… all caterpillars, as long as the adult insects have mated beforehand, emerge from their eggs…1
Maria Sibylla Merian (German, 1647–1717) was 32 years old when she published this statement, written in a period when most people believed that insects arose by spontaneous generation. Her text on the metamorphosis of silkworms was reinforced by her carefully etched image of a female moth laying eggs, and caterpillars hatching and feeding on a mulberry leaf (Plate 1 on p. 148). Raised in a family of well-known publishers, she was trained from an early age in painting, etching and engraving. In 1699, she traveled to Surinam to study neotropical insects, and she is today best known for her magnificently illustrated Metamorphosis Insectorum Surinamensium.2 Perhaps because of the attention drawn to the larger and more dramatic book on New World plants and insects, scholars have tended to overlook her earlier books on the less showy European organisms. However, these earlier ‘caterpillar’ (Raupen) books, even more than Metamorphosis, contain a wealth of insightful observations on interactions among the species portrayed – a cornerstone of the study of ecology.3
When I first read the preface to her 1679 book on European moths and butterflies, it took me by surprise. As a biologist exploring a 350-year-old natural history book, the more I read the more it struck me that this was the work of a diligent observer, who today would be described as an entomologist working in behavioral ecology. The perspective that I bring to this book is that of someone who, like Merian, spent years studying nature in the field and laboratory in an attempt to satisfy my curiosity about the wonders encountered. Like her, I have experienced both frustration and pleasure in this pursuit. Perhaps most importantly for this volume, I understand the challenges and the tremendous effort (and, occasionally, luck) required in working with live organisms – even if one has a camera rather than a paintbrush to record visual observations. When I first came across Merian’s work many years ago, what puzzled me most was that she had not been acknowledged as the earliest naturalist to combine biologically related plants and animals into one image.4 Her innovative compositions elevated insects in a new way; they were no longer merely objects to be collected and classified, but actors on the scene, and in a starring role. I am not the first to champion her contributions to natural history by any means, but it seems that some of the earlier voices have been forgotten or ignored, and Merian has received little mention in recent histories of entomology and ecology.5
In recent years, scholarship on Merian has shown an uptick, but much of this has emphasized her fascinating life story or her artwork. Some have described her as primarily concerned with the aesthetics of her images. Other scholars have promoted the idea that she was a religious woman who created her books with the first consideration of encouraging piety, and still others have emphasized her work as a part of her livelihood. These motivations were neither insignificant to Merian nor unique to her as a naturalist of the period, but like most of her male counterparts, she was driven primarily by a lifelong curiosity – in her case, about insects. My book was written with the expectation that closer reading of her translated 1679 Raupen book and further examination of her information-packed images of insects and their host plants will increase appreciation for the quantity and quality of ecological and behavioral observations that she made.
To understand the significance of Merian’s contribution to science, we must acknowledge that prior to Merian’s Raupen books, animal and plant images were segregated, and these different taxa usually were organized in separate volumes. Natural history studies by her contemporaries often focused on describing and cataloging organisms. However, the systematic ordering of insects was of little or no interest to Merian. After receiving butterfly specimens from English naturalist James Petiver, her response was that she “was not looking for any more specimens, but only at the formation, propagation, and metamorphosis of creatures, how one emerges from the other, the nature of their diet …”.6 Her initial curiosity about their diet sprang from necessity; she wanted to raise insects in order to paint them, and knowledge of their specific food plants was essential to successful husbandry. While some caterpillars will eat almost any herbaceous plant, most are very particular, and they do not survive if deprived of the foods they require. She was the first to write about the significance of this connection between insects and plants, and she depicted these associations in her images of metamorphosis. As exemplified by the cover image for this book, she typically arranged the life cycle of a moth or butterfly around a plant that served as food for the caterpillar. In so doing, she eschewed the traditional format of natural history books that isolated specimens on a page, such that the focus was entirely on their physical structure. Instead, her readers could see and read about how caterpillars were born, fed, grew, and metamorphosed into pupae and then adults. Just as importantly, her text and images were the earliest to show the effects that insects had on the plants that nourished and sheltered them. In addition to the innovative content in her books, she was unusual for her time in that she was responsible for almost every step in the process of production of the 1679 Raupen book: she conducted the research, wrote the text, made the images (both drafting the compositions and etching the plates), and was involved in the marketing.
My book was conceived to serve four primary purposes: to provide an English translation of Merian’s first scientific work (the 1679 Raupen book); to lay out in detail what went into the making of this volume; to analyze and discuss the scientific content of her book; and to address Merian’s place in the history of science. The complete title of Merian’s 1679 book, like many of its period, reveals much about the work: The wondrous transformation and particular food plants of caterpillars, wherein, by means of an entirely new invention the origin, food, and changes of caterpillars, worms, butterflies, moths, flies, and other such small creatures, together with their time, location, and characteristics, for the benefit of naturalists, artists, and garden lovers, are carefully investigated, briefly described, painted from life, engraved in copper, and personally published by Maria Sibylla Graff, daughter of the late Matthaeus Merian the Elder. Parts of this title seemed appropriate as chapter headings for the first part of my book, The Flowering of Ecology.
In the first chapter of part 1, Before the Transformation, I describe earlier natural history books, which contained the seeds of ecological thought, but portrayed plants and animals separately with little to no discussion of interactions among different organisms. An objective of this chapter is to establish the state of 17th century European knowledge on entomology in general, and lepidopterans (moths and butterflies) more specifically.
