It Happened: The primacy of organic form (To the memory of Professor Brian Goodwin)

Full text

123Attualità biologica / News and Views
BOZZE / PROOFS:
Dott. Silvano Traverso
RB
103 (2010), pp. 123-138 = pp. 16 = 8 x 2
I Revisione: Autore 09.09.2010 Restituzione:
II Revisione: – richiesta: 20.09.2010
– avvenuta:
Attualità biologica / News and Views
È ACCADUTO... / IT HAPPENED…
The Primacy of Organic Form
(To the memory of Professor Brian Goodwin)
Lev Beloussov
About a year ago, July 15
th
2009 at the age of 78 passed one of
the most original biological thinkers of a recent past, Professor of
Schumacher College (Devon, England) Brian Carey Goodwin (BG).
During most of his career he had the courage to go against a scien-
tific mainstream. This is, by my view, an enviable fate, permitting
to keep one’s own personality and self-satisfaction. As far as I
could see during my few meetings with BG, he was a very opened,
bright and optimistic person.
The aim of this essay is not to review in details all of BG’s con-
tribution to biology and, the more, to philosophy and sociology,
which was among his main interests in last years. Rather, I would
like to discuss the main points of BG’s disagreement with the bio-
logical “mainstream”. I hope that such a review would be of inter-
est for the modern readers, especially those of younger generations
which weren’t the witnesses of the first “Sturm und Drang” of just
born molecular biology about half of a century ago. At that time
BG started his scientific career after graduating in biology from
McGill University in Canada and then in Edinburgh University;
in between he took math from Rhodes School, Oxford UK.
The dominating view of that time can be adequately repro-
duced by the following citation, belonging to one of the founders
Rivista di Biologia / Biology Forum 103 (2010), pp. 123-138.

Attualità biologica / News and Views124
of molecular biology: “The whole plan of growth, the whole series
of operations to be carried out, the order and the site of syntheses
and their coordination, are all written down in the nucleic acid
message” (Jacob [1974]). Accordingly, another representative of
the first generation of molecular biologists, Nobel prize laureate
Monod considered the organisms as chemical machines whose
structure is generated by a process “strictly comparable to molecu-
lar crystallization” (Monod [1972]).
At that time only few persons were enough brave and compe-
tent to qualify these claims as a terrible oversimplification of a real
situation, based upon the ignorance of biological macromorphology
on one hand and of the rules regulating the behavior of the com-
plex systems on the other. BG was among this “splendid minor-
ity”. In this he was certainly influenced by his outstanding teacher
Conrad Waddington, who wrote ironically that the relations be-
tween the spatial structure of the proteins and organic shapes weren’t
more direct than those between the scaffolds onto which laid Mi-
chelangelo
1
while painting the Sistine plafond, and the paintings
themselves (Waddington [1961]). But it was BG together with his
few coworkers who developed consecutively such a view, heretical
at that time. Undoubtedly, BG’s mathematical education, rare for
biologists, promoted him to take this position. BG perfectly un-
derstood how far were non-linear systems, the only ones capable to
make new structures, from the popular images of tabula rasa, onto
which any “text” could be written according to an imposed pro-
gram (within the framework of the text allegories, a believing that
“the whole plan of growth” is “written down in the nucleic acid
message” is no more sensible than to claim that Lev Tolstoi’s “War
and Peace” is “written down” in the Russian (and to a small ex-
tent, in the French) vocabularies; why not, if all the novel’s words
are contained in these two vocabularies and what remains for the
author is just to put them in their proper positions – quite similar
to what is taking place in a developing organism?).
During his whole scientific life BG advocated a simple idea,
which however met as a rule a harsh opposition – that the forms
1
By a funny “slip of a pen” as the author himself recognized, in his authentic text
Leonardo da Vinci was mentioned instead of Michelangelo.

