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Author Topic: A-Z Of Anything Or Anyone Associated With SCIENCE !!  (Read 346532 times)

Offline neilep

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Glycine  is the organic compound with the formula NH2CH2COOH. It is the smallest of the 20 amino acids commonly found in proteins, coded by codons GGU, GGC, GGA and GGG. Because it has specialized structural properties in protein architecture, this compact amino acid is often evolutionarily conserved. For example, cytochrome c, myoglobin, and hemoglobin all contain conserved glycines. Glycine is unique among the proteinogenic amino acids in that is not chiral. Most proteins contain only small quantities of glycine. A notable exception is collagen, which contains about 35% glycine. In its solid, i.e., crystallized, form, glycine is a free-flowing, sweet-tasting crystalline material.





Ewe can't look me in the eye and say that you are not fascinated by that can ewe ?
 

Offline Karen W.

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Why yes yes I can!!! LOL

HEAD.... THE UPPER TOP OF THE HUMAN BODY,
OPPOSITE OF THE FEET. THE HEAD HOLDS THE BRAIN AND CONSISTS HOUSES THE EYES, EARS, NOSE, MOUTH, TONGUE and MULTIPLE MUSCLES, BONES,BLOOD, TEETH ETC..ETC...ETC..
« Last Edit: 17/12/2009 08:03:58 by Karen W. »
 

Offline Don_1

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Why yes yes I can!!! LOL

HEAD.... THE HEAD HOLDS THE BRAIN

I might dispute that statement in some cases!!!

e.g. Traffic Wardens, it is a requirement by ALL local authorities here in the UK that Traffic Wardens should have hollow heads.
 

Offline neilep

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Indian summer is a name given to a period of sunny, warm weather in autumn, not long before winter. Usually occurring after the first frost, Indian summer can be in September, October, or early November in the northern hemisphere, and March, April, or early May in the Southern hemisphere. It can persist for a few days or extend to a week or more. This term is not related to the summer season in India.


A typical day within a period of "Indian Summer"

WIKI LINK HERE
 

Offline Karen W.

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Nice SAVE.... LOL...


Jewel BOX (Open Stellar Cluster)





NGC 4755: A Jewel Box of Stars
Credit & Copyright: Michael Bessell (RSAA, ANU), MSO

Explanation: The great variety of star colors in this open cluster underlies its name: The Jewel Box. One of the bright central stars is a red supergiant, in contrast to the many blue stars that surround it. The cluster, also known as Kappa Crucis contains just over 100 stars, and is about 10 million years old. Open clusters are younger, contain few stars, and contain a much higher fraction of blue stars than do globular clusters. This Jewel Box lies about 7500 light-years away, so the light that we see today was emitted from the cluster before even the Great Pyramids in Egypt were built. The Jewel Box, pictured above, spans about 20 light-years, and can be seen with binoculars towards the southern constellation of Crux.
 

Offline neilep

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Emil Theodor Kocher (August 25, 1841 – July 27, 1917) was a Swiss physician, medical researcher, and Nobel laureate for his work in the physiology, pathology and surgery of the thyroid.

Kocher was born in Berne, Switzerland. He studied in Zürich, Berlin, London and Vienna, and obtained his doctorate in Berne in 1865. In 1872, he succeeded Georg Albert Lücke as Ordinary Professor of Surgery and Director of the University Surgical Clinic at the Inselspital in Berne. He published works on a number of subjects other than the thyroid gland including hemostasis, antiseptic treatments, surgical infectious diseases, on gunshot wounds, acute osteomyelitis, the theory of strangulated hernia, and abdominal surgery. His new ideas on the thyroid gland were initially controversial but his successful treatment of goiter with a steadily decreasing mortality rate soon won him recognition. The prize money, from the Nobel prize he received, helped him to establish the Kocher Institute in Berne.

A number of instruments and surgical techniques (for example, the Kocher manoeuvre) are named after him, as well as the Kocher-Debre-Semelaigne syndrome.


