected to expanding nineteenth-century economies, including mines, quarries, agricultural fields, urban building sites, and territories surveyed for settlement and exploitation. Interpreting the remains required imagination and debate, as scholars compared ancient bones with modern animals and fashioned fragmentary fossils into workable specimens. Prehistoric animals were imagined by scholars, publics, and artists, and elaborated in novels, poems, and popular science works. These genres brought an unknown past to life and constructed a history for the animal world. The ancient history of the mammals could provoke wonder at the spectacles of creation, horror at fearsome beasts and their terrible relations (and their imagined terrible deaths), evocations of transcendent or perplexing mysteries, calls to action for research or preservation, or humorous musings on creatures that seemed strange and comical. The lost beasts of prehistory were discussed in various registers, building their relevance to the present. The mammals showed life and the earth had a history with moral messages. Like human history, this could be conceptualized as a story of confident progress, or of decline and fall and fears for the future. The sedimentary eras of the Age of Mammals undergirded understandings of nature and humanity, where faith in progress was tempered by uncertainty and trepidation.
This book is about how the deep history of the mammals was constructed across the nineteenth century, and its implications for the current world. Its starting point is that—contrary to current interest in dinosaurs—nineteenth-century scholars and public audiences seeking dramatic lessons on the history of life focused inordinately on mammals. Mammals were thought to represent the pinnacle of animal life and were crucial for understanding the natural world. Yet the assumed dominance of mammals combined with troubling notions: promising creatures had been swept aside in the “struggle for life,” and modern nature was “impoverished” compared to previous eras. Why some ancient animals, such as the saber-toothed cat and ground sloth, became extinct, while others seemed to be precursors of familiar creatures like elephants and horses, were problems loaded with cultural assumptions and ambiguity. How humans related to deep developmental processes, and how the Age of Man differed from the Age of Mammals, provoked reflections on humanity’s relationship to the natural world. Ancient mammals became crucial for engaging with nature and the environment, and the past, present and future of the world.
The Age of Mammals was constructed as the last era of earth’s history, setting the foundation for the modern world. But this former world was not conceived as entirely lost. Sedimentary views of time and globalized visions of the natural world meant that remnants of ancient life were thought to still be present in places considered removed from progress. The “denial of coevalness” was a defining technique within nineteenth-century anthropology, colonial rule, and racial and cultural othering, as people and places around the world were defined by Western scholars as relics of past stages of development.1 The modernity of many humans was denied, as was the modernity of many landscapes, animals, and plants. Debates over fossils, and reconstructions of organisms and ancient environments, marked particular creatures and locations as “progressive” or “primitive,” “developing” or “decadent,” “general” or “specialized,” terms with strong ideological resonances. Studies of fossil mammals naturalized ideas of how familiar animals like the horse and the elephant came to be, how the life of South America and Australia was distinct from that of other places, and why Africa seemed to be the one place in the world where some great beasts survived. Fossil mammals linked nature with social, cultural, and economic values. The construction of hierarchy and order in the history of the mammals was inseparable from the construction of hierarchy and order in the modern world.
Paleontology across Boundaries and Borders
The growth of the concept of “deep time” is now regarded as one of the most significant shifts in human understandings of their place in the universe. Indeed, Martin Rudwick argues that the establishment of “the earth’s deep history” should be regarded as one of the great conceptual revolutions, along with the Copernican, Darwinian, and Freudian.2 Partly this was because of the tremendously long chronologies promoted by geology and paleontology, which constructed an earth history far beyond the time spans deduced from the Bible or the chronologies of India, China, and Pharaonic Egypt. Interest also derived from the sense of change and unfamiliarity. The earth and nature were reevaluated through ideas that landscapes had, in former ages, been radically different: covered in jungles filled with giant reptiles, or glaciated landmasses home to mammoths and great bears. How far back did this history go? How could it be made known? What forces drove change in the natural world? Was there a plan or order behind it? And what was the
relationship between fossil organisms and the modern world? Behind these questions were sedimentary ideas of time and development. Geology and paleontology showed successions of environments layered on one another. There was no single timeless past or original state of nature, but a series of eras which stretched through the layers of the earth. Fossils and geological landscapes were gateways into these former worlds.
More recently Pratik Chakrabarti and others associated with a drive for “new earth histories” have examined the conceptual power of deep time obliterating other means of understanding the world and its pasts.3 These studies argue that the establishment of deep time was intrinsically connected with structures of economic and political power. While recognition of connections between political ideology and evolutionary sciences is not new, 4 this more recent literature has taken a material and institutional focus, arguing that the construction of deep history was inseparable from control over territories and extraction of mineral resources. Katrin Yusoff has drawn attention to how “the sleight of hand of the Janus-faced discipline of geology (as extractive economy and deep-time paleontology of life-forms) is to naturalize (and thus neutralize) the theft of extraction through its grammars of extraction.”5 The extraction of fossils, the extraction of mineral resources, and the establishment of systems of authority are not separate stories, but deeply entwined. Similar observations have been made in the history of paleontology. Lukas Rieppel has argued that the paleontology of “the long Gilded Age” in the United States was predicated on the changing capitalist economy, drawing in people and techniques from mining, industry, corporate administration, and philanthropy, often in politicized and socially controlling ways.6 The study of fossils was inscribed with power and linked with empire and economic dominance.
We therefore have a strong literature showing the conceptual importance of deep time, and how it was conditioned by power and control over the natural and human worlds. This book seeks to develop these perspectives, further linking nineteenth-century histories of the earth with the workings of cultural, political, and economic authority. The elaboration of the history of the mammals shows the connections between ideologies of progress and hierarchy, and how the natural world was inscribed with moral values. It also shows the wide ranges of people and places involved in these processes. In some respects it is a story of power and control. Mammal paleontology was connected with expanding nineteenth-century economies and was often
furthered through empires and nationalizing states. Intellectually too the history of the mammals was constructed around ideas that living things could be arranged in scales of worth. However, the elaboration of the Age of Mammals also shows unevenness in both these areas. The geographic framing of the Age of Mammals reinforced the power and hierarchy of established centers, but could also displace them, by making areas regarded as strange, primitive, or unique essential for research. Similarly, these researches often raised more questions than they answered, reinforcing idioms of cyclical development, or doubts over the nature of “progress.” In the construction of the Age of Mammals, valuations of progress and power were beset by uncertainty and threat.
The contested paleontological past rested on diverse perspectives. Indeed, rather than consider paleontology and the study of fossils as a single discipline, we should instead regard it, especially in its nineteenth-century form, as a linking field connecting many ways of knowing the natural world. While the nineteenth century has often been presented as a key period for the forging of modern disciplines, this was a difficult process.7 Relations between different branches of knowledge were close, and fossils linked studies of the earth and minerals with the natural history of plants and animals. Since the inception of the field, there has been a constant tension around the extent paleontological research is a geological subject, a biological or natural history one, or something sui generis. These debates shifted across the nineteenth and twentieth centuries. David Sepkoski has discussed the rise of the field of paleobiology in the second half of the twentieth century, defined by researchers like Jack Sepkoski and Stephen Jay Gould, and the use of statistical methods to understand fossil records.8 A different form of self-conscious paleobiology developed in the 1900s through figures like Henry Fairfield Osborn, Louis Dollo, and Othenio Abel, declaring (in often politicized manners) that “paleontology is the zoology of the past.”9 Early comparative anatomists like Georges Cuvier and scriptural geologists like William Buckland were also concerned with understanding fossil creatures as functioning organisms and communities.10 These were all distinct projects, but showed similar attempts to relate the life of the past and present. Alongside these shifts, other scholars argued that the study of fossils should be primarily concerned with stratigraphy, with the presence of particular fossils allowing discernment of the age of rock strata—a process often connected with mineralogy and the search for
resources.11 These changing emphases were constantly negotiated, as fossils were used to debate the history of the earth and life.