125Attualità biologica / News and Views
of organisms (including in the notion of form practically all the
macroscopic activities, having considerable spatial components, for
example playing) require their own fundamental theory, which
cannot be replaced by references to genes or to a natural selection.
He regretted that in Darwin’s way of approaching biological ques-
tions the “organisms… have faded away to the point where they
no longer exist as fundamental and irreducible units of life” (Good-
win [1994], p. IX). Contrary to what is claimed both by classical
and by neo-Darwinists, BG argued to shift the focus from “inher-
itance and natural selection to creative emergence” (ibid., p. XIII),
whose existence, even in inorganic nature, was approved by a
theory of a self-organization. Correspondingly, BG was among
the firsts who constructed several models representing morphoge-
netic processes as self-organized events. In a number of such mod-
els BG attempted to consider spatial patterns as unfolding of tem-
poral ones. This was his believed approach since his first book
about the temporal organization of a cell (Goodwin [1963]) in
which a heroic attempt was made to treat molecular biology in a
holistic way. By a peculiar coincidence, the first BG model de-
scribing how temporal oscillations can produce spatial patterns
(Goodwin and Cohen [1969]), was published in the same journal
issue as a much more popular Lewis Wolpert’s model of “positional
information” (PI) (Wolpert [1969]) aiming to resolve the same prob-
lem. In spite of a personal friendship with Lewis and, more impor-
tant, of some holistic features of PI model, BG refused to accept it
because it treated embryonic tissue as a passive (rather than a self-
organized) matter governed by a “central directing agency” provid-
ing PI. In 1989, after the end of Waddington’s Conference taking
place in Solignac, South France, I was a witness of a harsh discus-
sion on these topics between Wolpert and BG in a crowded train
Limoge-Paris, which lasted until the train reached Gare de Lyon. So
far as I could see, each of the disputants reserved their own opinion.
One of the major points of BG opposition to the biological
mainstream was his view upon the role of genes in morphogenesis.
He was often reproached to neglect their role. This was not true:
actually, his position was much more sophisticated: “Genes do
have some remarkable properties, but there is a definite limit to
what they can tell us about organisms… (Goodwin, p. 3). “Genes
year ?

Attualità biologica / News and Views126
don’t control; they co-operate in producing variations on generic
themes” (ibid., p. 128). The cue word here is “generic” which
should be regarded in this context as a derivative of a generative
field, a central concept in BG’s world outlook (he extended it also
to the social and cultural events). Being unable to find a precise
definition of this notion in BG papers, I asked him once to give it.
He answered immediately: “This is a domain of a relational or-
der”. I do not know whether BG published anywhere this defini-
tion, but I find it really brilliant by its brevity and embracing
power and tell it regularly to my students. The “relational order”
is indeed the state of permanent collective interactions between the
members of a given domain (let they be cells, inter- or intracellular
structures) by means of which they adjust their shapes, positions
and/or functioning. This idea is exactly opposite to that of Wol-
pert’s PI, postulating the obedience of mutually independent units
to a common external factor. Correspondingly, PI concept lacks
any properties of a self-organization, while BG’s generative field is
a self-organizing entity. Within such a framework, the genes ac-
quire the important, but nevertheless restricted role of parameters
of field equations. Although up to now in the overwhelming ma-
jority of cases the equations are still unknown, one thing is obvi-
ous: taken per se, outside of the equations context, the parameters
are not endowed by any definite meaning (information); they ac-
quire the latter only within the given equations context.
This view, hardly acceptable and difficult to understand even a
decade or so ago, is now for many times confirmed by the same
molecular biology whose claims made half a century ago were of
the opposite meaning. What we have in mind is a numerously re-
produced situation when the same (or highly homologous) genetic
factors and signaling pathways are involved into quite different
developmental processes, say, in the primary induction or in the
limb development (modern standard text-books are full of such
examples). Therefore, by enumerating all the genes active at the
given space/temporal location, we cannot tell anything about what
developmental event is taking place in this location (and vice versa).
And even more: as recently shown by growing embryonic stem
cells onto the substrates of different geometry and mechanical
properties, the changes in cell shapes, induced by the substrate