 

Offline Karen W.

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lepton era

(′lep′tän ′ir·ə)

(astronomy) The period in the early universe, following the hadron era, during which electrons, positrons, neutrinos, and photons were present in nearly equal numbers; roughly between 10-4 and 20 seconds after the big bang.
 

Offline Karen W.

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MICROSCOPE!




 Microscope
Robert Hooke's microscope
Uses    Small sample observation
Notable experiments
   Discovery of cells
Inventor    Hans Lippershey
Hans Janssen
Related items    Electron microscope

A microscope (from the Greek: μικρός, mikrós, "small" and σκοπεῖν, skopeîn, "to look" or "see") is an instrument for viewing objects that are too small to be seen by the naked or unaided eye. The science of investigating small objects using such an instrument is called microscopy. The term microscopic means minute or very small, not visible with the eye unless aided by a microscope.

History

    See also: History of optics

Microscopes trace their history back almost 1200 years with Abbas Ibn Firnas's corrective lenses,[1] and it was Ibn al-Haytham's Book of Optics — written between 1011 and 1021 — that laid the foundation for optical research on the magnifying glass. Also, a device called the reading stone by an unknown inventor (thought to be Ibn Firnas) magnified text when laid on top of reading materials.[2]

The first true microscope was made around 1595 in Middelburg, Holland.[3] Three different eyeglass makers have been given credit for the invention: Hans Lippershey (who also developed the first real telescope); Hans Janssen; and his son, Zacharias. The coining of the name "microscope" has been credited to Giovanni Faber, who gave that name to Galileo Galilei's compound microscope in 1625.[4] (Galileo had called it the "occhiolino" or "little eye".)

The most common type of microscope—and the first to be invented—is the optical microscope. This is an optical instrument containing one or more lenses that produce an enlarged image of an object placed in the focal plane of the lens(es). There are, however, many other microscope designs.

[edit] Types
Several types of microscopes

"Microscopes" can largely be separated into three classes: optical theory microscopes (Light microscope), electron microscopes (e.g.,TEM), and scanning probe microscopes (SPM).

Optical theory microscopes are microscopes which function through the optical theory of lenses in order to magnify the image generated by the passage of a wave through the sample. The waves used are either electromagnetic (in optical microscopes) or electron beams (in electron microscopes). The types are the Compound Light, Stereo, and the electron microscope.

[edit] Optical microscopes

    Main article: Optical microscope

Optical microscopes, through their use of visible wavelengths of light, are the simplest and hence most widely used type of microscope.

Optical microscopes typically use refractive lenses of glass and occasionally of plastic or quartz, to focus light into the eye or another light detector. Mirror-based optical microscopes operate in the same manner. Typical magnification of a light microscope, assuming visible range light, is up to 1500x with a theoretical resolution limit of around 0.2 micrometres or 200 nanometers. Specialized techniques (e.g., scanning confocal microscopy) may exceed this magnification but the resolution is diffraction limited. Using shorter wavelengths of light, such as the ultraviolet, is one way to improve the spatial resolution of the microscope as are techniques such as Near-field scanning optical microscope.
A stereo microscope is often used for lower-power magnification on large subjects.

Various wavelengths of light, including those beyond the visible range, are sometimes used for special purposes. Ultraviolet light is used to enable the resolution of smaller features as well as to image samples that are transparent to the eye. Near infrared light is used to image circuitry embedded in bonded silicon devices as silicon is transparent in this region. Many wavelengths of light, ranging from the ultraviolet to the visible are used to excite fluorescence emission from objects for viewing by eye or with sensitive cameras.

    * phase contrast microscope:Phase contrast microscopy is an optical microscopy illumination technique in which small phase shifts in the light passing through a transparent specimen are converted into amplitude or contrast changes in the image.

A phase contrast microscope does not require staining to view the slide. This microscope made it possible to study the cell cycle.

