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Life of the Cell
Philosophy & History of
Cell Research
A workshop at Egenis,
University of Exeter
April 23rd & 24th, 2009
•William Bechtel
•Thomas Cavalier-Smith
•Ohad Parnes
•Andrew Reynolds
Life of the cell: Philosophy & history of cell research
On April 23rd and 24th, 2009, at Egenis, University of Exeter, UK, a number of
issues related to cells and cell biology will be investigated from historical,
philosophical and scientific perspectives. Topics include:
•The cell as the epistemic and ontological unit of life
•The evolution of cells and modes of cellular organization
• Multicellular and symbiotic cell collectives in relation to cellular autonomy
• Connections between cell biology and contemporary systems biology
• Plant, fungi and insect cells that call standard cell theory into question
A pre-workshop reading list is available on the workshop website:
www.genomicsnetwork.ac.uk/ egenis/events/workshops/title,3800,en.html
Keynote speakers
William Bechtel (Philosophy, University of California, San Diego):
The Cell: Locus or object of inquiry?
Thomas Cavalier-Smith (Zoology, University of Oxford): The evolution of cells
Ohad Parnes (History, Central European University, Budapest): Agents as
cells: Conceptual and historical perspectives
Andrew Reynolds (Philosophy and Religious Studies, Cape Breton University,
Nova Scotia): The redoubtable cell
Speakers (Egenis, University of Exeter)
John Bryant: Plant form: Cell differentiation with and without walls
Steve Hughes: Plant form: Cell differentiation with and without walls
Commentators
Sabine Brauckmann (Science Centre, Tartu University, Estonia)
John Dupré (Egenis, University of Exeter)
Pierre-Olivier Méthot (Egenis, University of Exeter)
Staffan Müller-Wille (Egenis, University of Exeter)
Dan Nicholson (Egenis, University of Exeter)
Maureen O’Malley (Egenis, University of Exeter)
Contact
Saira Kidangan, Egenis Secretary
Byrne House, University of Exeter
St Germans Road, Exeter, EX4 4PJ, UK
Email: [email protected]
Phone: +44 (0)1392 269140
Workshop programme
Thursday, April 23rd
8.30-9.00 Coffee
9.00-9.30 Welcome and introduction John Dupré & Staffan Müller-Wille
9.30-10.30 William Bechtel The Cell: Locus or Object of Inquiry?
10.30-11.00 Coffee break
10.45-11.15 Dan Nicholson Commentary on Bechtel
11.15-11.45 John Dupré Commentary on Bechtel
11.45-12.00 General discussion
12.00-1.30
Lunch
1.30-2.30
2.30-3.00
3.00-3.30
3.30-4.30
4.30-5.00
5.00-5.15
Andrew Reynolds The redoubtable cell
Sabine Brauckmann Commentary on Reynolds
Coffee break
Ohad Parnes Agents as cells: Conceptual & historical perspectives
Staffan Müller-Wille Commentary on Parnes
General discussion
Evening
Drinks and dinner
Friday, April 24th
8.30-9.00
Coffee
9.00-10.00 Thomas Cavalier-Smith
The evolution of cells: Real history is messy and non-Platonic
10.00-10.15 Andrew Reynolds Commentary on Cavalier-Smith
10.15-10.30 Maureen O’Malley Commentary on Cavalier-Smith
10.30-10.45 General discussion
10.45-11.15 Coffee break
11.15-12.15 John Bryant & Steve Hughes (joint presentation)
Plant form: Cell differentiation with and without walls
12.15-12.30 General discussion (15 minutes)
12.30-1.30 Summary and roundtable
Led by Pierre-Olivier Méthot & Dan Nicholson
1.30
Lunch
Life of the Cell: Philosophy & History of Cell Research
A pre-workshop reading list is available on the workshop
website:
www.genomicsnetwork.ac.uk/egenis/events/workshops/title,3800,en.html
Titles and abstracts
The Cell: Locus or object of inquiry?
WILLIAM BECHTEL
Department of Philosophy and Interdisciplinary Programs
in Cognitive Science and Science Studies
University of California, San Diego
The adoption of the name “cell biology” in the middle years of the 20th
century for a field of inquiry suggested the privileging of cells as objects of
inquiry. The term was chosen to supplant the older term “cytology” to
reflect the productive confluence of techniques—electron microscopy and
cell fractionation—that enabled an integrated investigation into cell
structure and function. In fact, however, in important respects the cell was
soon left behind as research decomposed cells into organelles and
systems of enzymes and focused on these. For some theorists, such
reductionistic inquiry is synonymous with progress. But is the cell now just
a locus of inquiry, no longer important as an object in its own right? The
growing appeals to systems in biology suggest its continued importance as
an object of inquiry. The decomposition into parts and operations is being
complemented by recomposition in which the interactions between
components, often dynamic, become the focus of inquiry. For some
purposes researchers are recognizing the need to situate the cell in its
environment to understand operations within it. For illustration, I will appeal
to research on circadian clocks in which the enormous success of
research decomposing individual cells that maintain circadian oscillations
into genes and proteins in the 1990s is complemented by research
recomposing systems within cells and research situating individual cells in
larger networks. The cell remains not just a locus but also an object of
inquiry.
Life of the Cell
Titles and abstracts (continued)
The evolution of cells: Real history is messy and non-Platonic
THOMAS CAVALIER-SMITH
Department of Zoology, University of Oxford, South Parks Road, Oxford
OX1 3PS, United Kingdom
I shall discuss four main questions. First, the historical role of studies of
protozoa and unicellular algae in the early history of the cell theory (mainly
first half of 19th century). This focuses on recognition of the nucleus and its
sphere of influence and of cell lineages as key units for much of biology.