127Attualità biologica / News and Views
mechano-geometry, act as upstream factors of the genes expres-
sion, thus highlighting “cell shape itself as a driving factor in de-
velopment” (McBeath et al. [2004]). We in our group got similar
results as applying to the neuro-mesodermal bias in the induced
rudiments of Xenopus embryos (Kornikova et al. [2010]). A pri-
macy of macroscopic shaping upon microscopic machinery, so
chivalrously advocated by BG since long ago, became silently
transformed from scientific heresy to a widely accepted view. It is
quite clear now, that a still lacking theory of morphogenesis should
be essentially macroscopic, regarding the successive shapes as inter-
linked dynamic entities rather than mutually independent end-re-
sults of genetic activities and/or such factors as PI.
For me personally a most memorable event associated with BG
was our first meeting in turmoil Moscow at the height of Gor-
bachev’s “perestroika”. All our company (Osaka Group), including
BG, was full of hopes for a more free world and, consequently, for
a more honest and pluripotent science, opened to the views of
minority. Not all of these expectations were realized, but the seeds
planted at that and the earlier times continue to grow. While be-
ing in Moscow, BG together with Mae Wan Ho visited the lab of
Professor Anna Gurwitsch, daughter of the founder of morphoge-
netic field theory, Alexander Gurwitsch. He told her how high
Conrad Waddington evaluated her father’s works. Space-temporal
scientific links, so harshly ruptured for many decades, started to
restore! I am sure that for BG this was a particular realization of
his beloved idea of the entire world as a coherent space-temporal
continuum, a kind of a highest order generative field.
MAIN BOOKS BY B.C. GOODWIN
Temporal Organization in Cells. Acad. Press, London and New York 1963.
Analytical Physiology of Cells and Developing Organisms. Acad. Press, London, New
York, San Francisco 1976.
How the Leopard Changed its Spots. The Evolution of Complexity. Weidenfeld and
Nicolson, London 1994.
(in collaboration with G.C. Webster) Il Problema della Forma in Biologia. Armando
Editore, Roma 1988.

Attualità biologica / News and Views128
OTHER REFERENCES
Goodwin, B.C, M.H. Cohen [1969], A Phase-shift Model for the Spatial and Tem-
poral Organization of Developing Systems. J. theor. Biol. V(25): 49–107.
Jacob, F. [1974], The Logic of Living Systems. Allen Line, London.
Kornikova, E.S., T.G. Troshina, S.V. Kremnyov and L.V. Beloussov [2010],
Neuro-mesodermal Patterns in Artificially Deformed Embryonic Explants: A
Role for Mechanogeometry in Tissue Differentiation. Devel. Dynamics 239:
885-896.
McBeath, R., D.M. Pirone, C.M. Nelson, K. Bhadriraju, C.S. Chen [2004], Cell
Shape, Cytoskeletal Tension and RhoA Regulate Stem Cell Lineage Commit-
ment. Devel. Cell 6: 483-495.
Monod, J. [1972], Chance and Necessity. Collins, London.
Waddington, C.H. [1968], Does Evolution Depend on Random Search? In C.H.
Waddington (ed.), Towards a Theoretical Biology. 1. Prolegomena. Edinburgh
U.P., Edinburgh, pp. 111-119.
Wolpert, L. [1969], Positional Information and the Spatial Pattern of Cellular Dif-
ferentiation. J. theor. Biol. V(25): 1-47.
PUNTI DI VISTA / VIEWPOINTS
The Self-similarity of Trunk Metabolism
Dewu Ding and Xiangrong He
Since Barabási and his coworkers published their seminal paper
on the topological structure of metabolic networks (Jeong et al.
[2000]), metabolism has been widely investigated with complex
network theory (or graph theory, i.e., metabolic reactions are linked
by metabolites): from structure to dynamics to biological function,
and even to disease, medicine, etc. (Aittokallio and Schwikowski
[2006]; Ding et al. [2009a]).
At the end of the paper, in which the hierarchical organization
of metabolism is proposed, Ravasz et al. concluded “the metabolic
network has an inherent self-similar property” (Ravasz et al. [2002]).
Later, by considering the self-similarity of some real complex sys-
tems, Song et al. thoroughly chased the conclusion with quantita-
tive analysis (Song et al. [2005]). They found that many (not all,
but including 43 cellular networks) real networks are self-similar.
Here, self-similarity is a typical property of fractals which had