[edit] Electron Microscope

Two major variants of electron microscopes exist:

    * Scanning electron microscope (SEM): looks at the surface of bulk objects by scanning the surface with a fine electron beam and measuring reflection. May also be used for spectroscopy.
    * Transmission electron microscope (TEM): passes electrons completely through the sample, analogous to basic optical microscopy. This requires careful sample preparation, since electrons are scattered so strongly by most materials.This is a scientific device that allows people to see objects that could normally not be seen by the naked or unaided eye.
    * Scanning Tunneling Microscope (STM): is a powerful technique for viewing surfaces at the atomic level.

The SEM, TEM, STM are include in the scanning probe microsocpy.

[edit] Established types of scanning probe microscopy

    * AFM, atomic force microscopy
          o Contact AFM
          o Non-contact AFM
          o Dynamic contact AFM
          o Tapping AFM
    * BEEM, ballistic electron emission microscopy
    * EFM, electrostatic force microscope
    * ESTM electrochemical scanning tunneling microscope
    * FMM, force modulation microscopy
    * KPFM, kelvin probe force microscopy
    * MFM, magnetic force microscopy
    * MRFM, magnetic resonance force microscopy
    * NSOM, near-field scanning optical microscopy (or SNOM, scanning near-field optical microscopy)
    * PFM, Piezo Force Microscopy
    * PSTM, photon scanning tunneling microscopy
    * PTMS, photothermal microspectroscopy/microscopy
    * SAP, scanning atom probe [5]
    * SECM, scanning electrochemical microscopy
    * SCM, scanning capacitance microscopy
    * SGM, scanning gate microscopy
    * SICM, scanning ion-conductance microscopy
    * SPSM spin polarized scanning tunneling microscopy
    * SThM, scanning thermal microscopy[2]
    * STM, scanning tunneling microscopy
    * SVM, scanning voltage microscopy
    * SHPM, scanning Hall probe microscopy

Of these techniques AFM and STM are the most commonly used followed by MFM and SNOM/NSOM.

[edit] Other microscopes

Scanning acoustic microscopes use sound waves to measure variations in acoustic impedance. Similar to Sonar in principle, they are used for such jobs as detecting defects in the subsurfaces of materials including those found in integrated circuits.




« Last Edit: 07/02/2009 01:13:40 by Karen W. »
 

Offline neilep

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Nanotechnology, which is sometimes shortened to "Nanotech", refers to a field whose theme is the control of matter on an atomic and molecular scale. Generally nanotechnology deals with structures of the size 100 nanometers or smaller, and involves developing materials or devices within that size.

Nanotechnology is extremely diverse, ranging from novel extensions of conventional device physics, to completely new approaches based upon molecular self-assembly, to developing new materials with dimensions on the nanoscale, even to speculation on whether we can directly control matter on the atomic scale.

There has been much debate on the future of implications of nanotechnology. Nanotechnology has the potential to create many new materials and devices with wide-ranging applications, such as in medicine, electronics, and energy production. On the other hand, nanotechnology raises many of the same issues as with any introduction of new technology, including concerns about the toxicity and environmental impact of nanomaterials , and their potential effects on global economics, as well as speculation about various doomsday scenarios. These concerns have led to a debate among advocacy groups and governments on whether special regulation of nanotechnology is warranted.
 

Offline Chemistry4me

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Offline neilep

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Otto Wallach
From Wikipedia, the free encyclopedia

Otto Wallach (27 March 1847 - 26 February 1931) was a German chemist and Nobel laureate for work on alicyclic compounds.




Wallach was born at Königsberg, the son of a Prussian official. His father was transferred to Stettin (Szczecin) and later to Potsdam. Otto Wallach went to school, a Gymnasium, in Potsdam, where he got in contact with literature and the history of art, two subjects he was interested his whole life. At this time he also started private chemical experiments at the house of his parents.