Additionally, the study of fossils was not just an intellectual pursuit connected with what we might now call disciplines. Defining, locating, extracting, and analyzing fossils required practical knowledge and expertise. One very fruitful area of recent scholarship has examined how geology was enmeshed with the developing industrial economy and exploitation of coal, stone, metal ores, and oil, linking consciousness of deep time with economic processes.12 Excavating fossils required skills around digging, preservation, and transportation, often relying on miners, quarry workers, and similar laborers.13 Once specimens were taken to collections, considerable work was required to transform them into usable specimens. Paul Brinkman and Caitlin Wylie highlighted the importance of fossil preparators, whose technical expertise refashioned fragmentary, fragile fossils into workable scientific objects.14 Knowing fossils often drew as much from the craft skills of manufacturing, casting, and preservation as it did erudite scholarly approaches to animals and nature.
The mixture of knowledge and expertise within paleontology raises a further point. As Claudine Cohen has argued, paleontological reasoning is based “not solely on observation and rationality, but sagacity and intuition, fiction and imagination, also play a necessary role in its hypotheses.”15 Partly this followed the trajectory of paleontology being entwined with literary modes of representation (as examined by Ralph O’Connor), 16 and artistic work, with art and imagination becoming necessary to reconstruct fossils and represent them as living organisms and “scenes from deep time.”17 Imagination also conditioned the practice of paleontological science itself. Understanding how fragmentary remains could connect with modern animals, and presenting assemblages of fossils not as masses of bone or rock, but as the relics of lost faunas and floras, depended on imagination and conjecture. The field certainly drew from detailed typological methods and claims of “objectivity,” and some aspects showed the drive to mechanical reproduction and discipline in nineteenth-century science discussed by Daston and Galison.18 However, given the gaps in the fossil record, distance in time, and strangeness of the paleontological past, studies of fossils required imaginative and speculative leaps. While the appropriate limits of speculation were a constant controversy, the field was persistently imbued with imagination and creativity.
As well as linking disciplines, people, and ways of knowing the natural world, the study of fossils also linked places. Paleontology was a self-consciously globalizing subject, and the construction of the earth’s history was exactly that: the construction of a past which could accommodate the whole world. This global focus intermixed the ideological and material aspects of paleontology. Paleontologists sought to define the history of life across time and space, accumulating fossils and geological specimens from all over the world (while comparing them with the remains of modern animals and often humans). This built a vision of earth history defined by changes in life across different eras and between different places. Sometimes Indigenous, vernacular, or traditional knowledge of fossils, earth, and landscapes were engaged with, but more often these were subordinated, instrumentalized, or erased. The deep-time sciences worked and reworked a range of pasts and traditions around the earth, and incorporated them within their concepts.
Two types of location were particularly significant within the shifting geographies of fossil work. The first were field sites—the places where fossils were extracted. In the paleontological imagination, “the field” has a special status, often associated with remote and dangerous places—the badlands of the United States, the far reaches of Patagonia, and arid regions in continental interiors. These areas were certainly important for the study of fossils, and for ideologies around the paleontologist as a masculine field-worker, part scientist and part frontiersman.19 But possibly more important were mines, agricultural fields, infrastructural cuttings, and urban digs. One core theme in this book is that exploited fossil sites tended to be in places being integrated into new industrial, commercial, and agricultural relations, rather than regions extremely remote to Western scholars. These sites could be difficult to work in, and the challenges of the modern environment were persistent features in excavation accounts. But fossil work almost invariably followed economic exploitation. Paleontology was a self-consciously “frontier science,” although it was a medium- to latestage entrant onto frontiers, using techniques and infrastructure set up by expanding political, economic, and colonial systems to assert conceptual and scholarly dominance over territories. Paleontology entered frontiers in a self-conscious manner, but did so when the balance had definitely shifted toward extraction.
The second major sites were central collections. The study of fossils depended on accumulation of material from across time and space. This was
partly due to the rhetoric and practices around fossil work. An emphasis on analysis and comparison of specimens meant that centralization was critical to making sense of the past. As John Pickstone has argued, the museum collection, far from being secondary to laboratories and universities, developed over the eighteenth and nineteenth centuries as an important expression of new collecting and ordering modes of science.20 Paleontology was a field centered on these institutions and ways of knowing. However, collections were sites of conflict and confusion as much as places of authoritarian dominance.21 Who within the collection had authority to own, interpret, and display specimens was not an easy question to answer. And the role of other institutions in knowing the fossil past, in particular universities, private collections, and commercial operators, was often contentious. The world of collections was fractious, both among different collections and with other sites of knowledge.
Paleontology depended on relations between field sites and collections. Yet these two places were more clusters around which relationships could be consolidated, rather than binary poles or clearly identifiable centers and peripheries. Managing fieldwork, moving between the field site and collection, and negotiating for access and material contested the power of centers and built new ones. Much of this book examines the challenges and strategies of science being worked at a distance, whether through the organization of expeditions, managing collaborators, and transporting and preserving material. Control over field sites consolidated authority in particular places, especially as new scientific institutions developed in regions regarded as significant. Authority often varied depending on access, proximity, funds, and tradition. These relations conditioned how paleontology was undertaken and the concepts underlying the field.
The deep-time sciences therefore offer almost an ideal case study to understand how different forms of knowledge and claims to authority interacted and moved across the nineteenth and early twentieth centuries, a research problem most notably expressed through James Secord’s contention that knowledge is produced through communication and circulation among different social and geographic contexts.22 These transfers were not easy and depended on fierce debate and contestation. The history of paleontology allows us to get to grips with Fa-ti Fan’s contention that “what is called ‘circulation’ may have been really a series of negotiations, pushes and pulls, struggles, and stops and starts.”23 It allows us to see movement across
“lumpy” networks of power and exchange, and the connections of scholarship with hierarchies of knowledge and authority.24 Global and totalizing messages were assertions of power from particular places, but also opened space for other voices—and blockage and conflict were just as important as circulation and exchange.
