Monday, December 28, 2015

Dark benediction

Walter M. Miller Jr.
Walter M. Miller Jr. was an American author of science fiction, known for a single book that has become a classic: A Canticle for Leibowitz, possibly one of the best science fiction novels of all time, at least among those in the apocalyptic sub-genre, which describes what might happen after a total nuclear war.
The novel is divided into three parts: In the first, Fiat Homo, the world is just beginning to recover from the disaster. As in the centuries following the fall of the Western Roman Empire, the Catholic Church takes the responsibility for saving what little remains of classical culture (ours) through the monks of an order founded by one man, Leibowitz, who before the nuclear conflagration was an electrical engineer. In the second part, Fiat Lux, several centuries have gone by, a new civilization has emerged and the world is entering a new Renaissance. In the third, Fiat Voluntas Tua, this civilization has reached its peak, materialism comes back, and history threatens to repeat itself. But this time Miller leaves a possible escape open: the colonization of the galaxy.

Thursday, December 17, 2015

The phenomenon of man

Pierre Teilhard de Chardin
We know from experience that man has a mind and consciousness. It is also evident that animals seem to have more mental activities the closer they are to us. Thus, mammals have more minds that reptiles, reptiles more than fish, fish more than invertebrates (possibly excluding cephalopods). All animals except sponges have a nervous system, although some have very little: the nematode Caenorhabditis elegans has only 300 neurons. Plants do not have a nervous system, but they have some sensitivity and are able to move slowly. And when Antonie van Leeuwenhoek discovered microorganisms in the seventeenth century, no one doubted that these tiny creatures were alive. True, biologists have not yet agreed on whether viruses, even more tiny beings, are alive or not. I have written about this in another post in this blog.

Thursday, December 10, 2015

How insect societies arose

Solitary bee (Megachile) and social bee (Apis)
Among the insect order Hymenoptera there are many species that live independently, but there are also many others who live together in societies. Social life has evolved several times, both among ants (all of which are social) and between bees and wasps, many of which live alone. This fact should be explained: why is social life so prevalent among these insects, and how could it have evolved? In other words, did it provide any evolutionary advantage? In which way?
In insect societies, most individuals renounce reproduction and dedicate their lives to care for the queen (the only member of the society who lays eggs) and for their brothers and sisters, while they are larvae. Normally there are at least two separate castes: those who are sexually active (male and female) and those who are not (usually asexual females). The differences between active and neutral females come from the type of food they receive during their larval stage.

Thursday, December 3, 2015

Malthus’s mistake

Thomas Robert Malthus
Since the end of the eighteenth century, apocalyptic warnings as regards the unstoppable increase of the world population have followed one another. In 1798, Thomas Robert Malthus published An essay on the principle of population, as it affects the future improvement of society, with remarks on the speculations of Mr. Godwin, M. Condorcet, and other writers. This essay includes the famous quotation:
Assuming then my postulata as granted, I say, that the power of population is indefinitely greater than the power in the earth to produce subsistence for man.
Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio. A slight acquaintance with numbers will shew the immensity of the first power in comparison of the second.