Kent Hovind complete calls from jail (1-4) Al Mazurek III 2026-09-21 | Kent Hovind complete calls from jail (1-4)
Epigenetics Neil Degrasse Tyson Al Mazurek III 2010-02-04 | Epigenetics is an emerging scientific field. Research focuses on the chemical changes that affect gene expression but do not alter the base sequence of DNA. These chemical changes include methylation, the addition of a methyl group to certain nitrogen bases. Researchers are studying these patterns of gene expression, which are passed on from parent to offspring. They are also studying how environmental factors can change the way in which genes are expressed. A growing body of evidence suggests that a wide variety of illnesses and behaviors may be linked to epigenetic mechanisms. These include various cancers, cognitive dysfunction, and autoimmune diseases. The environmental factors suspected of altering epigenetic processes include heavy metals, pesticides, tobacco smoke, and radioactivity.
Evolution and genetics in simple terms Al Mazurek III 2009-12-11 | Evolution and genetics once seemed worlds apart. While evolutionary biologists generally charted the paths that organisms had taken in the past, geneticists attempted to catalogue the present state of a species' genetic makeup, often with the aim of curing some human diseases in the future. By developing a system to analyze genetic information through an evolutionary lens, Harvard scientist Pardis Sabeti has helped to bridge the divide between these two scientific disciplines. Now she hopes that these new tools may one day help eliminate some of the world's deadliest diseases.Scientists have known for more than a century that evolution proceeds through a process of natural selection. Traits that are beneficial to an organism and improve that individual's chances of survival and reproduction are more likely to be passed on to future generations. Traits that are detrimental to survival are less likely to be passed on.
Dinosaur Mummy Found Al Mazurek III 2008-08-23 | A dinosaur mummy found in North Dakota reveals astonishing new information about the size of the reptiles, their skin, and how quickly they moved.
Synthesizing an Alkaloid - organic compounds Al Mazurek III 2008-07-23 | Synthesizing, or assembling, organic compounds can be a long and arduous process, involving numerous steps that add, change, or remove atoms from a framework. To synthesize an alkaloid, chemists must first know — or figure out — the composition and structure of the natural molecule to be replicated. Then, starting with very small structures that chemists already know how to make, they can begin to assemble these simpler molecules into fragments, called "intermediates," of the desired compound. This may involve lots of trial and error.
Booming Sands Al Mazurek III 2008-07-15 | Sand on a dune possesses energy in the form of gravitational potential energy. The greater the height of the sand dune, the more gravitational potential energy the sand on top has. When the sand on top of a steep dune is disturbed, it slides down the slope, and gravitational potential energy is transformed into kinetic energy. It is this kinetic energy of the falling sand that produces the booming sound. As the sand particles bounce against each other, some of their kinetic energy is transformed into acoustic energy -- or sound, waves of vibrations transmitted through a medium.
Transitional Tetrapod Fossil Al Mazurek III 2008-06-26 | Tiktaalik, from the Inuit word meaning "large shallow-water fish," had a flexible neck. This is significant because in modern tetrapods like amphibians, the head is separated from the body, whereas in fish it is not. Although Tiktaalik still had gills, it had lost the bony gill coverings that fish use to fan water and promote oxygen intake. This suggests that the "fishapod" may have been at least partly air-breathing, like modern tetrapods. Further, although Tiktaalik clearly had fins, the well-preserved bony, wrist-like arrangements near the tips of the fins suggested that the animal could push its body up off the ground, offering support much like a foot does. These fins, though still used for swimming, were clearly precursors to legs.
Big Bang Astronomy Theories Swift satellite Al Mazurek III 2008-02-22 | Swift is a satellite designed by Penn State researchers and launched by NASA to study gamma-ray bursts. Launched in November of 2005, the satellite was named after the swift, a small, quickly moving bird. Catching a GRB is no easy task. The burst can appear from any direction without warning and can last for only a few milliseconds to just over a minute. So, the satellite has to move quickly and be in position to capture the data. According to NASA, no other satellite turns faster. In addition to GRBs, Swift searches and records other phenomena it observes in the sky.