129Attualità biologica / News and Views
been widely extended to life sciences (Losa [2005], [2009]), it re-
lates to the fact that any part of the network looks like the whole one.
However, the metabolic networks used in Song et al. ([2005])
are adopted from Jeong et al. ([2000]). These metabolic networks
contain some current metabolites and small molecules such as
ATP, ADP, NADH and H
2
O etc., which do not participate in
biologically meaningful transformations (Ma and Zeng [2003]). In
a general way, when complex network theory (or graph theory)
based methods are used for analyzing metabolic networks, we will
exclude these metabolites and only consider primary metabolites
(e.g., glucose) (Zhao et al. [2006]; Ma et al. [2007]; Ding et al.
[2008], [2009b]; Ding and Li [2009a]). Herein, we present such a
study, we mainly investigate the self-similarity of trunk metabolic
network (i.e., without current metabolites in the study).
The metabolic networks used here are extracted from recent
reconstructed high-quality metabolic network models for 3 differ-
ent domains: Homo sapiens (human) (Ma et al. [2007]) for eukarya,
Staphylococcus aureus (Lee et al. [2009]) for bacteria, and Halobac-
terium salinarum R-1 (Gonzalez et al. [2008]) for archaea. We first
exclude current metabolites and then extract the giant strong com-
ponent (GSC) part of these models for the self-similarity analysis.
Generally, the self-similarity of a network could be quantita-
tively characterized by its fractal dimension (also called self-similar
exponent) d
B
, and d
B
could be calculated by well-known box cov-
ering algorithm according to N
B
~ pow (
ᐉ
B
, -d
B
), where:
ᐉ
B
is box
size (i.e., all of the distances between any two nodes in the box are
smaller than
ᐉ
B
), while N
B
= N
B
(
ᐉ
B
) is the minimum number of
boxes for covering fully the network (Song et al. [2005], [2007]).
According to the box covering algorithm, we get the relation
between the box size
ᐉ
B
and the corresponding number of boxes
N
B
for Homo sapiens (human), Staphylococcus aureus and Halobac-
terium salinarum R-1. Then following the above expression: N
B
~
pow (
ᐉ
B
, -d
B
), the fractal dimensions for them are 1.48, 1.22 and
1.64, respectively. These results show that, after excluding the
current metabolites, the trunk metabolism is also self-similar, but
the fractal dimension is remarkable lower than the ones with cur-
rent metabolites (average 3.5 for 43 metabolic networks by Song et
al. [2005]). Furthermore, similar to the past finding about average

Attualità biologica / News and Views130
path length for the 3 domains (i.e., the average path lengths of
eukarya and archaea are longer than the one of bacteria), we find
that eukarya and archaea also have a bigger fractal dimensions
than bacteria.
Department of Mathematics and Computer Science, Chizhou College, Chizhou
247000, China
E-mail: dw.ding@hotmail.com
ACKNOWLEDGMENTS
The authors would like to thank the anonymous reviewers for their valuable com-
ments. Support for this work is provided by Natural Science Fund of Anhui Educa-
tion Department (KJ2010B133) and Master Foundation of Chizhou College
(XYK200809).
REFERENCES
Aittokallio, T. and B. Schwikowski [2006], Graph-based Methods for Analysing
Networks in Cell Biology. Brief Bioinform. 7: 243-255.
Ding, D.W., Y.R. Ding, K.Z. Lu, et al. [2008], Robustness in B. thuringiensis Metabolic
Network. Rivista di Biologia / Biology Forum 101: 265-278.
Ding, D.W. and L.N. Li [2009a], Why Giant Strong Component Is so Important
for Metabolic Networks? Rivista di Biologia / Biology Forum 102: 12-16.
Ding, D.W., Y.R. Ding, L.N. Li, et al. [2009b], Structural and Functional Analysis
of Giant Strong Component of Bacillus thuringiensis Metabolic Network. Bra-
zilian Journal of Microbiol. 40: 411-416.
Gonzalez, O., S. Gronau, M. Falb, et al. [2008], Reconstruction, Modeling & Analysis
of Halobacterium salinarum R-1 Metabolism. Mol. Biosyst. 4: 148-159.
Jeong, H., B. Tombor, R. Albert, et al. [2000], The Large-scale Organization of
Metabolic Networks. Nature 407: 651-654.
Lee, D.S., H. Burd, J.X. Liu, et al. [2009], Comparative Genome-scale Metabolic
Reconstruction and Flux Balance Analysis of Multiple Staphylococcus aureus
Genomes Identify Novel Antimicrobial Drug Targets. Journal of Bacteriology
191: 4015-4024.
Losa, G.A. [2005], Do Complex Cell Structures Share a Fractal-like organization?
http://www.fractal.org/Life-Science-Technology/Fractal-like-structure.pdf
Losa, G.A. [2009], The Fractal Geometry of Life. Rivista di Biologia / Biology Forum
102: 29-59.
Ma, H.W. and A.P. Zeng [2003], Reconstruction of Metabolic Networks from
Genome Data and Analysis of Their Global Structure for Various Organisms.
Bioinformatics 19: 270-277.