The second chapter, A Life Investigated, recounts Merian’s biography and relevant family background, focusing on what is known of her life through the time when she produced the 1679 Raupen book. This chapter describes the milieu in which she produced her work, the rich visual and intellectual culture of 17th century Frankfurt and Nuremberg, and the role of women in the artisanal workplace. Her interactions with other naturalists and collectors are addressed, as well as her unique manner of establishing her credentials and authority, while maintaining her position in society as a pious, traditional woman. Lastly, I discuss what I believe were the motivations behind her years of intensive study on insects.
The third chapter, Described and Painted from Life, explores the steps of Merian’s process in creating her book as far as they are known or can be extrapolated reasonably. I describe her work in the field and in her home ‘laboratory,’ and her working methods, such as the use of small painted studies to record the metamorphosis of insects. The organization of her caterpillar book is explained and I discuss the composition of the plates, and the ways in which the text and images work together to achieve her goals in presenting her findings on insects and their plant hosts.
In the fourth chapter, For the Benefit of Naturalists, I briefly describe the other books that Merian produced over nearly three decades. Central to this chapter is an analysis of the influence of her writings and images on subsequent natural history studies. Ultimately, her ecological compositions created a different way to view nature, and this format was copied so frequently that it became one of the standard ways of composing natural history illustrations. Finally, this chapter addresses possible reasons why the biological information in her work and its significance have been neglected by scholars in spite of her influence and the high regard in which she was held by her near contemporaries.
The second part of this volume, Maria Sibylla Merian’s Caterpillar Book, presents an annotated English translation of the complete 1679 Raupen book text integrated with my commentary. As described in the translation notes, Michael Ritterson and I have attempted to retain the flavor of Merian’s style and language, and we have adhered to English vocabulary that reflects what was known about insects and plants in her time. As in the original book, the text is accompanied by her images of the metamorphic stages of insects with the plants on which the caterpillars usually feed. My commentary provides an overview of the natural history content of both the text and images in her book, and I discuss the novel information in her accounts of the insects she raised and observed. Special attention is given to her study of factors central to ecological science, including her descriptions of environmental effects on insect development and abundance and observations on insect food choice and feeding behavior.
Merian published her books on insects at a critical point in European natural history studies, and the Raupen books and Metamorphosis changed how nature was described and portrayed. Almost two centuries after Merian’s death, the study of insect–plant interactions became a focal point in the growing fields of ecology and evolution, and thousands of papers and books have been dedicated to these critical relationships. Plants comprise more than half of the biomass on Earth, and insects are the most prevalent animals on the planet in terms of total biomass. Thus, plant–insect interactions are a key to understanding terrestrial ecology. Wherever there are plants, there are insects set on using them for their own devices, but conversely, many plants employ insects for their benefit as well, primarily as pollinators. Lepidopterans in particular show two faces to the world: the larval stages (caterpillars) are perceived primarily as destructive and by most, ugly or repellent, whereas adult butterflies and moths are often thought of as beautiful, flying through the landscape adding color and motion. Caterpillars are among the most ravenous and destructive herbivores in many terrestrial ecosystems, capable of consuming three times their body weight in a day. As such they are the bane of farmers and gardeners the world over, yet they are essential elements of many a food chain, eaten by countless other animals. The adult stages frequently serve plants as pollinators as well as food for other animals.
Merian as a naturalist and an artist had a life-long love affair with all stages of the lepidopteran life cycle. She pursued her passion for more than five decades, recording the food plants, behavior and ecology of roughly 300 species of insects and publishing four books on her scientific work. Much of what she described withstands the scrutiny of modern biology, and the number of original observations in her work are astounding in an era when most biologists focus on one or two organisms in their career. Her images of insects on plants create small dramas, drawing attention to these critical links in the ecosystem in a way that was revolutionary for her time. Merian’s years of work generated a fundamental shift in the trajectory of natural history studies, and it is well past time that this was recognized.
Merian, Maria Sibylla. 1679. Der Raupen wunderbare Verwandlung und sonderbare Blumen- nahrung. Nuremberg: M. S. Merian: preface.
Merian, Maria Sibylla. 1705. Metamorphosis Insectorum Surinamensium. Amsterdam: G. Valck.
Merian, 1679. Raupen and Merian, Maria Sibylla. 1683. Der Raupen wunderbare Verwandlung und sonderbare Blumen-nahrung … Andrer Theil. Frankfurt and Leipzig: M. S. Merian. Used here for the sake of simplicity, the terms entomology, ecology, biology, and science came into use long after Merian.
Etheridge, Kay. 2011. Maria Sibylla Merian and the metamorphosis of natural history. Endeavour 35: 16–22.
An exception, Frank Egerton includes Merian in his history of ecology with an account of her writings and biography. Egerton, Frank N. 2012. Roots of Ecology: Antiquity to Haeckel. Oakland, CA: University of California Press: 194–5. Merian is not mentioned in Worster’s foundational work, which like many histories of ecology, begins its focus in the 18th century. Worster, Donald. 1994. Nature’s Economy: A History of Ecological Ideas. Cambridge: Cambridge University Press.
Letter from Merian to James Petiver in London, dated 27 April 1705. Folio 70, Sloane 4064. British Library.