In 1867 he started studying chemistry at the University of Göttingen, where at this time Friedrich Wöhler was head of the organic chemistry. After one semester at the University of Berlin with August Wilhelm von Hofmann, Wallach received his Doctoral degree from the University of Göttingen in 1869, and worked as a Professor in the University of Bonn (1870-89) and the University of Göttingen (1889-1915). Wallach died at Göttingen.
 

Offline JimBob

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Π = Pi

The ratio of any circle's circumference to its diameter.

Binary Value           11.00100100001111110110…
Decimal Value            3.14159265358979323846…
Hexadecimal Value    3.243F6A8885A308D31319…

 

Offline Karen W.

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Quasar
Quasi-Stellar Radio Source


Taken from:

http://space.about.com/od/deepspace/a/quasarinfo.htm

"A Quasar is an enormously bright object at the edge of our universe with the appearance of a star when viewed through a telescope. It emits massive amounts of energy, more energy than 100 normal galaxies combined. The name comes from a shortening of quasi-stellar radio source (QSR). Current theories hold that quasars are one type of active galactic nuclei (AGN). Many astronomers believe supermassive black holes may lie at the center of these galaxies and power their explosive energy output. In one second, a typical quasar releases enough energy to satisfy the electrical energy needs of Earth for the next billion years."

"Hubble Image of Quasar
NASA, A. Martel, H. Ford, M. Clampin, G. Hartig, G. Illingworth, the ACS Science Team and ESA"



"It is thought by many astronomers that quasars are the most distant objects yet detected in the Universe. With the massive amounts of energy a quasar emits, it can be a trillion times brighter than our own sun. Because of this, they often drown out the light from all other stars in the same galaxy. Yet, despite this, they are not visible to the naked eye."

"Quasars were first detected in the 1960s as sources of radio waves. In addition to radio waves and visible light, quasars also emit ultraviolet rays, infrared waves, X-rays, and gamma-rays. Most quasars are larger than our solar system. A quasar is approximately 1 kiloparsec in width. Because of their distance, when we view quasars, we are seeing light from very early in the life of our universe, giving scientists information about the early stages of the Universe."
 

Offline Yomi

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Srinivasa Ramanujan was born in a poor Tamil Brahmin family that resided in the town of Kumbakonam. He attended school there and did averagely well. While in school he came across a book entitled A synopsis of elementary results in Pure and Applied Mathematics by George Carr. This book is just a compendium of results on integrals, infinite series and other mathematical entities found in analysis. Yet it left a lasting impression on Ramanujan; in fact it virtually determined his mathematical style. He would later write mathematics as a string of results without proof or with the barest outline of a proof.

     After school Ramanujan was hooked on mathematics. He spent all his time with his head over a slate working with problems in number theory that interested him and neglected everything else. The result was that he could never get through another examination. An early marriage as was usual at those times led to a frantic search for a job to earn an income. He became a clerk in the Madras Port Trust with the help of some well wishers.

     In the meantime Ramanujan kept showing his results to various people who he thought would be interested or would help him get a job that would give him a lot of time to do mathematics. He wrote to a couple of well known British mathematicians giving a list of some of the results he had obtained. They ignored him - thought he was a crank! Finally he wrote to one of the most distinguished English mathematicians of the time - a person who had done a lot of work on number theory - G H Hardy. Hardy arranged for Ramanujan to come to Trinity College, Cambridge where he and Ramanujan met almost daily discussing mathematics for about three years. Ramanujan died shortly after at the age of 33.

All interested people are referred to The Man Who Knew Infinity: A Life of the Genius Ramanujan by Robert Kanigel.


« Last Edit: 16/06/2009 09:05:34 by neilep »
 

Offline huafei

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Thanks for the info, I appreciate it.
 

Offline Karen W.

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Offline neilep

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Terby is a crater on the northern edge of Hellas Planitia, Mars. The 174 km diameter crater is centered at 28°S, 73°E with an elevation of −5 km. It is named after François J. Terby. It is the site of an ancient lakebed and has clay deposits.