131Attualità biologica / News and Views
Ma, H.W., A. Sorokin, A. Mazein, et al. [2007], The Edinburgh Human Metabolic
Network Reconstruction and Its Functional Analysis. Molecular Systems Biology
3: 135.
Ravasz, E., A.L. Somera, D.A. Mongru, et al. [2002], Hierarchical Organization of
Modularity in Metabolic Networks. Science 297: 1551-1555.
Song, C., S. Havlin and H.A. Makse [2005], Self-similarity of Complex Networks.
Nature 433: 392-395.
Song, C., L.K. Gallos, S. Havlin, et al. [2007], How to Calculate the Fractal Di-
mension of a Complex Network: The Box Covering Algorithm. J. Stat. Mech.:
Theory Exp. P03006.
Zhao, J., H. Yu, J.H. Luo, et al. [2006], Complex Networks Theory for Analyzing
Metabolic Networks. Chinese Science Bulletin 51: 1529-1537.
LIBRI / BOOKS
Un editoriale lungo trent’anni
Silvano Traverso
Dal 1980 ad oggi Rivista di Biologia / Biology Forum ha assistito alle
alterne fortune della biologia attraverso lo sguardo acuto di Giuseppe
Sermonti. Con la pacata prosa dei suoi editoriali, Sermonti contrappone-
va al fermento scomposto dell’ingegneria genetica e ai suoi facili entusia-
smi la prudenza, e alle buone novelle genocentriche il richiamo ad una
visione meno riduzionista, in grado di far fronte ai problemi che la bio-
logia del ’900 ha colpevolmente rimosso: il problema della forma, della
struttura, delle leggi della trasformazione biologica.
L’editore Lindau ha raccolto gli editoriali con cui Sermonti ha aperto
per 30 anni la sua Rivista: una sessantina di riflessioni che non hanno
perso né smalto né attualità.
La prosa mite di Sermonti non tragga in inganno: spesso ammanta di
graziosa forma contenuti forti, non di rado provocatori. Affermazioni
come “per me la scienza è come ogni altra arte, come la musica o la pit-
tura” se da un lato ben chiariscono la concezione sermontiana del mon-
do dall’altro innescano la miccia dello scandalo nella comunità scientifi-
ca. Personalmente non seguo Sermonti nei territori in cui la scienza ten-
de a sfumare nella poesia e nella religiosità, e sono immune alle accuse
che a lui si rivolgono: professo la laicità della biologia e non credo al dia-
logo scienza/fede. Nondimeno trovo pienamente condivisibili molte del-
le critiche che Sermonti da sempre muove al paradigma mutazione/sele-
zione e al genocentrismo. D’altro canto, le nuove evidenze scientifiche (il

Attualità biologica / News and Views132
crollo del dogma centrale, l’avanzata dell’epigenetica ecc.) cominciano a
supportare una visione meno semplicistica dell’evoluzione e in generale
della “logica del vivente”. Sermonti ha sostenuto fin da tempi ormai lon-
tani una visione “moderna” della biologia patendo paradossalmente l’ac-
cusa di non essere al passo con i tempi: un genetista scettico nel pieno
dell’era genomica. Molte delle sue critiche si stanno rivelando, a poste-
riori, corrette. Poco importa quale visione del mondo e quali credenze
extrascientifiche abbiano potuto favorire l’emergere di quelle idee.
Come sia davvero nata la “questione Sermonti” non è semplice da
capire. Egli stesso si interroga sulle cause dell’ostracismo che lo ha colpi-
to. Lo fa nella bellissima introduzione autobiografica che apre il libro:
“Oggi, prossimo alla soglia del mio cammino, provo a capire quale
delle mie opere mi abbia reso inviso all’establishment. Non la mia critica
al darwinismo, perché il ‘processo a Sermonti’ era già avviato vent’anni
prima del Dopo Darwin, all’uscita del Crepuscolo. Neppure lo stesso Cre-
puscolo, che era un saggio gentile inserito in una collana del ben colloca-
to editore Rusconi. Fu proprio Genetics of Antibiotics, con il quale ero
uscito dall’uovo come il brutto anatroccolo di Andersen, senza aver chia-
rito prima a quale specie appartenessi” (p. 18).
L’introduzione andrebbe letta da molti, in primo luogo proprio dagli
oppositori di Sermonti. Illustra bene la genesi del caso Sermonti in Italia
e palesa alcune delle dinamiche nascoste (alla Pulcinella?) del mondo ac-
cademico.
Ma forse il modo migliore per godersi il libro è dimenticare le pole-
miche e gustare gli editoriali per quello che sono: preziose riflessioni sul
mondo vivente, visto con gli occhi di uno scienziato antiscientista per il
quale, se posso tentare una sintesi, la prima abilità del biologo è saper
rimanere stupefatti davanti al dispiegarsi della vita.
Giuseppe Sermonti, Le delizie della biologia. Il problema della forma e la
retorica del DNA. Lindau, Torino 2010, pp. 266, € 19,50.
RISVOLTI / FLAPS
Massimo Piattelli-Palmarini, Jerry A. Fodor, Gli errori di Darwin. Feltrinelli,
Milano 2010, pp. 272, € 25,00.
In questo libro Massimo Piattelli Palmarini, biofisico e scienziato cognitivo,
e Jerry Fodor, filosofo del linguaggio e cognitivista, sostengono che il principio

