Fig. – The famous frontispiece from Scilla’s treatise of 1670 defending the organic nature of fossils. The solid young man, representing the truth of sensory experience, shows a fossil sea urchin in his right hand to a wraithlike figure representing the former style of speculative thinking. With his left hand, the solid figure points to other fossils found in Sicily. The text proclaims: “Vain speculation undeceived by the senses.” (from, Stephen Jay Gould, “The Structure Of Evolutionary Theory”, The Belknap Press of Harvard University Press”, Cambridge, Massachusetts, 2002).
Exaptation: 1. The use of a biological structure or function for a purpose other than that for which it initially evolved. 2. An evolutionary process in which a given adaptation is first naturally selected for, and subsequently used by the organism for something other than its original, intended purpose. 3. Exaptations – Features (such as feathers) that evolved by selection for one purpose (such as warmth) and were later adapted to a new purpose (such as flight). [more]. Exaptive: to show exaptation – featuring it.
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22 June, 2009 at 11:23 am
Porfírio Silva
Peço desculpa pelo adespropósito, mas era para dar notícia: Prémio Lemniscata.
22 June, 2009 at 9:27 pm
jofr
The book from Gould has 1,400 pages, weighs 5 pounds and is unreadable. I tried to read it once, some chapters are stupefying and convoluted, others bloated, long-winded and hazy. His popular smaller books are much better. Gould was good in precise observations, and he has coined nice terms like “exaptation” and “punctuated equilibrium”, but theory was his weakness. I think he was the inspiration for Monty Python’s Anne Elk.
22 June, 2009 at 10:17 pm
Vitorino Ramos
Porfírio. Muito obrigado. Mas e agora? terei que colar aqui o selo?! Eu não conheço muito a blogfractalândia Portuguesa (já a conheci mais no passado pela altura da “formiga de Langton”) e é me dificil. Mas destacaria do meu blogroll aqui da esquerda, os seguintes blogs:
Manuel Lima http://www.visualcomplexity.com/vc/blog/
Pedro Fonseca http://contrafactos.blogspot.com/
Mónica André http://monicasjeans.blogspot.com/
Ciência Hoje – http://www.cienciahoje.pt/
Fátima Rolo Duarte – http://f-world-blog.blogs.sapo.pt/
Ivan Franco – http://ivanfranco.wordpress.com/
David Rodrigues – http://sixhat.net/
Ah… quase que esquecia. Como disseste, para ser fiel ao projecto o premiado deverá responder à seguinte pergunta: O que significa para si ser um Homo Sapiens?. Ok, aqui vai: 10^11 células neurais, que a única coisa que fazem é “estúpidamente” reforçar ou deprimir sinais, mas que deste modo por cooperação auto-organizada levam à emergência de comportamento optimal – entre outras as, ideias -, fazendo assim o melhor uso do ambiente exterior à sua própria pele!
22 June, 2009 at 10:27 pm
Porfirio Silva
Bom, este não é o formato que os inventores da corrente quereriam. Mas quem se importa com isso?
BTY: a tua resposta à questão do Homo sapiens é uma das “teorias” que eu mais urgência sinto em contestar, mas de momento não me sinto preparado (ou com forças) para isso. Dará, talvez no futuro, uma boa polémica entre nós.
22 June, 2009 at 10:59 pm
Vitorino Ramos
Olá Porfirio de novo. Eh eh! Bom, eu não tenho nenhuma teoria – acredita – sobre o Homo sapiens. É apenas uma brincadeira minha baseada no firing neuronal existente nessas 10^11 células (que é uma realidade, e é Booleana). E no Conexionismo, claro. De qq modo gostaria de ouvir o que tens para dizer. Espero então por isso um dia, com prazer. Não sei se daria polémica, mas pelo menos “food for thougth” daria. E se houver polémica, tanto melhor. Afinal duas vezes 10^11 células, são muito mais que o simples resultado da multiplicação!
27 June, 2009 at 8:17 am
Santosh
Can exaptation be common sense?
28 June, 2009 at 6:48 pm
Vitorino Ramos
(jofr) If you don’t like it, what should I say, really? Basically this a response to Dennet’s “Darwin Dangerous Idea”, where punctuated equilibrium was at the central core of the debate, so likewise, at least for me, I consider it a “must read”. All agree that theory was his weakness, but on the other hand we now have precise fossil data, coming from respected scientific authors. Metaphors aside, I will wait a little more before “burning it”. http://scholar.google.com/scholar?hl=en&lr=&q=%22punctuated+equilibrium%22+fossil+data
28 June, 2009 at 7:12 pm
Vitorino Ramos
Santosh, sorry to say but I’m puzzled with your nice short question. I am not a biologist. I would probably say: “No”. Common-sense would probably be more connected to collective self-organization (due to one of his features, among others: positive feedback – mimics, imitation) than to (single or not) evolutionary traits, even if they would be proven to be exaptive. Really do not know. While being threaten by a predator, much probably a flock of birds would achieve (emerge) common sense, just by mimics (check BOIDS). Anyway, I did have once used that word in the past, over the following strict context (while speaking of “Artificial Ant Colonies in Digital Image Habitats – A Mass Behaviour Effect Study on Pattern Recognition, http://chemoton.wordpress.com/2008/10/22/collective-perception-and-memory-in-face-of-a-sudden-change/ ) :
[...] In those experiments, the emergence of network pheromone trails, for instance, are the product of several simple and local interactions that can evolve to complex patterns, which in some sense translate a meta-behaviour of that swarm. Moreover, the translation of one kind of low-level structure of information (present in a large number) to one meta-level is minimal. Although that behaviour is specified (and somehow constrained), there is minimal specification of the mechanism required to generate that behaviour; global behaviour evolves from the many relations of multiple simple behaviours, without global coordination, and using indirect communication (through the environment). One abstract example is the notion, within a specified population, of COMMONSENSE, being the meta-result a type of COLLECTIVE-CONSCIENCE. Needless to say, that some features are acquired (through out the evolving relation with the habitat), being others inner components of each part. Though, what is interesting to note is that we do not need to specify them. Moreover, the present model shows important adaptive capabilities, as in the presence of sudden changes in the habitat. Even if the model is able to quickly adapts to one specific environment, evolving from one empty pheromonal field, habitat transitions point that, the whole system is able to have some memory from past environments (i.e. convergence is more difficult after learning and perceiving one habitat). This emerged feature of résistance, is somewhat present in many of the natural phenomena that we find today in our society. [...]
pp. 14-15, in “On the Implicit and on the Artificial – Morphogenesis and Emergent Aesthetics in Autonomous Collective Systems”, in ARCHITOPIA Book, Art, Architecture and Science, INSTITUT D’ART CONTEMPORAIN, J.L. Maubant, L. Moura (Eds.), pp. 25-57, Chapter 2, ISBN 2905985631 – EAN 9782905985637, France, Feb. 2002. ( http://www.chemoton.org/ref37.html )