Model and movement: studying cell movement in early morphogenesis, 1900 to the present

Abstract

Morphogenesis is one of the fundamental processes of developing life. Gastrulation, especially, marks a period of major translocations and bustling rearrangements of cells that give rise to the three germ layers. It was also one of the earliest fields in biology where cell movement and behaviour in living specimens were investigated. This article examines scientific attempts to understand gastrulation from the point of view of cells in motion. It argues that the study of morphogenesis in the twentieth century faced a major dilemma, both epistemological and pictorial: representing form and understanding movement are mutually exclusive, as are understanding form and representing movement. The article follows various ways of modelling, imaging, and simulating gastrular processes, from the early twentieth century to present-day systems biology. The first section examines the tactile modelling of shape changes, the second cell cinematography, mainly the pioneering work of the German embryologists Friedrich Kopsch and Ernst Ludwig Gräper in the 1920s but also a series of classic, yet not widely known, studies of the 1960s. The third section deals with the changes that computer simulation and live-cell imaging introduced to the modelling of shape change and the study of cell movement at the turn of the twenty-first century. Although live-cell imaging promises to experiment upon and represent the living body simultaneously, I argue that the new visuals are an obstacle rather than a solution to the puzzle of understanding cell motion.

Aristotle, Buddhist scripture and embryology in ancient Mexico: building inclusion by re-thinking what counts as the history of developmental biology

“…It is striking, then, that this Tibetan chart appears rarely to have been discussed in the context of science history, even while the challenge of visually representing the dynamic, three-dimensional problem of embryology has been considered so extensively (e.g. Ekholm, 2018;Hopwood, 2000Hopwood, , 2005Wallingford, 2019a;Wellmann, 2017Wellmann, , 2018. Even more striking is the early date of this Tibetan work, which is largely contemporaneous with that of Fabricius.…”

On the Ontological Foundations of Cellular Development

“…∀x (Obj(x) → ∃y (Proc(y) ∧ ∀z t u (exhib(x, t, u) ↔ procbd(y, t, u))) (8) There is a difference between snapshots of objects and process-boundaries: snapshots are taken from objects, never from processes. Presentials have two sources: they can be snapshots of objects (in this case we say that an object Obj exhibits a presential at a time-point of its lifetime), or can be contained in boundaries of processes.…”

“…In essence, a sequence of frames can be transformed into a video providing processual properties. Since the famous works of the photographer Eadweard Muybridge to study motion from a sequence of static pictures, the method of changing time scales via slow-motion or time-lapse/fast motion provided many insights in the processual properties of nature, and in particular into the properties of embryogenesis (8,9).…”

“…How can we extract knowledge from such data collections? To this end, we also need to develop and refine our concepts and theories to make sense of the intricate patterns we can observe (8,9). As state-of-the-art microscopy becomes widely available to the biology community (10), we need to establish structured and general schemes (11) concurrently to annotate and share the tracking results.…”

Gluing life together. Computer simulation in the life sciences: an introduction

“…She shows that the understanding of morphogenesis has faced a major dilemma right from its early investigation: representing form and understanding movement are mutually exclusive, as are understanding form and representing movement. Providing a solution to this dilemma only on face value, she argues, live-cell animations are visual simulations that obscure rather than advance the understanding of morphogenesis (Wellmann 2018). …”