133Attualità biologica / News and Views
darwiniano di selezione naturale e di progressivo adattamento all’ambiente non
è verificabile. Anzi, con grande probabilità, è sbagliato. Lo dimostrano i dati
più recenti della ricerca genetica, embriologica e biomolecolare. E lo dimostra
l’esame stringente della logica interna della teoria darwiniana. Sulla scia di
Stephen J. Gould e Richard Lewontin, i primi evoluzionisti a mettere in seria
discussione il principio di selezione naturale, Piattelli e Fodor processano
Darwin e i suoi seguaci più ortodossi. Oggi, sostengono, possiamo affermare
con certezza che i viventi evolvono. Quali siano però i meccanismi che innesca-
no il cambiamento è questione controversa e non ancora del tutto chiara. Atei,
materialisti, non sospetti di derive creazioniste, i due autori credono che non
esistano nella scienza discussioni “inopportune”. Al contrario, proprio nel nome
della scienza occorre discutere con chiarezza e onestà i presupposti, i riscontri e
le aporie di tutte le teorie scientifiche. Darwin e il darwinismo sono stati a lun-
go ritenuti fondamentali per comprendere la natura del vivente, ma non sono
un feticcio che non possa essere messo sotto osservazione critica.
Richard Dawkins, Il più grande spettacolo della terra. Perché Darwin aveva ragio-
ne. Mondadori, Milano 2010, pp. 399, € 22,00.
Nel 1859 “L’origine delle specie” di Charles Darwin scosse il mondo dalle
fondamenta. Darwin sapeva benissimo che la sua teoria dell’evoluzione avrebbe
provocato un terremoto, ma non avrebbe mai potuto immaginare che, un seco-
lo e mezzo dopo, la controversia avrebbe continuato a infuriare. L’evoluzione è
considerata un “fatto” da tutti gli scienziati autorevoli, e per la verità anche dai
teologi più illuminati, eppure milioni di persone continuano a negarla o per
ignoranza o per obbedienza a una religione, con risultati inquietanti. Richard
Dawkins si inserisce nel dibattito in corso e fornisce un’esauriente panoramica
delle prove scientifiche dell’evoluzionismo, prendendo in esame le varie discipli-
ne, dalla chimica alla biologia, dall’embriologia alla paleontologia, e le moderne
strumentazioni che contribuiscono a confermare sotto molteplici profili la realtà
dell’evoluzione e, dopo aver sfatato la leggenda degli anelli mancanti (in realtà
ne mancano sempre meno...), conduce il lettore lungo l’affascinante itinerario
di studi aperto da Darwin. E lo fa scavando in una miniera di evidenze scienti-
fiche: analizza gli esempi viventi di selezione naturale e i reperti fossili, gli oro-
logi naturali che hanno segnato le tappe del lungo processo evolutivo e le com-
plesse fasi di sviluppo dell’embrione, le dinamiche della tettonica a placche e i
meccanismi della genetica molecolare.
Matt Ridley, Francis Crick. Lo scopritore del codice genetico. Codice, Torino
2010, pp. 164, € 18,00.
La battuta più fulminante su Francis Crick è stata pronunciata da Oliver
Sacks, il celebre neurologo e divulgatore inglese: “La mente di Crick non si fer-