How Did Life Emerge Here? Evolution Al Mazurek III 2008-02-19 | If you were to explore the ground in almost any terrestrial region on Earth, chances are you would find soil. This layer of Earth's surface is essential to life. It supplies, both directly and indirectly, what we eat and wear, as well as the oxygen we breathe. Even so, it's easy to take soil for granted. You might assume that the soil near your home or elsewhere has been there forever. However, the land surface has changed dramatically over geologic time. For instance, depending on its location, soil formation may have been interrupted by volcanic activity, glacial movement, or climate change. In some parts of the world, entirely new land masses are forming as you read this. So what is soil, how does it form, and how does it support life?
The Grand Canyon: Evidence of Earths Past Al Mazurek III 2008-02-13 | Most of the Grand Canyon's exposed rocks belong to the third category: sedimentary rock. When mineral grains are eroded from surface materials, transported by water or wind, and eventually laid down on the ground or seafloor, a loose deposit of sediments forms. Over time, these soft sediments are compacted by mounting pressure and heat from subsequent overlying layers. Squeezed of their water, the sediment grains are cemented together, or lithified, to form solid -- though brittle -- rock.
The Grand Canyon: How It Formed Al Mazurek III 2008-02-09 | Erosive forces continue to shape the Grand Canyon today, millions of years after it began to form. Normal channel erosion alone, however, cannot explain the many kilometers that separate its rims. The strongest explanation holds that the major factor in the widening of the canyon has been activity from tributary drainage systems -- the side streams, rivulets, and gullies outside the main river channel. The greatest erosive force in these tributaries is the fast-moving landslide called a debris flow.
Ken Miller Human Chromosome 2 Genome Al Mazurek III 2007-11-28 | The phases through which chromosomes replicate, divide, shuffle, and recombine are imperfect, as DNA is subject to random mutations. Mutations do not always produce harmful outcomes. In fact, many mutations are thought to be neutral, and some even give rise to beneficial traits. To corroborate Darwin's theory, scientists would need to find a valid explanation for why a chromosome pair is missing in humans that is present in apes.
Hubble Telescope Deep space Al Mazurek III 2007-11-18 | From its low orbit just 600 km (373 mi) above Earth's surface, the Hubble Space Telescope is able to observe the universe with incredible clarity. Free from the atmosphere's turbulent air that blurs incoming light and absorbs infrared and ultraviolet wavelengths, Hubble has taken over 400,000 observations and provided data for thousands of scientific papers. Since its launch in 1990, Hubble — the only space telescope to gather data in visible, infrared, and ultraviolet wavelengths — has offered a unique and detailed view of the universe. One of the most striking images produced by the telescope was the Hubble Deep Field (HDF). At the time of its release in 1996, HDF was the deepest optical view of the universe, showing the farthest and youngest galaxies ever to be seen. The image was taken of a tiny portion of sky and displays over 1,500 galaxies with a wide range of shapes and sizes.
Neil Degrasse Tyson Evidence for the Big Bang Theory Al Mazurek III 2007-11-15 | The Big Bang theory states that approximately 14 billion years ago the universe burst into being from an unknown cosmic trigger. The early universe, contained within just a few millimeters, was very hot and densely packed with matter. Ever since that initial explosion, the universe has continued to expand and cool. Although generally accepted as the model for the origin and evolution of the universe, the Big Bang theory is not complete. For example, it does not explain what caused the initial expansion or why galaxies formed. However, there is significant evidence that the universe did originate from such an event. Three key pieces of observational evidence lend support to the Big Bang theory: the measured abundances of elements, the observed expansion of space, and the discovery of the cosmic microwave background (CMB).
