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In 2007 two researchers, chemist Martin Hanczyc and artificial life scientist Takashi Ikegami, who were collaborating across disciplines agreed to test a hypothesis about the earliest forms of life (Hanczyc et al. 2007). They hypothesized that life’s precursors would need to move around their environment to take…
The metaphor of the computer represents in some crude fashion the chemistry of life. Nowadays one may assume that the average citizen of an industrialized country is at least as familiar with computers as with rain forests. The idea of using the computer as a metaphor is a natural one. A computer is a device for…
A hundred years ago, Charles Darwin could write books discussing the central problems of biology in language which was scientifically precise and still accessible to the general public. In those days the subject matter of biology was plants and animals. The language of Darwin was intelligible to experts and…
Every vitamin is made by living cells — either our own, or in other species. Vitamin D is produced in our skin, for example, when sunlight strikes a precursor of cholesterol. A lemon tree makes vitamin C out of glucose. Making a vitamin is often an enormously baroque process. In some species, it takes 22 different…
This IPCC finding makes several different assertions, each of which is worth considering in turn. First, it claims that atmospheric concentrations of greenhouse gases like CO2 are increasing, and as a result of human activity. This is a matter of simple observation. Many industrial processes, particularly the use of…
The chemists who uphold dualism are far from being agreed among themselves; nevertheless, all of them in maintaining their opinion, rely upon the phenomena of chemical reactions. For a long time the uncertainty of this method has been pointed out: it has been shown repeatedly, that the atoms put into movement during a…
Every breath you draw, every accelerated beat of your heart in the emotional periods of your oratory depend upon highly elaborated physical and chemical reactions and mechanisms which nature has been building up through a million centuries. If one of these mechanisms, which you owe entirely to your animal ancestry…
In the short run, knowing the gravitational constant to one more decimal digit of precision or placing even tighter limits on any deviation from Einstein's gravitational theory may seem like painfully nitpicking detail. Yet one must not lose sight of the "big picture." When researchers were measuring the properties of…
I would like to start by emphasizing the importance of surfaces. It is at a surface where many of our most interesting and useful phenomena occur. We live for example on the surface of a planet. It is at a surface where the catalysis of chemical reactions occur. It is essentially at a surface of a plant that sunlight…
... every chemical combination is wholly and solely dependent on two opposing forces, positive and negative electricity, and every chemical compound must be composed of two parts combined by the agency of their electrochemical reaction, since there is no third force. Hence it follows that every compound body, whatever…
In a sense, genetics grew up as an orphan. In the beginning botanists and zoologists were often indifferent and sometimes hostile toward it. 'Genetics deals only with superficial characters', it was often said. Biochemists likewise paid it little heed in its early days. They, especially medical biochemists, knew of…
While conceding that human behavior is indeed determined by the laws of nature, it also seems reasonable to conclude that the outcome is determined in such a complicated way and with so many variables as to make it impossible in practice to predict. For that one would need a knowledge of the initial state of each of…
No law of physics is more basic than the law of entropy, the tendency of the universe to move toward disorder and death. But life bucks the tide. using available free energy wherever it can get it, and hereabouts the most abundant source of energy is sunlight. The mayflower constructs its tiny oasis of order by…
When the first single-celled organisms appeared on Earth, more than 3 billion years ago, they fed upon carbohydrates—sugars—dissolved in the sea. The sugars had their origin in chance chemical reactions. Life, however, multiplied exponentially; one cell made two, two made four, four made eight, and so on. Self…