Attualità biologica / News and Views134
mava mai”. Un uomo poliedrico, curioso, entusiasta della vita e dei suoi segreti:
“Era un vagabondo del sapere. Parlava più forte e rapido di chiunque altro”
disse James Watson, il biologo con cui Crick condivise una delle scoperte più
importanti del XX secolo: la struttura a doppia elica del DNA e il meccanismo
alla base della sua replicazione. Un talento scientifico che Matt Ridley riesce a
cogliere in tutto il suo fascino e in tutta la sua poliedricità: le voraci letture in-
fantili, la laurea in fisica, la passione per la biologia, nutrita dal desiderio di sco-
prire la vera natura degli esseri viventi e l’interesse, sviluppato negli anni della
maturità, per le neuroscienze.
Mark Buchanan, Guido Caldarelli, Paolo De Los Rios, Francesco Rao, Michele
Vendruscolo (eds.), Networks in Cell Biology. Cambridge U.P., Cambridge
2010, pp. 280, £ 45.00.
The science of complex biological networks is transforming research in areas
ranging from evolutionary biology to medicine. This is the first book on the
subject, providing a comprehensive introduction to complex network science
and its biological applications. With contributions from key leaders in both
network theory and modern cell biology, this book discusses the network sci-
ence that is increasingly foundational for systems biology and the quantitative
understanding of living systems. It surveys studies in the quantitative structure
and dynamics of genetic regulatory networks, molecular networks underlying
cellular metabolism, and other fundamental biological processes. The book
balances empirical studies and theory to give a unified overview of this interdis-
ciplinary science. It is a key introductory text for graduate students and re-
searchers in physics, biology and biochemistry, and presents ideas and tech-
niques from fields outside the reader’s own area of specialization.
Rong Li, Bruce Bowerman (eds.), Symmetry Breaking in Biology. Cold Spring
Harbor Laboratory Press, Woodbury 2010, pp. 301, $ 135.
Symmetry breaking events are critical for the survival of living systems.
They are required for cell division, development, and movement in all organ-
isms from single-celled species to human beings. Moreover, in multicellular
organisms, symmetry breaking allows the generation of cells with different fates
and underpins the complex arrangement of tissues and organs achieved during
embryogenesis.
Written and edited by experts in the field, this volume explores how sym-
metry breaking occurs in biology and the roles of these events at numerous dif-
ferent levels. The contributors examine the mechanisms by which cells polarize,
divide asymmetrically, and produce asymmetric structures, providing examples
from bacteria, yeast, plants, invertebrates, and mammals.

135Attualità biologica / News and Views
Including discussions of the molecular basis of polarization mechanisms,
asymmetric division of stem cells during development, the generation of left-
right asymmetry of the body axis in mammals, and theoretical approaches to
symmetry breaking, the volume is a vital reference for molecular, cell, and de-
velopmental biologists, as well as physical scientists interested in how and why
symmetry breaking occurs in living systems.
CORRISPONDENZA / CORRESPONDENCE
Why Zebrafish?
Dear Editor,
once, the Nobel laureate Dutch ethologist and ornithologist Tinbergen
1
suggested that the answer of any “why” question in biology is essential. Below,
we are addressing the question with respect to zebrafish (Danio rerio).
Currently, several model organisms are commonly used for studying the
developmental biology, such as Drosophila and Caenorhabditis elegans, and
mammals, such as mice, rats and primates etc. However, there is a wide re-
search gap between the invertebrate and vertebrate model systems. In develop-
mental biology, the gap has been filled by using the zebrafish model
2
. Due to
transparent embryos and rapid organogenesis, this model has been used by the
development biologist. Most of the internal organs like heart, liver kidney and
intestine totally developed by 96 h post fertilization (hpf). Organs, cells, tissues
are visualized in vivo and investigated in real-time. Other than developmental
biology, scientists are using zebrafish model for biochemical pathways
3
, molecu-
lar pathways
4
, signaling pathways
5
, diseases mechanism
6, 7
and drug discovery
6, 8
.
Another advantage is that zebrafish has cardiovascular, nervous and digestive
systems which are similar to those of mammals. A high degree of conservation
exists between the human and zebrafish genomes (approximately 75% similar-
ity). The Sanger Institute is in the process of sequencing the zebrafish genome.
1
N. Tinbergen, Z. Tierpsychol., 1963, 20: 410.
2
A. Meyer, C.H. Biermann, G. Orti, Proceedings: Biological Sciences, 1993, 252:
231-236.
3
S.E. Stachel, D.J. Grunwald, P.Z. Myers, Development, 1993, 117: 1261-1274.
4
J. Alexander, D.Y.R. Stainier, Current Biology, 1999, 9: 1147-1157.
5
K. Dumstrei, R. Mennecke, E. Raz, Journal of cell science, 2004, 117: 4787-4795.
6
A.L. Rubinstein, Current Opinion in Drug Discovery & Dev, 2003, 6: 218-222.
7
C.H. Hsu, Z.H. Wen, C.S. Lin, C. Chakraborty, Curr Neurovasc Res., 2007, 4:
111-120.
8
C. Chakraborty, C.H. Hsu, Z.H. Wen, C.S. Lin, G. Agoramoorthy, Curr Drug
Metab., 2009, 10: 116-124.