Water Vapor Circulation on Earth Al Mazurek III 2007-11-12 | Water vapor -- the gaseous phase of water -- plays an important role in the water cycle and in regulating Earth's energy distribution. As oceans evaporate and plants transpire, liquid water from Earth's surface enters into the atmosphere as water vapor. When air cools, clouds form through water vapor condensation (forming liquid drops) or deposition (forming ice crystals); and clouds produce precipitation that returns liquid water back to Earth's surface. Water vapor is a critical component of Earth's atmosphere and, though it is invisible, it can be studied through the use of imaging that is sensitive to infrared wavelengths of about 6.5 to 7.4 micrometers in the electromagnetic spectrum. By assigning false colors to represent the infrared data, researchers are able to "see" water vapor in the atmosphere. In this simulation, water vapor is shown as white and precipitation is shown as orange.
Global Warming Arctic Climate Perspectives Al Mazurek III 2007-11-12 | In the past few decades, the annual average Arctic temperature has increased at almost twice the rate as that of the rest of the world. Evidence of this warming can be seen in the widespread melting of glaciers and sea ice, shortening of the snow season, rising sea level, melting of the permafrost, and other changes. This is causing reductions in some wildlife populations, unusual algae blooms, increased forest growth and more intense and frequent forest fires, unprecedented insect outbreaks, and more.
Evolution Desert Biome Al Mazurek III 2007-11-08 | The desert biome is characterized by low precipitation, a high rate of evaporation (seven to fifty times as much as precipitation), and a wide daily range in temperature. The dramatic temperature fluctuations are the result of low humidity, which allows up to 90 percent of solar radiation to penetrate the atmosphere and heat the ground during the day, then for this accumulated heat to be released back into the atmosphere at night. Precipitation in deserts, unlike other biomes, is highly irregular. In the Sonoran Desert, rain usually comes in short, sporadic clusters of rainy days three to fifteen times a year. On average, only one to six of these rainfalls is large enough to stimulate plant growth. Thus, Sonoran plants experience long periods of inactivity broken by periods of rapid growth and reproduction.
RNAi Discovered Al Mazurek III 2007-11-07 | oday, scientists are using the RNAi mechanism to learn more about what particular genes do and how to alter their function. Determining gene function is a relatively simple matter of inserting double-stranded RNA molecules that have a particular sequence into cells and observing the effects after RNAi silences the corresponding gene. Conceivably, this method may one day be used to silence gene mutations that cause human diseases such as Huntington's disease, rheumatoid arthritis, cancer, and many others. By using either the body's own mutations or viral invaders, scientists may develop a new type of drug—for example, one that switches off the genes of a cancer cell and leaves healthy cells unaffected. However, because RNAi's potential effects are so powerful, scientists must first determine that they can control the mechanism so that only the target gene is silenced, and not others.
Motion and Relativity Al Mazurek III 2007-10-22 | As seen in the first half of the video, according to Galilean relativity, speeds in different inertial frames of reference can be added to determine the relative speed of a moving object. For example, imagine you throw a ball forward at 10 mph while standing on a boat that is floating down a river at 5 mph (in the same direction that you throw the ball). In your frame of reference, the ball moves forward at 10 mph. However, from the point of view of an observer standing on the riverbank, the motion of the ball is described differently; to the observer, the ball moves forward at the speed of the throw plus the speed of the boat. Measured in the reference frame of the observer on the riverbank, the ball moves forward at 15 mph.
E=mc2 Time and Relativity special theory of relativity 2 Al Mazurek III 2007-10-22 | Einstein showed, mathematically, that space and time are related and perceived differently by different observers. One consequence of special relativity is time dilation, which means that time in a moving reference frame passes more slowly than time in a stationary reference frame. In other words, a clock that is moving with respect to a stationary observer is perceived by the observer to run more slowly than a stationary clock. Another consequence is length contraction—the observed decrease in length of objects traveling relative to an observer. As part of the special theory of relativity, Einstein also reconceived our understanding of momentum and energy. As the speed of an object approaches the speed of light, its inertia, or resistance to acceleration, also increases. In other words, its mass increases. Additionally, the theory yielded the famous equation E=mc2, which expresses the relationship between energy and mass.