Understanding the Mammal Emphasis
My focus on the history of research on fossil mammals sets this book apart from most works on the history of nineteenth-century paleontology. Apart from broad studies examining the overall establishment and implications of geological time, most histories have taken dinosaur paleontology as the core focus of the field. A range of works have shown—in excellent detail—how dinosaurs and other Mesozoic reptiles captured public imaginations across American and European societies. For example, Paul Brinkman’s Second Jurassic Dinosaur Rush discusses how dinosaur fossils were key to building scientific institutions in the United States, Ilja Nieuwland’s American Dinosaur Abroad examines the transfer of dinosaur fossils across varied political and cultural contexts in Europe and the United States, Lukas Rieppel’s Assembling the Dinosaur draws out the connections between dinosaur paleontology and Gilded Age American capitalism, and Richard Fallon’s Reimagining Dinosaurs has shown how relations between science and literature were key to constructing the dinosaur as a transatlantic icon.25 Meanwhile, the Dinosaurs in Berlin project has examined the early twentieth-century German-led excavations at Tendaguru in modern Tanzania to consider the links among paleontology, colonialism, and international politics.26 We therefore have a large literature showing how dinosaurs became important icons of prehistory, especially in Anglo-American contexts in the late nineteenth and early twentieth centuries. This work emphasizes the relations between science and popular culture; transfer across national, local, and colonial contexts; and political and economic power.
While a great deal has been written about the impact of dinosaur paleontology, the equally prominent nineteenth-century focus on fossil mammals has been much less studied. The few exceptions are popular works27 and books dealing with the reception of iconic creatures, particularly mastodons, mammoths, and giant sloths.28 As well as missing a crucial focus within the history of paleontology, the relative lack of work on engagement with fossil
mammals has obscured important aspects of the impact and role of the deep-time sciences. Presentations of dinosaurs tended to emphasize their strangeness and monstrosity, with accounts of their “grotesque,” “ugly,” and “ferocious” characters.29 Similar terms were used for some extinct mammals, particularly early or large forms that seemed unrelated to modern organisms. Yet other prehistoric mammals were presented as comparable or ancestral to modern animals, explaining the origins of modern faunas and landscapes. Indeed, Rieppel’s Assembling the Dinosaur includes an entire chapter implying that scientific interest in mammals, and valuation of “mammalian traits” of sociability and intelligence, was much greater than attention given to dinosaurs.30 The history of the mammals gives us a deeper view of paleontology’s cultural role: life’s history was not just about weirdness, size, and monstrosity, but about empathy and linkages across the eras. Fossil mammals could show strange “extinct monsters,” but also held the key to understanding the modern world and the forces driving life.
A focus on fossil mammals also gives new insights into the geographies of paleontological work. That histories of dinosaur paleontology orient around Britain, the United States, and to a lesser extent Germany does not just reflect the interests of historians, but the main places where dinosaur paleontology was conducted in the nineteenth and early twentieth centuries. Richard Fallon discusses the popularization of the term dinosaur as a decidedly US-British phenomenon.31 Fossil work on dinosaurs was often unusual, requiring well-resourced collections with access to the rare sites containing well-preserved dinosaur fossils. This has therefore focused the history of paleontology around a few large museums in a few countries, which—while certainly important (and are indeed often key players within this book)—were not the only significant places. The history of other branches of paleontology—where fossils were more abundant, more easily worked, and spread more widely around the world—gives a broader vision of where and by whom paleontological work was undertaken. While dinosaur paleontology was geographically uneven, fossil mammals formed the basis for extensive collections across Europe, the Americas, Asia, Africa, and Australasia.
Studies of fossil mammals were also about recent history and made the “natural” past relevant to the present, conditioning understandings of modern environments and animals. In recent decades environmental history has become a wide-ranging project, with large historiographies examining
human entanglements with nature and the construction of new hybrid environments, both metaphorically and materially.32 As Simon Schama has influentially stated, landscapes were imbued with symbolic value and connected with variously imagined pasts, as “landscape is the work of the mind. Its scenery is built up as much from strata of memory as from layers of rock.”33 The history of the deep-time sciences allows us to think about how these layers of rock were themselves understood as representing deep and resonant memories. The importance of the deep past to engagement with modern environments has recently been drawn out in some nineteenth-century case studies, especially by Pratik Chakrabarti in the case of India and Daniel Zizzamia for the American West.34 This book argues that these were not isolated incidents, but that the deep past permeated nineteenth-century engagement with the natural world. Where scientists and officials were concerned with making land “productive” through expanding agriculture, cutting through rocks to build roads and railways, or locating mineral resources like coal, knowledge of the deep past was critical to development. Long-term geological change was invoked to argue that modern environments were not static, but the latest phase of a much deeper series of eras. Past ages of lush forests, open oceans, or bountiful grasslands either laid down mineral resources or showed what the land could be like, if environmental conditions were managed.
The fossil mammals provided a history for the animal world, which raises a further point of intersection with the rapidly growing field of animal history, which contends that integrating nonhuman animals into historical processes allows us to see important issues in new lights.35 Animals have been shown as essential for nineteenth-century economies and social systems, deeply tied to urbanization, economic change, and imperialism, and highly conceptually significant, with animals becoming symbolic of environments and places or thought to embody particular moral values.36 Yet, strangely, histories of human–animal relations have rarely engaged with how the deep-time sciences affected engagement with modern creatures. Works in the field frequently refer to the impact of Darwinian evolution, theories of social development, and recent extinctions on human engagement with the animal world. But the construction of the long history of animal life is usually only obliquely touched on. Indeed, it is more common for works in both animal history and environmental history to discuss modern theories of the evolution of specific organisms or the paleoclimate of particular
environments, rather than consider how many of these evolutionary and developmental narratives were themselves constructed in tandem with the nineteenth-century transformation of the environment and animal world. An underlying theme of this book is that engagement with fossils was a central means through which environments and animals were understood in the nineteenth century, and reflections on deep time were deeply entangled with changing knowledge of the current natural world.
We can see how modern creatures were defined through their assumed developmental past if we consider some of the major reasons why so much nineteenth-century attention focused on living and fossil mammals. Indeed, the originary work in the field of animal history, Harriet Ritvo’s The Animal Estate, takes for granted that mammals were the main focus for Victorian observers, being the animals “with which people interacted most frequently and identified most readily.”37 More recently the excellent collection Animalia: An Anti-Imperial Bestiary for Our Times, examining entanglements between animals and the British Empire, devotes twenty-two of its twenty-six chapters to mammals, not only indicating historiographic emphasis, but the symbolic value of mammals.38 This value was partly due to perceived utility and familiarity. An 1891 British text described mammals as “the best known and undoubtedly the most important group of the animal kingdom,”39 and the French popular science writer Louis Figuier called them “the most important class of the vertebrates,” who “interest us because they supply the animal auxiliaries who are most useful for our nourishment, work, and the needs of our industry.”40 As the history of human–animal relations has shown, mammals had crucial social and economic roles: cattle, pigs, and sheep were raised at increasing scales for meat, wool, and leather; horses powered cities and agriculture; dogs and cats were increasingly kept as companion animals; and exotic creatures like hippos, elephants, tigers, and bears became symbols of particular parts of the world and were hunted for commodities like ivory, hides, and fur. Mammals were pervasive, both as living creatures and as dead objects. Paleontology and the transportation of fossils were based on the same currents of global and imperial commerce as the movement of extant animals and their by-products. The life of the past was bound with the life of the present in tangible and material ways. The prominence of mammals in the modern world was paralleled by their fossils. Mammal fossils were still rare, but considerably more common than the older remains of dinosaurs and other early reptiles and the usually
fragile fossils of birds (with the notable exception of robust flightless birds like the moa of New Zealand).41 Mammal fossils were also found throughout the world, from relatively recent geological periods. As a result, there were simply more mammal fossils in better states of preservation to be collected and studied than there were fossils of reptiles and birds. Large comparative collections were built up in numerous places. While it has been argued that this long knowledge of fossil mammals took away from their novelty and “by the end of the 1820s . . . hyaenas were old news, and a procession of bizarre extinct reptiles lurched into the limelight,”42 it also meant fossil mammals could be used to engage with large problems, particularly those around development, variation, and distribution, at a time when scientific authority was often based around the accumulation of large amounts of material.