 

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Offline neilep

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Venus




Second major planet from the Sun. Named for the Roman goddess, Venus is, after the Moon, the most brilliant natural object in the night sky. Venus comes closer to Earth—about 26 million mi (42 million km)—than any other planet. Its orbit around the Sun is nearly circular at a distance of about 67 million mi (108 million km) and takes 225 days; its rotation, in retrograde motion, takes even longer (243 days). As viewed from Earth, Venus undergoes phase changes similar to the Moon's, going through one cycle of phases in 584 days. It is seen only near sunrise or sunset and has long been known as both the morning star and the evening star. Venus is a near twin of Earth in size and mass but is completely enveloped by thick clouds of concentrated sulfuric acid droplets. Its surface gravity is about 90percnt that of Earth. Its atmosphere is over 96percnt carbon dioxide, with a pressure about 95 times Earth's. The dense atmosphere and thick cloud layers trap incoming solar energy so efficiently that Venus has the highest surface temperature of any of the Sun's planets, more than 860 °F (460 °C). Radar imaging indicates that the surface is dry and rocky, consisting mostly of gently rolling plains, broad depressions, and two large elevated regions analogous to continents on Earth; Venus also has impact craters, extensive lava fields, and massive shield volcanos. The interior is thought to be similar to that of Earth, with a metal core, a dense rocky mantle, and a less-dense rocky crust. Unlike Earth, Venus has no intrinsic magnetic field.
 

Offline neilep

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Yuty (A Mars Crater)






The crater is about 18 km in diameter, and is surrounded by complex ejecta lobes, one of which partly covers an older crater. Many craters at equatorial and mid-latitudes on Mars have this form of ejecta morphology, which is believed to arise when the impacting object melts ice in the subsurface. Liquid water in the ejected material would then allow it to flow, forming the characteristic lobe shapes.


Source:http://en.wikipedia.org/wiki/Yuty_Crater
 

Offline Karen W.

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http://www.google.com/search?q=volcano&ie=utf-8&oe=utf-8&aq=t&rls=com.ubuntu:en-US:unofficial&client=firefox-a

Aleutian Islands of Alaska, "Ash cloud"




Volcano
From Wikipedia, the free encyclopedia




Cleveland Volcano in the Aleutian Islands of Alaska photographed from the International Space Station, May 2006

Cross-section through a stratovolcano (vertical scale is exaggerated):
1. Large magma chamber
2. Bedrock
3. Conduit (pipe)
4. Base
5. Sill
6. Dike
7. Layers of ash emitted by the volcano
8. Flank    9. Layers of lava emitted by the volcano
10. Throat
11. Parasitic cone
12. Lava flow
13. Vent
14. Crater
15. Ash cloud
Pinatubo ash plume reaching a height of 19 km, 3 days before the climactic eruption of 15 June 1991

A volcano is an opening, or rupture, in a planet's surface or crust, which allows hot, molten rock, ash, and gases to escape from below the surface. Volcanic activity involving the extrusion of rock tends to form mountains or features like mountains over a period of time. The word volcano is derived from the name of Vulcano island off Sicily. In turn, it was named after Vulcan, the Roman god of fire.[1]

Volcanoes are generally found where tectonic plates are diverging or converging. A mid-oceanic ridge, for example the Mid-Atlantic Ridge, has examples of volcanoes caused by divergent tectonic plates pulling apart; the Pacific Ring of Fire has examples of volcanoes caused by convergent tectonic plates coming together. By contrast, volcanoes are usually not created where two tectonic plates slide past one another. Volcanoes can also form where there is stretching and thinning of the Earth's crust (called "non-hotspot intraplate volcanism"), such as in the African Rift Valley, the Wells Gray-Clearwater volcanic field and the Rio Grande Rift in North America and the European Rhine Graben with its Eifel volcanoes.

