Ici THK

Natural Theology

To me, the Gaia hypothesis, or theory as some would have + it, owes its origin to a dual set of sources: the immense + success of the international space program that began with + the launch of Sputnik by the Soviet Union in 1957 and the + lively but lonely scientiﬁc imagination, inspiration, and + persistence of Jim Lovelock. Part of the contentiousness + and ambiguity attendant on most current descriptions of + the Gaia hypothesis stems from confused deﬁnitions, + incompatible belief systems of the sci- entiﬁc authors, + and inconsistent terminology across the many a¤ected + disciplines (for example, atmospheric chemistry, + environmental studies, geology, microbiology, + planetary astronomy, space science, zoology).

Anger, dismissive attitude, and miscomprehension also come + from the tendency of the human mind toward + dichotomization. In this limited summary whose purpose is + to draw attention to several recent, excellent books on + Gaia science and correlated research trends, I list the + major postulates of the original Gaia statement and point + to recent avenues of in- vestigation into the veriﬁcation + and extension of Lovelock’s original ideas. I try to + minimize emotionally charged rhetoric aptly indulged in + and recently reviewed by Kirchner (2002) and to maximize + the proximity of the entries on my list to directly + observable, rather than computable, natural phenomena. I + self-consciously align this contribution to a ﬁeld ignored + by most of today’s scientiﬁc establishment and their + funding agencies, one considered obsolete, anachronistic, + dispensable, and atavistic.

To me this ﬁeld in its original form, ‘‘natural theology’’ + that became ‘‘natural history,’’ should be revived with + the same enthusiasm with which it thrived in the 18th and + early 19th centuries. That age of exploration of the seas + and lands generated natural history in the same way that + satellite technology and the penetration of space brought + forth Gaia theory. In fact when Lovelock said, ‘‘People + untrained ... do not revere ... Geosphere Bio-sphere + System, but they can ... see the word Gaia embracing both + the intuitive side of science and the wholly rational + understanding that comes from Earth System Science’’ he + makes a modern plan for the return to the respected + natural history, the enterprise from which biology, + geology, atmospheric science, and meteorology had not yet + irreversibly divorced themselves. Is he not explicit when + he writes, ‘‘We have some distance still to travel because + a proper understanding of the Earth requires the abolition + of disciplinary boundaries’’? For the science itself, + although precluded today by administrative and budgetary + constraints, the advisable action would be a return to + natural history, the status quo ante, before those + disciplines were even established.

Sexualité et commerce génétique planétaire

Les hommes exploitent l'énergie des combustibles fossiles vieux de millions d'années comme le charbon, le pétrole et le gaz naturel, ils n'ont pas encore puisé dans des gisements d'information vieux de plusieurs milliards d'années. La micro-électronique de la photosynthèse, le génie génétique, le développement de l'embryon et d'autres technologies naturelles sont là qui les attendent. L'accès à de tels stocks d'informations, la maîtrise de leur mystère les conduiront à des changements bien au-delà de ce qu'ils peuvent imaginer aujourd'hui.

Sex and reproduction

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Reproduction is the increase in number of cells or organisms, + whether unicellular or multicellular. Growth is increase in + size. All species of organisms grow and reproduce, although the + details of how they do it vary. Even though fusion of parental + gametes accompanies reproduction in humans and in the animals we + best know, biologically, sex is entirely distinguishable from + reproduction. Sex is defined as the formation of an organism + whose genes come from more than a single individual. Sex, the + recombining of genes from two or more individuals, does occur in + prokaryotes, but prokaryotic sex is not directly required for + reproduction.

Prokaryotic cells do not open their membranes and fuse their + contents. Rather, genes from the fluid medium, from other + prokaryotes, from viruses, or from elsewhere unidirectionally + enter prokaryotic cells. A prokaryote that carries some of its + original genes and some new genes is called a recom- + binant. This propensity for gene uptake, along with the lack of + a nucleus and the other features listed in Table I-2, defines + one of the two highest taxa, or superkingdoms: Prokarya, + organisms composed of bacterial cells. All other organisms are + Eukarya, organisms composed of nucleated cells, that evolved by + symbiogenesis (Table I-2).

Eukaryotic cells reproduce by mitosis. They form + chromosomes—tightly coiled gene packages bound together by + proteins and attached to the inner membrane of the nucleus. At + least two chromosomes are located in the nucleus of every + eukaryotic cell; some protoctists have more than 16,000 + chromosomes in a single nucleus at certain stages. Although all + cells and species of organisms made of cells must either + reproduce or die, the way that eukaryotes make more eukaryotic + cells or organisms made of cells is highly peculiar to each of + the eukaryotic kingdoms and forms the basis of our + classification system.

Lynn MARGULIS

Symbiogenesis

Natural Theology

Sexualité et commerce génétique planétaire

Sex and reproduction