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Here, we intend to create a catalogue of prehistoric organisms! | Here, we intend to create a catalogue of prehistoric organisms! | ||
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| + | [http://web.archive.org/web/*sa_/http://www.palaeos.com/ Internet Archive] of Palaeos.com | ||
== Life == | == Life == | ||
| - | This section is the heart of Palaeos. We have to begin this section somewhere, and so this is also the Beginning of Life. If time permits, we will one day add sections on the definition of "life" and the ways it may have begun. However, that kind of systematic treatment is not exactly what this site is all about (see, infra, the Purpose of Life). So instead, we'll get right to business. | + | This section is the heart of Palaeos. We have to begin this section somewhere, and so this is also the Beginning of [[Life]]. If time permits, we will one day add sections on the definition of "life" and the ways it may have begun. However, that kind of systematic treatment is not exactly what this site is all about (see, infra, the Purpose of Life). So instead, we'll get right to business. |
=== Bacteria === | === Bacteria === | ||
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=== Chordates === | === Chordates === | ||
| - | == Time == | + | == [[Time]] == |
Geologists and Paleontologists measure the age of the Earth and the history of life in ages of millions and even billions of years. The entire history of humankind is but a blink of an eye next to the vastness of geological time. For this reason a special sort of "calendar" or "almanac" is required; one that measures not days, weeks, months or years, but millions and tens of millions of years. This is the Geological Time-Scale | Geologists and Paleontologists measure the age of the Earth and the history of life in ages of millions and even billions of years. The entire history of humankind is but a blink of an eye next to the vastness of geological time. For this reason a special sort of "calendar" or "almanac" is required; one that measures not days, weeks, months or years, but millions and tens of millions of years. This is the Geological Time-Scale | ||
| - | === Hadean === | + | === [[Hadean]] === |
The name Hadean was coined by geologist Preston Cloud for the pre-Isuan sequence whose record may not be preserved on Earth but is better known from Moon rocks. Consequently, the time sequence and stratigraphy of the Hadean are largely based on lunar events. For example the Nectarian Era is defined by reference to the formation of the Nectaris Basin (southwestern Nearside). The Hadean has no place in the ICS system followed in the rest of Palaeos. The ICS lumps everything earlier than 3600 Mya into the Eoarchean Era of the Archean Eon. | The name Hadean was coined by geologist Preston Cloud for the pre-Isuan sequence whose record may not be preserved on Earth but is better known from Moon rocks. Consequently, the time sequence and stratigraphy of the Hadean are largely based on lunar events. For example the Nectarian Era is defined by reference to the formation of the Nectaris Basin (southwestern Nearside). The Hadean has no place in the ICS system followed in the rest of Palaeos. The ICS lumps everything earlier than 3600 Mya into the Eoarchean Era of the Archean Eon. | ||
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=== Cenozoic === | === Cenozoic === | ||
| - | == | + | == Science and Literature == |
=== Evolution === | === Evolution === | ||
=== Geochronology === | === Geochronology === | ||
Current revision as of 20:29, 26 August 2006
Welcome to PaleosWiki!
Here, we intend to create a catalogue of prehistoric organisms!
Internet Archive of Palaeos.com
Contents |
Life
This section is the heart of Palaeos. We have to begin this section somewhere, and so this is also the Beginning of Life. If time permits, we will one day add sections on the definition of "life" and the ways it may have begun. However, that kind of systematic treatment is not exactly what this site is all about (see, infra, the Purpose of Life). So instead, we'll get right to business.
Bacteria
Bacterial phylogenetics and systematics are areas that are fraught with controversy, confusion and very little concordance. To attempt to fit some sort of analysis of them within the confines of a single web-page, and without years of study to give oneself authority, would be the height of folly. With that in mind, feel free to read on, as we strive to raise ourselves to greater heights than ever before. If any of the arguments presented seem somewhat circular and self-contradictory, they probably are. You have been warned.
Eukarya
Organisms in which the genetic material is contained within a nuclear membrane are known as Eukaryotes, the name means "true kernel". This domain includes all multicellular forms of life: Plants, Fungi, and Animals. However, in this section, we will deal only with the group classically called "Protista," single-celled Eukarya. In fact, the line is a bit vague. By convention, slime molds are treated as "protists" while sponges and Cnidaria (or at least most of them, as we will see) are treated as Metazoa. Similar uncertainty marks the borderlands of the plants and fungi.