Volcanoes can be caused by mantle plumes. These so-called hotspots, for example at Hawaii, can occur far from plate boundaries. Hotspot volcanoes are also found elsewhere in the solar system, especially on rocky planets and moons.
 

Offline Karen W.

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Binary Star

http://en.wikipedia.org/wiki/Binary_star

From Wikipedia, the free encyclopedia
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For the band, see Binary Star (band).
This is a featured article. Click here for more information.
Hubble image of the Sirius binary system, in which Sirius B can be clearly distinguished (lower left).



A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star, comes,[1] or secondary. Research between the early 1800s and today suggests that many stars are part of either binary star systems or star systems with more than two stars, called multiple star systems. The term double star may be used synonymously with binary star, but more generally, a double star may be either a binary star or an optical double star which consists of two stars with no physical connection but which appear close together in the sky as seen from the Earth. A double star may be determined to be optical if its components have sufficiently different proper motions or radial velocities, or if parallax measurements reveal its two components to be at sufficiently different distances from the Earth. Most known double stars have not yet been determined to be either bound binary star systems or optical doubles.

Binary star systems are very important in astrophysics because calculations of their orbits allow the masses of their component stars to be directly determined, which in turn allows other stellar parameters, such as radius and density, to be indirectly estimated. This also determines an empirical mass-luminosity relationship (MLR) from which the masses of single stars can be estimated.

Binary stars are often detected optically, in which case they are called visual binaries. Many visual binaries have long orbital periods of several centuries or millennia and therefore have orbits which are uncertain or poorly known. They may also be detected by indirect techniques, such as spectroscopy (spectroscopic binaries) or astrometry (astrometric binaries). If a binary star happens to orbit in a plane along our line of sight, its components will mutually eclipse and transit each other; these pairs are called eclipsing binaries, or, as they are detected by their changes in brightness during eclipses and transits, photometric binaries.

If the orbits of components in binary star systems are close enough they can gravitationally distort their mutual outer stellar atmospheres. In some cases, these close binary systems can exchange mass, which may bring their evolution to stages that single stars cannot attain. Examples of binaries are Algol (an eclipsing binary), Sirius, and Cygnus X-1 (of which one member is probably a black hole). Binary stars are also common as the nuclei of many planetary nebulae, and are the progenitors of both novae and type Ia supernovae.
 

Offline Geezer

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D would have to be for Digital Systems. Is there any aspect of our lives that they have not altered in the last fifty years?
 

Offline neilep

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Extinction Event


An extinction event (also known as: mass extinction; extinction-level event, ELE) is a sharp decrease in the number of species in a relatively short period of time. Mass extinctions affect most major taxonomic groups present at the time — birds, mammals, reptiles, amphibians, fish, invertebrates and other simpler life forms. They may be caused by one or both of:

    * extinction of an unusually large number of species in a short period.
    * a sharp drop in the rate of speciation.

Over 97% of species that ever lived are now extinct, but extinction occurs at an uneven rate. Based on the fossil record, the background rate of extinctions on Earth is about two to five taxonomic families of marine invertebrates and vertebrates every million years. Marine fossils are mostly used to measure extinction rates because they are more plentiful and cover a longer time span than fossils of land organisms.

Since life began on Earth, several major mass extinctions have significantly exceeded the background extinction rate. The most recent, the Cretaceous–Tertiary extinction event, occurred 65 million years ago, and has attracted more attention than all others as it marks the extinction of nearly all dinosaur species, which were the dominant animal class of the period. In the past 540 million years there have been five major events when over 50% of animal species died. There probably were mass extinctions in the Archean and Proterozoic Eons, but before the Phanerozoic there were no animals with hard body parts to leave a significant fossil record.

Estimates of the number of major mass extinctions in the last 540 million years range from as few as five to more than twenty. These differences stem from the threshold chosen for describing an extinction event as "major", and the data chosen to measure past diversity.


Every time wifey cooks is almost an E.E !  ;D
 

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