Earth as a System// el nino, plate tectonics, human activity Al Mazurek III 2007-10-16 | The uneven heating also controls weather systems. The heat absorbed by the oceans and carried by its currents is constantly being released into the atmosphere. This heat and moisture drive atmospheric circulation and set weather patterns in motion. The weather patterns then influence vegetation, as well as erosion and sediment transport. Ever since the first photos were sent back from space, our view of Earth has changed. Remote sensing instruments, such as satellites, allow us to better understand the interrelationships between the different subsystems. For instance, recordings made by remote and Earth-based instruments show that significant surface warming has occurred over the past three decades. Knowing this, scientists are working to determine how this will affect — and already is affecting — the entire Earth system. astronomy
Light Years E=mc2 Al Mazurek III 2007-10-09 | Astronomers have more practical units of measurement, such as the light-year, to describe the vast distances between objects in the universe. Because light does not travel instantaneously—in a vacuum, light travels at a finite speed of about 300,000 km/s (186,000 mi/s)—it takes time for light to travel through the universe. One light-year is equal to the distance that light can travel in one year's time, which is nearly 10 trillion km. Thus, Proxima Centauri is about four light-years away. That means that it takes four years for the light emitted from Proxima Centauri to reach Earth. Andromeda is about two million light-years away—meaning it takes two million years for its light to reach Earth.
Einsteins Thoughts on the Ether theory of relativity Al Mazurek III 2007-10-09 | Albert Einstein used the Michelson-Morley results in his special theory of relativity, published in 1905. Einstein argued that light travels at a speed of 186,000 miles per second in all directions at all times and for all observers -- even if one observer is moving relative to another observer. That the speed of light does not vary defied the fundamental laws of physics passed down from Galileo and Newton. This and other assertions in the special theory of relativity completely changed the way scientists thought of time and space.
Intelligent Design? Blood Vessels Help Tumors Grow angiogene Al Mazurek III 2007-09-29 | Intelligent Design? A scientist begins by asking a question that can be answered by gathering evidence. Questions arise in all sorts of ways: for example, from observations, unexpected results, or the research findings of others. The scientist then develops an initial hypothesis, or possible answer to the question, arrived at based on past research or experience. In exploring the complex biology that enables cancerous tumors to grow, Dr. Judah Folkman formed his initial hypothesis based on decades of research. He suggested that tumors themselves can induce the formation of blood vessels, which in turn nourish the tumors. This phenomenon is called angiogenesis.
Swift: Gamma-Ray Bursts Al Mazurek III 2007-09-21 | Gamma rays are found at one end of the electromagnetic spectrum, which also includes radio waves, infrared light, visible light, ultraviolet light, and x-rays. Gamma-rays have a shorter wavelength and more energy than any other form of electromagnetic radiation. In the late 1960s, enormous bursts of energy in the form of gamma-rays were detected in space. Distributed randomly across the sky, these intensely energetic flashes stumped researchers. What astronomical phenomenon could create such powerful bursts of energy? Not only were the origins of the energy unknown, researchers could not even pinpoint whether the bursts were located within the galaxy or at cosmological distances.
Quarks: Inside the Atom Al Mazurek III 2007-09-21 | Matter is all the stuff that we see, feel, and smell around us. By definition, matter has mass and takes up space. Matter includes substances such as water, wood, rock, metal, plastic, and air, as well as countless other materials. All types of matter are made up of tiny particles called atoms. Atoms and the sub-atomic particles they're made of are far too small to be seen, even with the most powerful microscope. Despite this, physicists have developed an understanding of the structure of these particles through experimentation and indirect observation.