Fungi
The Fungi are the great saprophytes, the master recyclers. They are the black rot, the dry rot, and the white rot, the colorful fate of last week's lasagna left too long in the 'fridge, and the great, grey walls of stinking mould that can destroy whole buildings. But, they are also the baker's yeast and the brewer's yeast. They are the difference between grape juice and Chateauneuf du Pape. They are the portobellos and the morels and the cloud ears and the truffles. In fact, the French could not be half so obnoxious about their cuisine were it not for the Fungi. But, then again, perhaps they could [1].
Plants
Beginning in the Archean era, Cyanobacteria evolved photosynthesis, which enabled them to use sunlight to draw carbon dioxide from the atmosphere and convert it to oxygen, water and glucose (a simple carbohydrate). These could be considered the first simple "plants" Plants therefore might be seen as any organism that is able to use sunlight, carbon dioxide, and water, to manufacture its own food, that is, as a special class of autotroph. However, that's far too broad. It would include all kinds of things like diatoms, chromists, and photosynthetic bacteria which have nothing to do with plants in a phylogenetic sense. They are, to be sure, all within the subject matter of a General Botany class. All of these groups share some essential biochemistry. However, what they don't share is a common ancestor to the exclusion of all other organisms. This similarity arises from (a) convergent evolution and (b) the exchange of plastids.
Invertebrates
Chordates
Time
Geologists and Paleontologists measure the age of the Earth and the history of life in ages of millions and even billions of years. The entire history of humankind is but a blink of an eye next to the vastness of geological time. For this reason a special sort of "calendar" or "almanac" is required; one that measures not days, weeks, months or years, but millions and tens of millions of years. This is the Geological Time-Scale
Hadean
The name Hadean was coined by geologist Preston Cloud for the pre-Isuan sequence whose record may not be preserved on Earth but is better known from Moon rocks. Consequently, the time sequence and stratigraphy of the Hadean are largely based on lunar events. For example the Nectarian Era is defined by reference to the formation of the Nectaris Basin (southwestern Nearside). The Hadean has no place in the ICS system followed in the rest of Palaeos. The ICS lumps everything earlier than 3600 Mya into the Eoarchean Era of the Archean Eon.
Archean
Rocks of the Lower Archean (in geology time is often referred to vertically, because younger rocks are deposited above older ones) are rare, and include the oldest known terrestrial rocks, from 3.8 to 4.2 billion years ago. Most of the oldest rocks are so altered through subsequent metamorphic processes it is difficult to know under what conditions they were formed. The situation is rather brighter with the more numerous rocks of the Younger ("Upper") Archean, from 3 to 2.5 or 2.6 billion years ago. These are mostly volcanic in nature, consisting of pillow-like structures identical to those of present-day lavas which have formed underwater. The implication is that at this time the entire Earth was covered by ocean. Perhaps the bulk of the continental masses, formed through volcanic outpourings, had yet to appear from beneath the waves.
Proterozoic
Beginning in the Archean era, Cyanobacteria evolved photosynthesis, which enabled them to use sunlight to draw carbon dioxide from the atmosphere and convert it to oxygen, water and glucose (a simple carbohydrate). These could be considered the first simple "plants" Plants therefore might be seen as any organism that is able to use sunlight, carbon dioxide, and water, to manufacture its own food, that is, as a special class of autotroph. However, that's far too broad. It would include all kinds of things like diatoms, chromists, and photosynthetic bacteria which have nothing to do with plants in a phylogenetic sense. They are, to be sure, all within the subject matter of a General Botany class. All of these groups share some essential biochemistry. However, what they don't share is a common ancestor to the exclusion of all other organisms. This similarity arises from (a) convergent evolution and (b) the exchange of plastids.
Paleozoic
The early Paleozoic saw the continents clustered around the equator, with Gondwanaland (representing the bulk of old Rodinia) slowly drifting south to the poles, and Siberia, Laurentia and Baltica converging in the tropics. There was a large ocean between Laurentia and Eastern Gondwanaland.