Of course, there were even larger collections of fossil invertebrates and fish, which were critical for forming ideas of development. 43 However, these never acquired the prestige of fossil mammals, for important cultural reasons. Nineteenth-century natural historians looked on mammals as the highest animals, at the summit of natural progress and exceeded only by humans (whose place within the mammals was itself debated). Histories of human–animal relations have often highlighted an overemphasis on charismatic mammals in animal studies, in contrast to the insights to be gained from studying human interaction with insects, fish, and microorganisms. 44 This book regards this mammal emphasis as an entry point rather than a problem. The privileging of the mammal derives from nineteenth-century views, where nature and human society were understood through hierarchy and progress.45 Paleontology was crucial for this alignment, as life’s history was used to show improvement up the scale of creation. While the regularity of progress was contested, the notion that animals could be arranged into a hierarchy of invertebrate, fish, amphibian, reptile, mammal, and human (with birds being difficult to place) was consistent. And the pervasiveness of scale-thinking made mammals crucial for defining natural progress.
Ideas of hierarchy within the mammals were complicated by older notions of the “chain of being.” The idea that all creation could be ordered into a single schema, alternately called “the scale of nature” or “chain of being,” was a long-standing one in European culture (and also the history of ideas, where Arthur Lovejoy’s The Great Chain of Being is a founding work). 46 Nineteenth-century taxonomies had a variable relationship with this notion. The idea of a single scale was often criticized by naturalists
as a holdover from classical thinking. Yet discussions of nature constantly referred to connection, linkage, order, “high,” and “low.” Museum displays, textbooks, and encyclopedias of natural history would consistently follow chain-of-being arrangements, either starting at a notional summit with humans or primates and then moving down to the “lower” creatures, or starting with the “simplest” organisms and then ascending. Often assumed rather than overtly stated, the scale maintained a continued grip, and as Harriet Ritvo has noted, “reports of the death, or even the displacement, of the chain were greatly exaggerated.”47
The chain was complicated because mammals were not just defined as “high,” but as incredibly diverse. Nineteenth-century scholars constantly stated how mammals had a unity of form, but varied lifestyles, including swimming whales, flying bats, burrowing rodents, large and small predators, and herd-living ungulates. The American paleontologist William Berryman Scott wrote, “It is as though a musician had taken a single theme and developed it into endless variations, preserving an unmistakable unity through all the changes.”48 Mammals in their diversity represented the widest flowering within the natural world. They became central to debates over comparative anatomy, Darwinian evolution and its branching patterns, and how animals formed communities, either as “ecologies” or as part of the “economy of nature.” In reflections on mammals, progress and hierarchy were squared with diversity and variation.
A final point is that valuation of mammals rested on empathy and emotion. There was tremendous nineteenth-century debate over the relationships between humans and animals, but also persistent assumptions that mammals were close to humans. The notion of mammals as high in the scale of life was compounded by anthropomorphic characterizations, citing their intelligence, sociability, familial life, and complex emotions. The tremendous expansion of companion animals like dogs and cats and working connections with animals like horses, cattle, and sheep bolstered this perceived empathy.49 Mammals seemed to presage human capacities, and were regarded as easier to understand than birds, reptiles, and other creatures. Dolly Jørgensen, in her study of valuing “lost” species, highlighted the need to pay attention to emotional engagement with animals and environments, as much as scientifically “rational” factors.50 In the case of paleontology, the relationship between rationality and imagination, and the imposition of values on landscapes and creatures, was an emotive affair.
Mammals were therefore useful and good to think with for numerous reasons, with their assumed utility, abundance, hierarchy, diversity, and emotional resonances being particularly significant. Nineteenth-century paleontologists used mammals to create a deep history of progress and differentiation. Importantly, ancient mammals were not lost relics of a former age like the dinosaurs or trilobites. The Age of Mammals was recent enough to still be thought of as present in many parts of the world (even if often seen as under threat). Through focusing on the mammals, paleontology became not just about elaborating lost worlds, but understanding modern nature—even as it shifted, possibly into a new epoch.
Structure of the Work
This book therefore traces a large topic, examining how mammalian life was given a global history during the long nineteenth century. Selections must of course be made within this canvas. Geographically, the book has a center of gravity in Europe and North America, which (as work on the history of dinosaur paleontology has shown) were key locations for the elaboration of fossil worlds, the sites of large, often self-consciously universalizing collections, and core players within economic and colonial power structures. However, an emphasis on regions where fossils were found and how these were integrated into systems of knowledge brings in a wider geography. Examples from South America, Egypt, South Asia, and Australasia will be brought in as particularly important instances (although of course it must be noted that these were not the only places involved—further case studies on the Russian Empire, southeastern Europe, and eastern and central Asia would also be of great interest, but have mainly been omitted from this book due to limitations in my own linguistic abilities). Across these different places, we can see how the fossil world was elaborated across different geographies, the contestation between different places and actors, and how the fraught building of an Age of Mammals was linked to assertions of its importance to the present.
The book traces the elaboration of the Age of Mammals across four chronologically distinct sections. The first begins with the eighteenth-century redefinition of fossils and bones in the earth as the remains of lost creatures and indicators of ancient landscapes. This carries across three chapters examining particularly important systematizations of these ideas:
the definition of the mammals themselves (and how this was connected with studies of fossils and modern life); the construction of two particularly puzzling beasts; and the elaboration of lost faunas through the expansion of European power in regions regarded as “ancient,” most notably India and Greece. These chapters see the building of a new fossil world, in which colonial and scholarly authority redefined the history and nature of life. This worked in complex ways with other means of knowing, and while new concepts of deep time were certainly important, they often reworked older mythic ideas as much as replaced them.
The second section sees how the Age of Mammals became increasingly ordered and conventionalized in the mid-nineteenth century. It first examines, across two chapters, how important institutions were founded in western Europe and North America, which were major centers of accumulation, but also field sites which reevaluated the modern territory. The remaining two chapters have a more conceptual focus, first tracing how the Age of Mammals was imagined as a series of eras, and then how paleontology became based around searches for origins and distribution. Paleontology was consolidated as a field in the years between 1850 and the 1880s, but in a contested way. Common values around progress, dominance, and links between the modern and ancient worlds were present, but often in a wary manner; uncertainty and calls to action were just as significant as confident pronouncements.
