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Ecology: biology of interaction. 2.14. (supplement) Some stages of the history of life on Earth
The oxygen revolution was the most significant turning point in Earth's history. Not only the composition of the atmosphere changed, but also the composition of rocks forming on Earth's surface. A consequence of an oxygenated atmosphere was the formation of the ozone layer in the atmosphere — a prerequisite for …
Hic sunt dracones
Discussion of the ideas and results of A. V. Kaminsky and S. E. Shnol, started here: /node/246
Ecology: The Biology of Interactions. 2.13. (Supplement) The Geochronological Scale
To describe the history of life on Earth, one needs a scale that allows the relevant spans of time to be described. How is this history studied? By the sequence of sedimentary rocks. The mutual sequence of the strata is determined by the character of their occurrence and by the …
Ecology: The Biology of Interactions. 2.12. (Supplement) The Origin of Life. Preliving Systems
For the origin of life, three conditions are necessary and sufficient. These are: the possibility of a full spectrum of transitional states between nonliving and living systems; the possibility of spontaneous transitions from one state to neighboring ones; and the action of selection, which preferentially preserves and reproduces the “more …
Ecology: The Biology of Interactions. 2.11. (Supplement) What Is Life?
Life is the maintenance and reproduction of characteristic highly ordered structures, a process that is improved in the course of evolution and carried out in accordance with an internal program by means of external sources of matter and energy.
Ecology: The Biology of Interactions. 2.10. (Supplement) The Evolution of the Universe, the Solar System, and the Earth
The age of the Earth, and of the Solar System, is 4.6 billion years. The Sun and planets formed from a gas-dust cloud produced by the destruction of preceding stars. Nuclear transformations in former stars are the reason for the diversity of chemical elements on Earth that makes life possible...
Ecology: The Biology of Interactions. 2.09. The Biogeochemical Cycle of Phosphorus
The BGC cycle of phosphorus is regulated much less effectively than the carbon and nitrogen cycles considered above, because phosphorus lacks an exchange pool in the atmosphere. Phosphorus is the principal element controlling the productivity of aquatic communities. The runoff of phosphates from fields into water bodies leads to their …
Ecology: the Biology of Interactions. 2.08. The Biogeochemical Cycle of Sulfur
Sulfur is a fairly abundant element in the Earth’s crust (fifteenth in chemical abundance), occurring in various oxidation states. It is an essential component of proteins. Sulfur is consumed (by autotrophs and most heterotrophic microorganisms) in oxidized form, as...
Ecology: the Biology of Interactions. 2.07. The Biogeochemical Cycle of Nitrogen
The BGC cycle of nitrogen is more complex than that of carbon. It is also extremely important for living organisms. Although the atmosphere contains more nitrogen than other elements, incorporating it into living matter is a much more difficult task than fixing carbon during photosynthesis. Nitrogen is most available to …
Ecology: the Biology of Interactions. 2.06. The Biogeochemical Cycle of Carbon
Naturally, discussion of the characteristics of the biogeochemical cycles of several key elements should begin with carbon. Carbon is the basis of organic compounds, and therefore the carbon cycle is of particular importance for living organisms. The most important feature of this cycle is the presence of carbon dioxide...
Ecology: the Biology of Interactions. 2.05. Energy Sources for BGC Cycles
The movement of elements in the biosphere is sustained by three main energy sources (“drive belts” for BGC cycles): solar energy transformed by the hydrosphere and atmosphere in the hydrological cycle; solar energy stored in organic substances during photosynthesis; and...
Ecology: biology of interaction. 2.04. Biogeochemical cycles
Terrestrial life is built on a highly complex chemical foundation. Its existence requires many chemical elements. Although the main compound in organisms is water, organic substances composed of diverse atoms are absolutely essential for life processes. From the elements, which...
Ecology: Biology of Interaction. 2.03. The Gaia Hypothesis (Metaphor)
In 1972, James Lovelock and Lynn Margulis proposed what became known as the «Gaia hypothesis» — the conception of Earth as a superorganism that maintains its own homeostasis. As Lovelock later noted, he and Margulis independently arrived at ideas previously expressed by James Hutton in...
Ecology: biology of interaction. 2.02. Noosphere
{ "title": "", "summary": "", "body": "Probably, the main author of the concept of \"noosphere\" was Pierre Teilhard de Chardin, a French priest and evolutionary scientist. Teilhard was a member of the Jesuit monastic order, and therefore the ideas he expressed publicly were limited by the discipline of the order. …
Ecology: the Biology of Interactions. 2.01. Biosphere
Chapter 2. Biospherology. The biosphere is the Earth’s shell transformed by the activity of living organisms. The alternative interpretation of the biosphere as the Earth’s shell within which living organisms occur, the “field of existence of life” according to V. I. Vernadsky, is much less useful...
Ecology: the Biology of Interactions. 1.14. (Supplement) Where Should We Seek the Causes of the Characteristics of Biosystems?
It is precisely the ecological-evolutionary approach to the study of biosystems that makes it possible to understand why they are as we observe them. The key to explaining the properties of any biosystem lies in considering the peculiarities of its relationships with the environment throughout its history.
Ecology: The Biology of Interaction. 1.12. (Supplement) Models: Their Limitations and Dangers
Some objects cannot be studied directly, or are extremely difficult to investigate in situ. In this and in many other cases, models are employed. A model is a system constructed for the purpose of studying an original system; it must exhibit a similar character of interaction among its parts and, …
Ecology: the Biology of Interactions. 1.13. (Supplement) Universal Properties of Biosystems
Despite all the specificity of biosystems of different levels, a number of universal properties can be distinguished for them. Let us name some of them: a definite composition and orderliness; hierarchical organization; metabolism; energy flow; capacity for development; adaptedness; self-regulation; dynamism; integrit...
Ecology: the Biology of Interactions. 1.08. Properties of Complex Systems
The more integrated a system is, the more difficult its mosaic description becomes. The brain is so complex because it is united by a multitude of connections (a neuron in the human brain may have 100 thousand synapses). It is possible that the human brain is the most complexly organized …
Illustration for a Conversation with A. V. Kaminsky
This is a fragment of a presentation from a lecture course devoted to the history of life on Earth. I have not yet begun posting that course, but these few slides will be useful for the conversation with A. V. Kaminsky taking place here. The fragment of the presentation given …