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 BobIn losing this simple, beautiful and obviously true philosophy, we lose everything. |
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Bob “How can you buy the sky? Chief Seattle began. How can you own the rain and the wind? My mother told me, Every part of this earth is sacred to our people. Every pine needle. Every sandy shore. Every mist in the dark woods. Every meadow and humming insect. All are holy in the memory of our people. “My father said to me, I know the sap that courses through the trees as I know the blood that flows in my veins. We are a part of the earth and the earth is a part of us. The perfumed flowers are our sisters. The bear, the dear, the great eagle, these are our brothers. The rocky crests, the meadows, the ponies — all belong to the same family. “The voice of my ancestors said to me, Every shining water that moves in the rivers and streams is not simply water, but the blood of your grandfather’s grandfather. Each ghostly reflection in the clear waters of the lakes tells of memories of the life of our people. The water’s murmur is the voice of your great-great-grandmother. The rivers are our brothers. They quench our thirst. They carry our canoes and feed our children. You must give to the rivers the kindness you would give to any brother. “The voice of my grandmother said to me, Teach your children what you have been taught. The earth is our mother. What befalls the earth befalls all the sons and daughters of the earth. “Hear my voice and the voice of my ancestors, Chief Seattle said. This we know: All things are connected like the blood that unites us. We did not weave the web of life, We are merely a strand in it. Whatever we do to the web, we do to ourselves. “We love this earth as a newborn loves its mother’s heartbeat. If we sell you our land, care for it as we have cared for it. Hold in your mind the memory of the land as it is when you receive it. Preserve the land and the air and the rivers for your children’s children and love it as we have loved it.” |
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cooperation, competition and evolution The evolution doesn't necessarily select the strongest individuals but also the most cooperative one. He cites plenty of species which survive because they cooperate : insects, fishes, mammal...) The swallow which to migrate on its own has little chance, the lonesome dolphin has more chances to be eaten by a shark, etc. Kropotkin concludes that a society based on cooperation rather than competition has good chances of success and therefore develops a libertarian socialist theory. |
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Clarification on 'anarchist' This is NOT the classical meaning. Originally, it means 'no Archos' or 'no ruler'. In the times when most 'rulers' were absolute monarchs, where being the 'ruler' meant being above the law, being the source of laws over others, and the power to act at whim. In that sense, classical 'anarchy' covers a wide field, from modern Libertarianism all the way across to Constitutional Democracy. Any system in which the 'Ruler' is subject to law himself, rather than being the sole source of law. |
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The Quandary. Albert Einstein |
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Evolution can be seen QED |
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Evolution is not a hypothesis. For over 150 years—since the time of Charles Darwin—the Theory of Evolution has been through more scrutiny and rigorous investigation than just about any other scientific claim. And the theory has only been strengthened as more evidence has been accrued. While there are many that people who, for ideological reasons, want to make it seem like evolution is not widely accepted within the scientific community, this is not actually the case. Across universities, research institutions, and scientific organizations, evolution is not only nearly universally accepted, it is also the basis upon which active, exciting, and important research is being done. Indeed, the scientific fact that is evolution is the basis of most of biology. To that end, this is a complete overview of the most direct evidence in support of evolution. Common Traits. Common Ancestor. Think about your family. You and your closest relatives look more alike than you and your cousins. Likewise, you look more like your cousins than you do more distant relatives, and more like distant relatives that people on the other side of the globe. The closer you are related, by-and-large, the more similarities you share. Of course, these similarities extend well beyond the surface level, reaching into our genetics. (Image source: Sinauer Associates, Inc.) This patterning, like in your family, extends throughout all life on Earth. The patterning of the similarities speaks volumes. In evolution, these “similarities” are known as “synapomorphies.” They are characteristics that are present in ancestral species and are shared exclusively (in more or less modified form) by this species evolutionary descendants. Synapomorphies come in nested hierarchies that are related to the variety and intensity of the similarities. Why is this the case? The similarities have been inherited from common ancestors, and the further back in time any two species shared a common ancestor, the more faded and distant the similarities become. It is important to note that, species with a large number of similarities tend to live near each other—penguin species only live in the Southern Hemisphere, marsupials live almost exclusively in Australia, cacti almost exclusively in the Americas, lemurs in Madagascar, etc. If evolution was not true, this geographic patterning would make absolutely no sense. Furthermore, these similarities often seem to be completely arbitrary, rather than having some selective advantage. Illustrative example: Insects, though unbelievably diverse, have 6 legs. There are likely several