Evolution Genetics Embryos and our Common Ancestors Al Mazurek III 2007-08-28 | Even before Darwin, biologists recognized that species that looked quite different as adults often had close similarities as developing embryos. Many four -- legged animals go through embryonic stages that have similar features -- gill arches, a notochord, segmentation, and paddle-like limb buds -- as they develop into different adults. To Darwin, the embryonic resemblances were strong support for the theory of evolution. One of Darwin's contemporaries, German biologist Ernst Haeckel, summed up the argument in a famous, pithy statement: "Ontogeny recapitulates phylogeny." That is to say, in the process of development, an individual passes through the adult forms of all its ancestors. So, Haeckel proposed, by examining the development of an embryo you could read its entire evolutionary history in the transition from one stage to another. In fact, this isn't strictly true, and the drawings Haeckel made exaggerated the embryonic similarities between species.
Radiometric Dating age of the earth Al Mazurek III 2007-08-22 | http://www.myspace.com/acorvettes In the early decades of the twentieth century, scientists first developed an understanding that certain elements are radioactive and that these unstable isotopes decayed -- or lost particles from their nuclei, thus becoming different elements -- at a constant rate over time. Knowing a radioactive isotope's decay rate, a scientist can say that after a given amount of time, half of the atoms in a radioactive "parent" sample will be transformed into its stable "daughter" product. After another equal amount of time, half of the remaining radioactive atoms will decay. And so on. This is what is meant by "half-life." The half-life of uranium-238, the most abundant isotope of a radioactive element commonly found in the earth's crust, is 4.5 billion years.
Newtons Third Law of Motion: Astronauts in Outer Space Al Mazurek III 2007-08-17 | http://www.myspace.com/acorvettes NASA scientists and engineers should probably have predicted that if an astronaut applied force to open or close a valve, the valve would apply the same amount of force to him, but in the opposite direction. After all, nearly 300 years ago, Isaac Newton presented what came to be known as his third law of motion, which says that for every action there is an equal and opposite reaction. We experience these conditions on Earth; if we lean heavily against a wall, the wall pushes back with a force equal and opposite to our lean. (To illustrate the wall's opposing force more vividly, imagine leaning against it while wearing roller skates.) On Earth, gravity and friction provide the stability we need to resist the forces exerted on us during everyday tasks. In contrast, orbiting astronauts must struggle against conditions of "weightlessness."
Neil Degrasse Tyson The Elements: Forged in Stars Al Mazurek III 2007-08-15 | http://www.myspace.com/acorvettes All stars live by fusing hydrogen into helium. In the first step of the process, two hydrogen atoms fuse to form deuterium. In the next step, another hydrogen atom fuses with the deuterium, creating a rare isotope of helium that has two protons and one neutron in its nucleus. In the third step, two of the rare helium atoms fuse to create a single normal helium atom and two hydrogen atoms. The fusion pathway described above requires six hydrogen atoms to create one helium atom -- however, there are two hydrogen atoms left over at the end of the process. The net result is that it takes four hydrogen atoms to make one helium atom. The energy that fuels a star is a result of the difference in mass between the original four hydrogen atoms and the resulting helium atom. Following Einstein's mass-energy relationship, E=mc2, the missing mass is converted to energy
Evolution Dumb Americans 3 Al Mazurek III 2007-08-14 | http://www.myspace.com/acorvettes The less educated you have, the less you understand evolution or for that matter science. The only reason given for not understanding evolution was that it conflicted with religious beliefs and not looking at all the evidence. WOW that's a good reason LOL
Einstein Gravity and the Expanding Universe Al Mazurek III 2007-08-13 | http://www.myspace.com/acorvettes Scientific understanding is always subject to change. Not long after Einstein proposed the cosmological constant, scientists observed that the universe was much bigger than previously thought; the astronomer Edwin Hubble concluded it was, in fact, expanding. Faced with this knowledge, Einstein renounced his own idea, calling it his "biggest blunder." Though Hubble's new findings were widely accepted, scientists now faced new questions: If the universe was so big and continuously expanding, what was driving expansion? And shouldn't the force of gravity at least be slowing it down?