If the second section tells a story of increased consolidation of paleontological work, the third examines the heterogeneity within the field from the 1890s to the 1910s. This was certainly a period in which large institutions and particular models of the development of life were in the ascendant. The first two chapters of this section trace how institutions around the new museum movement and models of linear evolution (dramatically illustrated by the evolution of the horse) became powerful organizing principles. However, the next four chapters examine the messiness of these processes and the potential for contestation in places that could be regarded as peripheral, but that used their positions to become central to paleontological discourse. Fossil work in Argentina (especially Patagonia), Australia, Egypt, and the American West show how varied actors could claim authority within international networks and over the history of mammalian life.
The book concludes by examining a range of reflections on the natural world in the years around 1900, with the First World War being a natural
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MOTOR DISORDERS.
Paralysis (Akinesis) is loss of voluntary or involuntary muscular movement through defective innervation.
Paresis is a paralysis which is partial in degree; power of motion is impaired but not completely lost.
Hemiplegia is the loss of voluntary motion in many muscles on one side of the face or body. In general hemiplegia, the following muscles are usually excepted: muscles of the tongue, of mastication, of the eye, of respiration, of the neck and trunk, generally and of the proximal part of the limbs. The hind limbs are usually most affected, and muscles that are most exclusively under the control of the will those dominated by the cortical centres of the brain. When due to a clot on the brain or degeneration it occurs on the side opposite to that occupied by the clot, on account of the motor fibres crossing at the anterior pyramids of the medulla. Hemianæsthesia is a rare attendant and when present is often on the side opposite to the hemiplegia. Sensory fibres cross in the spinal cord, and the lesion is probably spinal.
Crossed Hemiplegia is motor paralysis of certain cephalic nerves (3d, 7th, 5th, 6th, and 8th,) on the same side with the clot or lesion, and of the muscles of the trunk on the other side. The cranial nerves proceed to muscles on the same side as their origin, while filaments going to the trunk through the spinal cord, cross in the pyramids (motor), or spinal cord (sensory). In crossed hemiplegia, hemianæsthesia is common with both forms of paralysis on one side.
Spinal Hemiplegia has the face and head sound (except sometimes the iris), and half the body paralyzed on the side opposite to that on which the spinal lesion (clot) exists. If anæsthesia exists it is on the side opposite to the lesion and posterior to it—the sensory filaments crossing just before leaving the cord.
Paraplegia is loss of voluntary power of one transverse half of the body; usually the posterior, and affects the tail, and has coincident anæsthesia, being due to a spinal lesion. Anal and vesical sphincters may or may not be paralyzed according as the lesions implicate their
respective spinal centres or not. If there is neither anæsthesia nor vesical paralysis the lesion may be cerebral, in the paracentral lobes of both hemispheres (meso-vertix at the fissure of Rolando).
Monoplegia is a circumscribed paralysis, as of one limb, or on one side of the face, one group of muscles or a single muscle. It may be due to cerebral, spinal or nervous lesion. Cerebral monoplegias are distinguished by: 1st, initial spasm; 2nd, absence of anæsthesia; 3d, persistence of nutrition; 4th, paralysis greatest in the distal portion of the member.
Localized Paralysis is usually due to lesion of a nerve, and is both motor and sensory. If due to a spinal lesion it usually affects one or more groups of muscles. In case the lesion is in the nerve, be guided, in investigating it, by Van der Kolk’s law, that the sensory fibres are usually distributed in the skin corresponding to the muscles which receive the motor fibres.
Pseudo-paralysis occurs from muscular disease, injury, inflammation or degeneration and has no appreciable central nor nervous lesion nor anæsthesia.
Spasm (Hyperkinesis); abnormal violent muscular contractions with or without loss of consciousness.
Tonic (tetanic) Spasm is violent and continuous.
Clonic Spasm is rapidly intermittent:—Contractions and relaxations.
Tremor (trembling) consists in small, intermittent, involuntary contractions.
Hemispasm affects the face, or limbs, or both, on one side of the body and may precede hemiplegia.
Monospasm affects one limb, one group of muscles or a single muscle. It may be due to lesion of the brain, of the spinal cord or of the nerves. Thus it may imply commencing disease of the motor centres or tracts.
Spasms of the Eyeballs (rolling of globe to one side), and Spasms of the Eyeballs and Head, are important indications of apoplexy. They imply disorder (commencing irritation) of the cerebral motor areas. Advanced disease would probably determine hebetude, coma, drowsiness, or palsy. If epileptiform it turns away
from the lesion. If hemiplegic it turns toward the lesion and away from the paralysis. If lesion of the pons it turns away from the lesion.
Paraplegic Spasm is a tonic spasm, partial in degree, causing stiff, tetanoid (spastic) walk. In all four extremities there may be mixed paresis and contraction. This often attends on hemorrhage into the meninges.
General Spasms, convulsions as in Eclampsia, Epilepsy, Chorea, Tetanus.
Local Spasms may be rhythmic or not, in slight cases to be seen only in the eyelids or superficial muscles as twitching, and occur in neurasthenia, or in poisoning by strychnia, brucia and other motor nerve poisons.
Incoördination (Dyskinesis) is the lack of the harmonious balanced movement of the various groups of muscles. Coördination of movement is due to a special mechanism in the spinal cord, and extending forward through the medulla oblongata, pons, and crura cerebri to the floor of the third ventricle. In the form of ataxia (lack of power of muscular control) it is usually the result of degeneration (sclerosis) of the superior columns of the cord, of the medulla, pons or crura. It may occur from degeneration or destructive change in the cerebellum, or from disease or section of the posterior roots of spinal nerves, or finally from the action of certain narcotic poisons (ptomaines, toxins).
Staggering (titubation) occurs from lesions of the cerebellum, medulla or pons; also from alcohol, opium, and other narcotics.
Reflex Action. The normal stimulation of different functions, motor, secretory, circulatory, etc., depends on the nerve centres in the spinal cord, which are roused into action by a centripetal impulse derived from a distant part. Thus the balanced contraction of the different muscles which preserves the equilibrium of the body, depends on the apprehension by the nerve centres, consciously or subconsciously, of such contractions (muscular sense), and it is largely under the control of the will. Here three impulses act coördinately: 1st, the afferent impulse from the muscle to the nerve centre; 2d, the efferent impulse from the nerve centre to the muscle; and 3d, the inhibitory or controlling, voluntary impulse from the sensorium to the nerve centre involved. In another case, savory
odors, sapid flavors and masticatory movements cause a free secretion from the salivary glands. Again, the scratching of a dog’s breast causes him to move his hind limb as if he were himself doing the scratching. Again, the pricking of a limb causes the prompt, even if involuntary, contraction of its muscles to withdraw it from the source of irritation.
Morbid Reflex. Reflex action may be modified in various ways as the result of disease or injury. It may become excessive from irritability of the organ from which the centripetal impulse starts, or of the reflex centre in the spinal cord, or of the muscle or other organ to which the centrifugal impulse is directed, or, finally, from impairment of, or separation from the inhibitory centre in the cerebrum. It may be impaired or abolished from degeneration or destruction of any of the tissues just named, or of the conducting nerves which connect them to each other.