Second, the long drawn out, often confused, recognition that bacteria are
structurally radically different from, yet ancestral to nucleated cells. Some
have held that we should therefore not treat bacteria as cells. But we
usually do. To unify both types of cell into a single concept we must regard
a cell as a holistic assemblage that grows and divides as a result of the
integrated activity of five kinds of entity: bounding (and optionally internal)
membrane(s); genes constituting one or more chromosomes (DNA
molecules); a cell skeleton; catalysts; and a pervasive watery milieu
containing mineral ions and small organic molecules. Third, I shall give
some microbial examples of the fuzziness of the distinction between cells
and syncytia and the non-text-book nature of many body plans. Fourth, I
shall discuss the permanent evolutionary merger of distinct cells to form
radically new chimaeric supercells, with special reference to the question
when an obligately endosymbiotic foreign cell makes the transition to an
integrated cell organelle, as in the origin of mitochondria from purple
bacteria, of chloroplasts from cyanobacteria, and of the exceedingly
complex chromalveolate cells that arose when a biciliate protozoan
enslaved and grossly modified a red algal eukaryotic cell. In so doing I shall
touch on a variety of issues of possible historical or philosophic interest,
including the idea of membrane heredity, often arguing that real history and
biology are messy and often excessively oversimplified for didactic or other
reasons. Yet the purpose of science and philosophy is to oversimplify boldly
but quasi-realistically.
Life of the Cell
Titles and abstracts (continued)
Agents as cells: Conceptual and historical perspectives
OHAD S. PARNES
Associate Professor
History Department
Central European University
Budapest
And:
Head of Research Group: History of Heredity
Zentrum für Literatur- und Kulturforschung
Berlin
I have argued elsewhere that contrary to common belief the ‘discovery’ of
the cell theory by Theodor Schwann in 1838 was not so much a matter of
better microscopy, but a direct result of an attempt to provide a mechanisticlike explanation of physiological processes in terms of their specific agents –
namely cells. At least since the beginning of the twentieth century, cells
seem to have lost their special role as agents of physiological or
pathological processes. In genetics, the agency of heredity has been located
first in chromosomes, then in genes and later in the molecular structure of
DNA. In pathology, the focus has similarly shifted from cells to their
components – e.g. the interaction with viral DNA/RNA in infection. At the
same time, other areas of biomedicine have favoured explanatory schemes
in which the cell is but an actor within a system, and where the agency is
ascribed to the behaviour of the system as a whole, not to the activity of
single cells (or their components) – here the most notable examples are
from neurology and immunology.
And yet, exactly hundred and seventy years after the publication of Theodor
Schwann’s work, there seems to be no way of relinquishing cells in
biomedical explanations. My talk will be an attempt to address this enigmatic
role of the cell in modern biomedicine: Is the cell in the 21st century merely
a morphological unit? To what extent has it retained its original role as an
agent of life and disease? Is there a place for cells also in explanatory
schemes where agency has been exchanged for reactivity? And finally:
Does it make sense to talk about one cell concept in modern biomedicine or
is it the case that different disciplines are employing different notions of cells
(e.g. immunological cells, neurological cells, microbiological cells, etc.)?
Life of the Cell: Titles and abstracts (continued)
The redoubtable cell
ANDREW REYNOLDS
Department of Philosophy and Religious Studies
Cape Breton University
From its first introduction the cell theory – the thesis that all life is situated
within a fundamental morphological and physiological unit, typically of
microscopic size – has faced criticism. Yet despite frequent charges of its
inadequacy the cell theory has (to borrow a line from the French philosopher
Gilson) continued to bury its undertakers. Why? What is it about the cell
concept that provides it with this redoubtable quality? (The urge to make a pun
here is irresistible, since redoubtable could also be construed to mean always
subject to doubt.) My talk will look at the history of criticisms of the cell
doctrine in an attempt to identify why it is that despite its oft-noted
shortcomings the cell concept continues to enjoy such vitality.
Plant form: Cell differentiation with and without walls
JOHN BRYANT and STEVE HUGHES
Biosciences & Egenis, University of Exeter
It is generally recognised that cell migration is not a feature of plant
development and that plant form is forged by anisotropic cell expansion
coupled to the reorientation of planes of division well in advance of mitosis
(Lloyd and Chan 2005) and also by asymmetric divisions. For a more
complete picture however, we need to add to this recipe the more subtle
developmental themes of apoptosis, or programmed cell death (Rogers,
2005), conductive tissues of intermediate cellular status (Holbrook et al., 2002;
van Bel, 2003) and the nesting of cells within cells in the sporophytegametophyte transition. Using examples of phloem and xylem cells (with
walls), aerenchyma , the egg apparatus, and syncytial endosperm (without
walls) we will examine these developmental themes against the proposal of
Baluka et al., (2004) for a partial disaggregation of cellular space into nuclear
and peripheral components (cell bodies). In the case of syncytial endosperm it
seems most interesting that a regular zonal differentiation of mitotic rhythm
can occur among nuclei, setting up the endosperm structural axis in advance
of cellularization of the space itself (Boisnard-Lorig et al., 2001). We therefore
finish with a question - When is a cell not a cell? and with its corollary - When
is an entity that is 'not a cell' a cell?