Evolution BT Corn Genes and Bug Genes Al Mazurek III 2007-08-09 | http://www.myspace.com/acorvettes Splice the genes for a naturally pest-killing microbe into a crop plant so that the corn or wheat or potato plants themselves become lethal to the pests. No more wasteful -- and expensive -- spraying of toxic pesticides. Instead, the bugs taste the leaves and go off to die. Indisputably, it works. The genes of Bacillus thuringiensis, or Bt, have been added to corn, cotton, potatoes, and other crops, with the desired results. Scientists are aware, however, that any effort to manipulate the ecological balance must reckon with the evolutionary consequences. So even before the first Bt crops were planted, scientists, farmers, and regulators began worrying about unintended effects.
Evolution Toxic Newts Al Mazurek III 2007-08-07 | http://www.myspace.com/acorvettes One well-documented example of an arms race adaptation is the potent poison in the skin of the newt Taricha granulosa, which is food for the garter snake. Over time, some genetic variants of the snake that are resistant to the toxin have emerged -- and variants of the newt have become more poisonous. Yet another example is a species of snake that feeds on slugs. Some of the slugs have evolved a stickiness that makes them hard for the snake to swallow. There are, of course, structural and ecological limitations on just how much escalation can occur.
Coral Reef Ecosystem Al Mazurek III 2007-08-06 | http://www.myspace.com/acorvettes All living things require energy to carry out life functions such as growth, movement, and reproduction. For nearly all ecosystems—diverse collections of species that interact with each other and their physical environment—the major source of energy is the sun. The flow of energy tends to follow the same basic pattern whether the ecosystem is a tropical rainforest or a coral reef. To portray the transfer of energy through an ecosystem, ecologists use simple models called food chains. Organisms can be organized into different trophic levels, or positions in a food chain; organisms at higher trophic levels feed on those at lower levels.
Quantum Mechanics Al Mazurek III 2007-08-04 | http://www.myspace.com/acorvettes The Danish physicist Niels Bohr, who worked in Rutherford's lab, was the first to describe orbits of fixed size and energy in which electrons are free to travel without losing energy and falling toward the nucleus. According to this model, published in 1913, electrons can only occupy or jump between fixed energy levels and cannot reside in between these levels. In addition, once in their "ground state," electrons maintain the energy they contain. This energy keeps them in perpetual motion, allowing them to resist the attractive force of the nucleus.
Quantum Mechanics The Uncertainty Principle Light Particles Al Mazurek III 2007-08-04 | http://www.myspace.com/acorvettes Single photons are the smallest quantities of light and, despite having no mass, have many properties in common with particles. In fact, physicists often think of photons as particles -- particles that sometimes behave like waves. Physicists sometimes describe all particles as waves -- even those with mass, such as electrons and protons -- in order to better understand certain aspects of their behavior.
Galileo Sun-Centered System Al Mazurek III 2007-08-03 | http://www.myspace.com/acorvettes When Galileo published his book debating the Copernican and Ptolemaic systems, the Church found him guilty of heresy and sentenced him to house arrest for the rest of his life. Today, Galileo is recognized for his revolutionary work in both astronomy and physics, and has been referred to as "the father of modern science." In addition to his findings in support of the Copernican system, his theories regarding falling objects and objects in motion laid the groundwork for classical mechanics. He was also a pioneer in the approach we call the scientific method, which utilizes observation and experiment. In 1992, three hundred and fifty years after his death, the Church officially apologized for condemning Galileo and his scientific research.