The contraction and closure of the pupil under light is a reflex act from the retina on the optic lobes, etc., and from these through the motor oculi to the iris. This reflex is lost and the iris fails to contract in: anæsthesia of the retina; atrophy of the optic nerve; disease of the optic lobe; superior (posterior) spinal sclerosis; disease of the motor oculi; or disease of the iris.
The lumbar reflex is lost in many febrile states in the horse, so that pinching of the loins fails to produce wincing, and this becomes a test of the active persistence of the disorder.
Encreased Reflex is often noticed when the parts, including the spinal reflex centre, are disconnected from the brain: as in lesions or disease of the cord in front (cephalad) of its reflex centre. Here the cerebral or voluntary inhibition is lost.
Reflex Tonic Spasm of muscles around a diseased or dislocated joint, or of those controlling its action, often affords a valuable means of diagnosis, the possibility of nervous, muscular and tendinous disease being excluded.
TROPHIC SYMPTOMS AND DISORDERS.
Degenerative atrophy, in hæmoglobinuria, laryngeal hemiplegia, neurectomy, nerve lesion, brain or cord lesion, lead poisoning, disuse. Dermatitis, ulceration, morbid secretion, polyuria, mellituria, albuminuria, poisonous milk.
Degenerative Atrophy. From section, disease, atrophy or degeneration of nerves or nerve centres, the muscles, which they normally innervate, waste, often to an extreme degree. As examples of this we see the atrophy of the triceps extensor cruris and other groups in hæmoglobinuria, of the intrinsic laryngeal muscles in roaring, of the muscles supplied in neurectomy, and of groups of muscles in myelitis, broken back, lead paralysis, and scapular muscular atrophy. True to the law of wasting of physiologically inert organs, the nerves are atrophied and degenerated, and often also the bones, joints and skin.
The degeneration of an active organ applies to the nervous tissues themselves. According to the law of Waller, the nerve fibre (axis cylinder), when cut off from its nutritive centre (cell body with nucleus) degenerates and ultimately perishes. The axis cylinder is a component part of the neuron, which includes also its continuation in the cell and nucleus, and when the latter, which is the source and origin of both nerve impulse and trophic control, is lost, the inactive axis of the nerve fibre degenerates. This law is now availed of in tracing the distribution of nerve filaments, the degeneration being found in those that have been cut off from their nerve cells while those that come into the nerve trunk from other sources, distal of the injury, maintain their integrity.
In addition to this peripheral atrophy, a degeneration central of the injury to the nerve is seen under certain conditions, but especially in intrauterine life. In such cases the atrophy may extend
up to and include the central nerve cells, causing a secondary central nervous lesion from an initial peripheral one.
By bearing these laws of nerve atrophy in mind, lesions that would otherwise be obscure, may be satisfactorily accounted for.
Eruptions and Ulcerations of Nervous Origin. Herpes or shingles in man is now recognized as a nervous disease, circumscribed to the distribution of given nerves and occurring unilaterally or bilaterally. Deep-seated dermatitis, vesicles, neuralgia, pain, itching and formication are common accompaniments. The whole is traced to disease of the ganglion on the posterior (superior) root of the spinal nerve distributed to the part. This establishes a principle, and in inscrutable and obstinate, circumscribed skin disease the veterinarian should see if it coincides with the distribution of one or more sensory spinal nerves.
Ulcerations are often caused by the lack of protection of a part after paralysis, thus perforation of the cornea will follow section or disease of the trigeminus. These may be prevented by carefully covering the part, and even cured by a fine protective covering like collodion.
Alteration of the Secretions often follow on section of the sympathetic trunks, that of the cervical sympathetic in rabbits causing excessive congestion of the facial skin, with exudation and scabby product, also profuse secretion of sweat, tears, and ear cerumen and dry, scaly skin.
Polyuria is determined by section of one point of the medulla behind the root of the vagus, mellituria by puncture between the vagus and auditory nerves (the hepatic vaso-motor centre), and albuminuria by a puncture in front of the latter. Impairment of the hepatic vaso-motor tracts in the spinal cord, or of the anterior or posterior cervical sympathetic ganglia, or of the first thoracic ganglion equally determines nervous mellituria.
Poisonous milk produced in hard worked mares, or over-excited dams of other species, causing dyspepsia, diarrhœa, arthritis or other trouble in the suckling, must be in part attributed to nervous disorder.
Practically all secretions and nutrition are largely under nervous control, so that modifications in quantity or quality can often be
These are necessarily much less obvious to the veterinarian than to the physician of man. Yet in certain cases they may be observed directly, and in others deduced from dependent symptoms.
Hyperæsthesia is a state of exalted excitability of any part of the sensory nervous apparatus.
Cutaneous hyperæsthesia is that condition in which the slightest touch gives rise to an instant and extreme response. Some nervously organized mares which are dangerously ticklish and irritable, afford physiological examples. The surface soreness and sensitiveness which exist in the febrile chill, in wounds, dermatitis and neuralgia give pathological examples. It is further seen in certain cases of meningitis (cerebral and spinal), spinal irritations, rabies, tetanus and neuritis.
Hyperæsthesia to cold is seen in neuralgia, rheumatism, the early stages of many fevers (chill), in myelitis, neuritis, nerve injuries, and in posterior (superior) spinal sclerosis.
Hyperæsthesia of the muscles may be noted in tetanus, muscular rheumatism and neuralgia.
Visceral hyperæsthesia is shown in many cases of spasms of involuntary muscles (colic, arrest of intestinal calculi, gall stones or urinary concretions), and in inflammation of serous membranes (pleurisy, peritonitis).
Paræsthesia. This is a painful or morbid sensation caused by a lesion in the central nervous structures or in the nerves, but referred by the sufferer to some peripheral organ over which such centre
presides. It may even be referred to an organ or part that has been amputated or otherwise removed. This may cause lameness of a kind to indicate suffering in a given muscle, tendon or joint, when the cause is purely central. In dourine, sexual acts are excited which have their real source in the nerve centres. The rabid dog snaps at imaginary flies in mid-winter, when such insects are only phantoms of his brain.
Pressure on a nerve trunk induces sensations of tingling, vibration, formication, heat, cold, and paresis, referred by the mind to the part to which that nerve is distributed, and when the pressure is removed these sensations recede in the order in which they came. This may explain some occult cases of lameness.
Itching may be a pure, persistent neurosis without any skin lesion. Treatment should then be addressed to the nervous system.
Anæsthesia, or absence of sensation, is in its degree partial or complete. The latter is familiar as occurring in parts the sensory nerves of which have been cut across, also in parts the sensory nerve or nerve centres of which have become completely degenerated. There is no response to the prick of a needle, the touch of a hot wire, to pinching or cutting. If the nerve remains intact as far as the spinal centres, reflex action may still occur, but the patient himself has no consciousness of this nor of the injury causing it. Accordingly, he makes no movement of head, ears, eyes, or other parts still dominated by the brain.
In partial or imperfect anæsthesia the response to irritation is less marked and may be even delayed. In some forms of central lesions the response to a prick may be delayed two, five, or ten seconds, or even more.
Anæsthesia causes awkwardness or uncertainty of movement, especially if the subject is blindfolded.