Attualità biologica / News and Views136
Raw sequence totalling approximately 7.8 times the size of the genome is now
publicly available. Updated assemblies are generated twice a year. A complete
assembled sequence has already been published
9
. Due to above advantages,
zebrafish is the most important research tool through out the world today. It is
clearly reflected in the Pubmed data . At the beginning of 1980, very few zebra-
fish researches were reported in Pubmed, but by the beginning of 2007 zebra-
fish research was reported in 1665 papers. In March 2008-2009, we searched
the Pubmed database with the two words, ‘zebrafish’ and the year like “2009”
(Fig. 1). The figure shows clearly that interest on this subject through out the
world is rapidly developing.
Fig. 1 – The increase in the use of zebrafish research reported in Pubmed references
from the year 1980 to 2009.
9
Zebrafish Genome Resources [online], http://www.ncbi.nlm.nih.gov/ genome/
guide/zebrafish

137Attualità biologica / News and Views
Interestingly, this beautiful tiny fish is distributed throughout the stream of the
river Ganges in India, Bangladesh and some part of Nepal and Pakistan
10, 11, 12, 13
.
The results of two field surveys conducted in India
14
and Bangladesh
15
, when
taken together, provide the most comprehensive description of the habitat pref-
erences of this species to date. The stream of the river Ganges is the natural
habitat of zebrafish. McClure et al.
14
sampled six sites within the river Ganges
drainage in the state of West Bengal and Uttar Pradesh, both in India, and
found zebrafish in three of the six sites, which included rice paddy and the
quieter waters of two foothill streams
14
. In Bangladesh, Spence et al.
15
con-
ducted surveys at twenty three sites in the Ganges and Brahmaputra drainages
and found zebrafish in nine of these locations. In the Indian study, zebrafish
were found only in still or slow moving waters, including shallow ponds, of
which quite a good number were connected to rice cultivation.
Since this popular model animal has originated from India, Indian scientists
should have affection with this model animal. However, we searched the
Pubmed database with the two words, ‘zebrafish’ and “India”, and we noticed
only 28 papers on zebrafish from India. Actually this tiny beautiful fish is more
favorite in home aquariums in India. However, we appeal to scientists through
out the world (especially Indian scientists) that they should use this model for
research more and more.
Chiranjib Chakraborty
1
and Govindasamy Agoramoorthy
2
1
School of Bio Sciences and Technology, VIT University, Vellore, India
2
Department of Pharmacy, Tajen University, Yanpu, Pingtung 907, Taiwan
E-mail: drchiranjib@yahoo.com(CC); agoram@mail.tajen.edu.tw(GA)
10
A.K.A. Rahman, Freshwater fishes of Bangladesh, Zoological Society of Bangladesh,
Department of Zoology, University of Dhaka, 1989.
11
R.P. Barman, Rec. Zool. Surv. India. Misc. Publ., Occas. Pap., 1991, 137: 1–91.
12
P.K. Talwar, A.G. Jhingran, Inland Fishes of India and Adjacent Countries, A.A.
Balkema, Rotterdam, 1991.
13
A.G.K. Menon, Rec. Zool. Surv. India. Misc. Publ., Occas. Pap., 1999, 175: 234–
259.
14
M.M. McClure, P.B. McIntyre, A.R. McCune, J. Fish Biol., 2006, 69: 553–570.
15
R. Spence, K.F. Runa, M. Reichard, K.A. Huq, M.A. Wahab, Z.F. Ahmed, C.
Smith, J. Fish Biol., 2006, 69: 1435–1448.