Hubbles Expanding Universe Red Shifts The Big Bang Al Mazurek III 2007-08-02 | http://www.myspace.com/acorvettes Before 1919, most scientists held that the universe was only as large as the Milky Way and that it was a constant size. Then, in 1919, the American astronomer Edwin Hubble — aided by a technologically advanced 100-inch telescope — was able to discern individual stars within what he believed to be a nebula, a fuzzy cloud of light composed of cosmic gases. After calculating that the distance to these stars from Earth was much further than the known reaches of the Milky Way, he concluded that the stars were part of a galaxy separate from our own. The idea that our galaxy was just one of many galaxies changed forever the way we view our place in the universe.
Natural Selection Tale of the Peacock Al Mazurek III 2007-08-01 | http://www.myspace.com/acorvettes Peahens often choose males for the quality of their trains -- the quantity, size, and distribution of the colorful eyespots. Experiments show that offspring of males with more eyespots are bigger at birth and better at surviving in the wild than offspring of birds with fewer eyespots. This way of choosing a mate is just one type of sexual selection: members of one sex mating in disproportionate numbers with members of the opposite sex that possess some "showy" feature. It might be ornate peacock plumage, large antlers on a deer, or a bird's particularly melodious mating call. Another type of sexual selection is combat among members of the same sex to choose an available mate.
Evolution Genetic Tool Kit Al Mazurek III 2007-07-31 | http://www.myspace.com/acorvettes The genes containing developmental instructions for the body plan are known as homeobox-containing genes. The DNA code in homeobox genes directs the cell to make chemical sequences, which in turn regulate still other genes that affect the positioning of cells in the embryo. While this sounds complicated, it is a far more elegant and simple mechanism than scientists thought could possibly be responsible for the enormous variation we see when we survey the animal kingdom.
Evolution The Common Genetic Code Al Mazurek III 2007-07-30 | http://www.myspace.com/acorvettes The often-mentioned fact that humans and chimpanzees are 99.9 percent identical in their DNA is hard to accept for some people, who can't comprehend how we could share so much of our basic genetic endowment even with the most humanlike ape. Yet this genetic similarity is very real, and it dramatically shows how parsimonious natural selection can be -- it reuses genes and structures that have worked well in the past.
Dating Lava Flows on Mauna Loa Volcano, Hawaiʻi Al Mazurek III 2007-07-27 | http://www.myspace.com/acorvettes Flowing lava erases nearly everything in its path. An entire forest can be wiped out by streams of molten rock. In some circumstances however, a flow may encase a small amount of plant material before it is entirely incinerated. Starved of the oxygen required for combustion, these bits of organic material are preserved inside the cooling lava. When geologists find these artifacts, they can use them to date the lava flows that contain them.
Stem Cells: Seeds of Hope? Al Mazurek III 2007-07-26 | http://www.myspace.com/acorvettes Despite enormous strides in medical technology in the last several decades, dozens of diseases and other medical conditions remain incurable. Severe spinal cord injuries cause lifelong paralysis because doctors have not yet found a way to repair delicate nerve tissue. Medical researchers have also been unable to find a cure for Tay-Sachs, even though they know the cause of this devastating disease, which claims the lives of most of its victims before they reach the age of six. The list goes on: Diseases like diabetes, multiple sclerosis, Alzheimer's, and Parkinson's remain incurable, despite tireless searches for cures.
Neil degrasse Tyson Ingredients for Life: Carbon Al Mazurek III 2007-07-26 | http://www.myspace.com/acorvettes Neil degrasse Tyson Ingredients for Life: Carbon
Neil degrasse Tyson Ingredients for Life: Water Al Mazurek III 2007-07-24 | http://www.myspace.com/acorvettes Since the 1970s, a number of unusual organisms have been discovered in environments that are hostile to other living things. These organisms, called extremophiles because of their ability to survive at the extremes of typically hospitable conditions, thrive where other life would perish. For example, microbial life has been found deep underground in tiny spaces within rocks, in the frozen environment of Antarctica, in the searing hot waters of deep sea vents and hot springs, and in the harsh environments of dry deserts. Life has also been found in extreme conditions of high radiation, pressure, acidity, alkalinity, or salinity. With the discovery of such organisms, some scientists have broadened their definition of what a habitable environment might be to include a greater range of potential environments for extraterrestrial life.