Anæsthesia may be induced by medicine, as in the general anæsthesia of etherisation, or the local anæsthesia caused by the topical application of cocaine or carbolic acid.
Analgesia, or insensibility to pain, may be present in cases in which ordinary sensations are still felt. It may be caused by cocaine, alcohol, and to some extent by carbolic acid.
Hyperalgesia is the opposite of this condition, and may be seen in certain irritable conditions of the nerve centres.
PSYCHIC SYMPTOMS AND DISORDERS.
Limitation in lower animals. Effects of age training, race heredity, individual and racial peculiarities, exhaustion, prostration, dementia, cerebral congestion, compression, degeneration, narcotics, ptomaines, toxins. Controlling absorption in another trouble. Delusions, hallucinations, vice, violence, œstrum, fatigue. Cerebral source of motions.
These have a much more restricted field in the lower animals than in man in keeping with the limitation of the mental faculties, and they may often be traced to demonstrated structural disorder. Yet some emotions of joy, fear or rage run very high and are comparatively unchecked by high mental development or mental training. The effect of training is, however, very marked in the more educated animals.
Age modifies by the sobering that comes from experience and habit. The frolics of puppies, kittens, lambs, foals and calves are in marked contrast with the sedateness and stolidity of old dogs, cats, sheep or cattle.
Training is seen in the educated horse which would have been panic stricken at sight of a locomotive, flag or floating paper, at the smell of a lion or bear, at the sound of a gun or drum, and which will now boldly face any one of these with no manifest tremor. The emotional puppy can be trained to soberly fetch and carry, to drive sheep or cattle without biting, to lie sentinel by his master’s property, to point at birds without seeking to catch them, or to carry shot birds without devouring them.
Race heredity comes from the training along the same lines in many successive generations. Thus the more domesticated breeds of dogs (shepherd, poodle, and greyhound) are very affectionate; other breeds (bull, mastiff, bloodhound) are lacking in this character. All
trained races take naturally to the occupations of their ancestors. Some (horses, cattle and sheep) are easily panic-stricken, (stampeded). Some (turkeys, roosters) are not easily stampeded. Some (skunks), having effective sources, of defence, have little fear of man.
Individual and racial mental dullness and torpor must also be recognized. Some are stupid and slow, others alert and quickly responsive. Some horses are not level-headed and become uncontrollable in difficult situations. Some dogs are so emotional as to endanger their lives from sudden heart trouble. Some horses, dogs and cats will pine and die when separated from their fellows or human friends. Extreme timidity, or sudden rage may be so marked as to constitute a virtual morbid phenomenon. Sluggish cerebral and mental action may result from exhaustion, prostration, or dementia; also from cerebral congestion, pressure and degeneration; or from poisoning by narcotics, ptomaines or toxins (opium, hyoscyamus, Indian hemp, dourine, milk sickness, etc.). It may come from profound absorption in another object, as when the rabid dog bears whipping without a howl.
Delusions or hallucinations are shown in the rabid dog snapping at flies, or attacking his friend or master as an enemy, as well as in other forms of delirium. Narcotics, such as opium, Indian hemp, etc., ptomaines, toxins, and (in dogs) essential oils cause delirium by acting on the nerve centres.
Vice in its various forms may become a genuine neurosis, the animal losing control of its actions.
Violence in the form of self-defence or aggression is seen in mares in heat, in bulls or stallions under sexual excitement, in animals roused by inconsiderate whipping, or in bulls looking on scarlet clothing.
Some high-spirited animals, under extreme fatigue from overwork, sometimes become violent but resume their docility under rest and food.
In all cases we must know the normal of an individual animal to enable us to properly appreciate any apparent deviation from the psychic norm. No less essential is it to take into account the environment and treatment of the patient.
With regard to localization of cerebral lesions, Sequin thinks emotions are probably generated in the basal ganglia such as those of the pons and thalami, while inhibition depends on the anterior cerebral cortical convolutions.
DIAGNOSIS, SYMPTOMS AND THEIR IMMEDIATE CAUSES. LOCALIZATION OF LESION IN SPECIAL SYMPTOMS.
Spasm, pain, numbness irritation. Paresis, paralysis, anæsthesia (constant) destructive lesions. Both combined variable symptoms, recurrent. Definite, fixed symptoms structural lesions, usually progressive. Symptoms, variable as to place, time, subsidence and recurrence functional lesions. Brain lesions. Pressure on brain pain, spasm, nausea, dullness, blindness, stupor, coma, palsy. Congestion and anæmia synchronous. Lesions of cortex. Encephalic lesions hemiplegia, with spasms, increased reflexes, spasms follow cranial nerves, vertigo, apoplexy, epilepsy, dementia, coma, little muscular atrophy, or dermal sloughing. Spinal lesions, paraplegia without spasm, reflex reduced or nil, follow spinal nerves, head symptoms less, much muscular atrophy, bed sores. Sensory and motor tracts, in crus cerebri, respiratory centres inspiratory expiratory, inhibition. Salivation, sneezing, coughing, sucking, chewing, swallowing, vomiting. Cardiac centres, accelerating and inhibitory. Vaso-motor centre. Spasm centre. Perspiratory centre. Pons. Corpora quadrigemini, crura cerebri. Thalamus, corpus striatum. Cerebellum. Cerebral cortex: in ass; in dog. Spinal lesions: lateral half section: central anteroposterior, vertical section: superior columns: inferior columns: cervical lateral columns: respiratory tract: glycogenic centre: pupillary dilator: cardiac accelerator; vaso-motor, sudoriparous: centre for anal sphincter: for vesical sphincter: genital centre: vaso-motor and trophic centres: muscular sense tract: superior column and Goll’s. Table of phenomena from cord lesions.
In Irritation of nervous organs the symptoms (spasm, pain, numbness) are usually intermittent.
In Destructive Lesions of nervous organs the symptoms (paresis, paralysis, anæsthesia) are usually constant. When irritation and destruction are associated the symptoms are variable and frequent. The characteristic symptoms of the two may coexist or succeed each other.
Structural Nervous Lesions have symptoms that are definite in their area of distribution, nature (spasm, paralysis) and permanency. Objective Symptoms predominate and the case is likely to be progressive and fatal.
Functional Nervous Diseases have symptoms of indefinite distribution, variable in character, with intermissions and spontaneous disappearances (as under marked excitement) and subjective symptoms predominate. They may, however, last for a length of time without change.
Localisation of Brain Lesions.
Lesions of the cranial nerves and their superficial and deep centres of origin need not here occupy attention. These may be studied in works on anatomy and physiology. Attention may be drawn rather to the remoter effects of ganglia which affect or control distant action, and to general pressure on the encephalon.
General Pressure on the Encephalon, whether through fracture of the cranium and depression of bone, by acute congestion, by blood extravasation, by inflammatory exudation, or by acute abscess, will cause pain, spasms, nausea, dullness, blindness, stupor and coma. After expulsion of the cerebro-spinal fluid from the cranial cavity, the increasing pressure compresses the blood vessels, reduces or interrupts the circulation and abolishes the functions in the parts deprived of blood. Thus congestion of one portion of the encephalon is usually associated with diminished circulation in another portion. Disorder in the first may occur from hyperæmia and irritation and in another part from a consequent anæmia.