Evolution Permian-Triassic Extinction Al Mazurek III 2007-07-21 | http://www.myspace.com/acorvettes One of the most dramatic and mysterious events in the history of life, the so-called "Great Dying" of animals and plants some 250 million years ago, continues to fascinate and baffle scientists. Of the five or so mass extinctions recorded in Earth's fossils, this one at the end of the Permian period and the start of the Triassic was the most catastrophic. More than half of the families of living things died out, and as many as 90 to 96 percent of the planet's marine species were lost. At the same time, perhaps 70 percent of the land's reptile, amphibian, insect, and plants species went extinct.
Evolution Walking Tall Al Mazurek III 2007-07-18 | http://www.myspace.com/acorvettes The transition to upright walking that happened in the earliest stages of hominid evolution demanded a significant range of adaptations of the skeleton and muscles. But it was not quite as dramatic a transformation as it might at first appear. Almost all primates can sit upright, many can stand upright, and a few can even walk upright (although not for long, nor very efficiently). In other words, there has been a pattern in primate evolution of an upright body position -- whether clinging vertically to a tree trunk, leaping like a lemur, or swinging through the branches like an ape. The transition to bipedalism in hominids could build on this evolutionary pattern; it didn't require the direct transformation of a true quadruped like a horse into a committed biped.
Evolution Sweaty T-shirts and Human Mate Choice Al Mazurek III 2007-07-16 | http://www.myspace.com/acorvettes Maybe it's not similar interests, horoscope signs, looks, or proximity that make women and men fall in love. According to evolutionary scientists, when people throw up their hands and say "it was just chemistry," they may be on to a fundamental factor in mate choice. Subtle chemical signals, or pheromones, have long been known to draw pairs together within the same species, and for a specific reason. In mice, for example, experiments showed that pheromones acted as attractants between males and females who were genetically similar except that they differed in a certain type of immune system gene. That difference is actually a survival benefit: The combination of two individuals' different MHC (major histocompatibility locus) genes gives their offspring an advantage in beating back disease organisms. So the mice could smell a genetic difference. But could modern humans, who aren't known for a particularly good sense of smell, also make that distinction?
Evolution Laetoli Footprints Al Mazurek III 2007-07-15 | http://www.myspace.com/acorvettes Thank goodness for the irrepressible urge of humans (and other animals) to joke and play around in nearly any situation. Sometimes, it pays big dividends. It certainly did in 1976, when paleoanthropologist Andrew Hill and a colleague were tossing elephant dung at each other in Laetoli, a hominid archeological site in Tanzania. As Hill dived out of the way, he stumbled on what turned out to be one of the wonders of prehistoric finds: a trail of hominid footprints about 3.6 million years old. The majority of the Laetoli footprint site was excavated in 1978. Until then, the oldest known footprints of human ancestors were tens of thousands of years old. But this trail, some 80 feet long and preserved in cementlike volcanic ash, had been made by some of the first upright-walking hominids. An almost unimaginable sequence of events preserved what paleontologist Ian Tattersall calls a fossil of human behavior -- prehistoric walking.
Evolution Homo Sapiens Versus Neaderthals Al Mazurek III 2007-07-12 | http://www.myspace.com/acorvettes About 100,000 years ago, a diverse group of hominids, or humanlike species, occupied Earth. By 30,000 years ago, however, only Homo sapiens—the most modern species—remained. One of the most hotly debated issues in paleoanthropology, the study of human origins, focuses on how Homo sapiens evolved to outlive the other hominids. The current best explanation for the beginning of modern humans is the Out of Africa model. This holds that Homo sapiens arose in Africa and gradually replaced hominid species in the other parts of the world to which they migrated. To address the question of why our species survived, paleoanthropologists make certain assumptions about lifestyle and behavior based on fossil evidence.