Destructive Lesions of Cortex of One Cerebral
Hemisphere may or may not cause permanent symptoms, as shown by the passage of a crowbar through the front of the left hemisphere, yet the man survived for 13 years and showed no loss of intelligence, his disposition and character alone having changed for the worse. The one hemisphere may by itself sufficiently control mental acts, while the other lies dormant or may even have undergone degeneration.
Diagnosis of Encephalic and Spinal Lesions. The following may be taken as guiding principles:
Encephalic: Hemiplegic or bilaterally hemiplegic grouping of symptoms.
Spinal: Paraplegic grouping of symptoms.
Encephalic: Frequent contracture or spasms of paretic muscles.
Spinal: Paralysis more perfect and continuous.
Encephalic: Reflexes in affected muscles increased: Cerebral inhibition absent.
Spinal: Reflex abolished or reduced in parts the seat of the lesion.
Encephalic: Spasms in areas of distribution of cranial nerves (not spinal.)
Spinal: Spasms and paralysis follow distribution of spinal nerves.
Encephalic: Head symptoms frequent (vertigo, apoplexy, epilepsy, dementia, coma).
Spinal: Relative absence of head symptoms.
Encephalic: Comparative absence of marked muscle atrophy.
Spinal: Atrophy in special muscular groups.
Encephalic: Little tendency to form bed sores.
Spinal: Tendency to form sloughs and bed sores.
Sensory (Æsthesodic) and Motor (Kinesodic) Tracts in Encephalon.
In the crus and above, the sensory tract lies dorso-laterad of the motor tract, forming about one-fifth of the crus, and extending upward through a white layer bending inward to form an angle and finally diverging to the different cortical convolutions. The motor tract is mainly contained in the inferior pyramids of the bulb, and constitutes the median two fifths and basal two fifths of the crus. Without entering farther into this subject it will be observed that lesions of the outer layer of the crus and its radiating fibres may cause hemianæsthesia of body or head, including the eye, while lesions of the median and basal layers and radiating fibres induce hemiplegia of the head, tongue, fore limb, hind limb, trunk, etc.
Respiratory Centres, Inspiratory and Expiratory are in the floor of the fourth ventricle between the centres for the vagus and accessory nerves, and are directly stimulated by the CO2 in the blood. Secondary subsidiary centres are in the optic thalamus, in the corpora quadrigemini both anterior and posterior pairs, and finally in the cervical spinal cord, so that disorder of respiration may occur from lesions in these points as well as in the main oblongata centre.
Respiratory Inhibition and arrest depend on the vagus, the superior and inferior laryngeal nerves.
The Salivation Centre also lies in the floor of the fourth ventricle and stimulation of the medulla causes free secretion.
The Centres for Sneezing, Coughing, Sucking, Chewing, Swallowing and Vomiting are also seated in the oblongata, so that any one of these phenomena may come from a central irritation. In bulbar paralysis the loss of power usually extends from the tongue through the lips, cheeks, jaws, pharynx, larynx, to the respiratory muscles and heart. Coughing may be roused by irritation of the external auditory meatus, liver, stomach, bowels, or generative organs as well as from the air passages.
Cardiac Accelerating and Inhibiting Centres are both present in the bulb, the latter receiving its afferent impulse mainly through the vagus nerve. Stimulation of the vagi, anæmia of the bulb through decapitation or through tying both carotids, hyperæmia through tying of the jugulars, a venous state of the blood, and blows on the abdomen all slow or arrest the heart action. Digitalis or muscarin has a similar effect. The heart action is accelerated by febrile and inflammatory affections, by a high or low temperature by section of the vagi, by sipping of cold water, by atropine or curari, and by salts of soda. Potash salts on the other hand restore the inhibitory action of the vagi and lower the heart’s action.
The Vaso-Motor Center is also in the oblongata and the contraction of the vessels with increase of arterial pressure may ensue from afferent currents in the sympathetic nerve and many sensory trunks. The varying activity is seen in blushing, in the congestion of mucous membranes under rage or excitement, in the capillary contraction in the early stage of inflammation, in the second stage of capillary dilation, in angioma or nævus and in extensive congestions and hæmorrhages in different organs. The arrest of bleeding under fainting is due largely to the anæmia of this centre.
A Spasm Centre the pricking of which causes general convulsions lies in the medulla oblongata at its junction with the pons. This is excited by excess of carbon dioxide in the blood, by suffocation, drowning, by anæmia of the bulb from bleeding or ligature of the carotids, by venous congestion after ligature of the jugulars, or by the direct application to the part of ammonia carbonate, or salts of potash or soda. It may also be roused by afferent nervous currents from different peripheral parts (spinal cord, sciatic nerve, etc.).
A Perspiratory Centre is found in the medulla, on each side, which may be roused into action by diaphoretics (opium, ipecacuan, tartar emetic, Calabar bean, nicotin, picrotoxin, camphor, pilocarpin, ammonia acetate, etc.).
The Pons like the medulla is at once a ganglionic and conducting organ, and its lesions may lead to arrest of nerve currents generated above or below it, or to the failure to develop currents in its own centres. Stimulation of its superficial layers may be without effect,
but if this is carried into the centre epileptiform convulsions ensue. Lesions of one side of its posterior half cause facial paralysis on the same side and motor and sensory paralysis on the opposite side of the body (crossed hemiplegia). Lesions of one side of its anterior half cause paralysis in both face and body on the same side. This depends on the crossing of the fibres midway back in the pons, which cross again in the medulla (motor fibres) and in the spinal cord (sensory fibres). Lesions of the pons are liable to interfere with the functions of the trigemini, the oculo motor and the superior oblique, and to determine epileptic movements and loss of coördination of sensoriomotor movements. Lesions of the superficial transverse fibres (median cerebellar peduncles) tend to cause involuntary movements to one side.
Lesions of the Corpora Quadrigemina cause disturbance of vision, failure of the pupil to contract to light, blindness, paralysis of the oculo-motor nerves, and lack of coördination of movements. Stimulation of one anterior corpus causes rolling of both eyes to the opposite side, with, if continued, a similar movement of the head and even of the body (horse in mill, or index motion, or rolling on its axis).
The Crura Cerebri are conducting bodies but contain also different nerve centres. Lesions of one crus cause violent pain and spasm on the opposite side of the body, followed by paralysis. The oculo motor may be paralyzed on the same side, but the face and tongue on the opposite side, owing to the fibres crossing in the pons. There may be turning movements.
The Optic Thalamus transmits sensory currents to the cerebral cortex. Lesions in this organ cause sensory paralysis on the opposite side of the body. Afferent currents that do not traverse the thalamus cause reflexes only. It contains one of the roots of the optic nerve and its destruction will impair vision. Its injuries may also produce turning movements.
The Corpus Striatum transmits motor currents originating in the cerebral cortex. Lesions of its interior (lenticular nucleus) cause motor paralysis and sometimes anæsthesia on the opposite side of the body. Electrical stimulation of this nucleus causes general muscular contractions of the opposite side of the body. Irritation of the surface layers is painless and symptomless.