hundred thousand insect species and they all have pretty much the same body plan. (Image source: Wikimedia Commons) We See Species Changing Over Time One of the most important discoveries that lead to Darwin’s Theory of Evolution was extinct animals found as fossils. Early paleontologists, like Charles Lyell and George Cuvier, noticed a very simple fact: Species that lived in the past are very often drastically, wildly different from anything alive today. Trilobites, dinosaurs, giant sloths, baculites, etc., they all suggest that life on Earth has changed quite a bit. That would be interesting enough on its own. What makes it more interesting is that, the further back one goes, the more different the species appear when compared to today’s species. These overarching trends can also be seen on the individual level, as lineages can be seen changing over time. How do we know, though, that fossil progressions don’t just represent separate, unrelated species? First, they have similarities that suggest they are related (see above reasoning concerning similarities between species). Secondly, they represent a trend, also known as a progression of change. For instance, over time, the species go from low expression of a certain trait to intermediate expression to high expression. Like the evolution of legs, for example. In fact, since we are on the topic, there is no missing link in evolution. Lastly, the fossils are dated and organized by direct means (like radiometric dating) or indirect means (like relative dating using unique marker layers, fossils, or other techniques). Example fossils: (source) Human evolution. (source) Fossils aren’t the only way that we can see species changing. We can see it in a laboratory, across geographic distribution as a species spreads, or through artificial selection performed by humans. Examples of species changing in recorded history: All these common vegetables were once wild mustard. (source) The Remnants of Past Generations Turn over a manufactured product today, and you are likely to see a small sticker or tag that says what country it was made in. Like those tags, species bear the marks of where they came from. These signs of origin might come in the form of repurposed traits, traits that hurt a species chances of surviving or reproducing. Put simply, species are flawed, and it’s these flaws that clearly tell of their natural origin. Examples: If you didn’t know any better, you might think this was a flattened elephant foot. Well, that’s not far from the truth since manatees are closely related to elephants. The West Indian manatee (Trichechus manatus) has fingernails on its flippers and hair on its body (visible in this photo). (Image source: Fritz Geller-Grimm) Other non-human mammals can produce Vitamin C. They don’t need it from their diet. Humans, on the other hand, have had ancestors that have been eating fruit for so long (which is high in vitamin C) that our vitamin C genes long ago mutated. We do, however, still possess its remnant in pseudogene form. (source) What’s so powerful about learning these three basic facts about evolution is that you now have the ability to look at any species and ask yourself these questions: Does this species share similarities with other species that might suggest that they are closely related? Are there progressions of change for this species that we can see in the fossil record, recorded history, or across geography? Does this species have any traits that are the remnants of past generations? |
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hog Sorry for libertarian socialism : translation from the French. The term in English is : anarcho communism : en.wikipedia.org Bakunin and Marx more or less agreed on the final result they want to obtain (i.e. socialism) but Marx considered that a period of "dictate of the proletarians" was necessary : socialism mus be imposed from the top of the pyramid. Bakunin (and the other anarchists after him) considered that once you have established a dictate, you cannot get rid of it and that such a system would lead to a gigantic bureaucracy (seems almost prophetic now). He argued with Marx. The anarchists (at least the Libertarian Socialist branch) consider that the people must arrange within groups : neighbours, colleagues... and that those groups have to fix their own rules, by discussing (ex : some anarchists consider that each one should receive a loan corresponding to what he has produced, others that you receive a loan corresponding to your need). Then, the groups have to work with other groups to find compromises. That, if leaders are sometimes necessary, the group should be able to fire that so that no individual can seize the might - the vote is considered as evil, sometimes necessary but looking for a consensus is the best way to rule the groups. |
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Important fossil find 300 million-year-old fossil skeleton in Utah could be the first of its kind (CNN) — An approximately 300 million-year-old fossil skeleton discovered at Canyonlands National Park in Utah could be the first of its kind, researchers say. The exact species and classification have yet to be determined, but the fossil is a tetrapod -- meaning animal with four legs -- and could be an early ancestor of either reptiles or mammals. Paleontologists have determined the fossil could be anywhere from 295 million to 305 million years old, between the Pennsylvanian and the Permian geologic time periods. "It's a phenomenal specimen. You do not see something like that very often, so it's really significant for that in itself," said Adam Marsh, lead paleontologist at Petrified Forest National Park in Arizona. "But what it indicates is that there's probably more fossils out there, especially at Canyonlands, in this really important time interval." A team of scientists and paleontologists from Petrified Forest, the Natural History Museum of Utah and the University of Southern California helped collect the fossil from Canyonlands. The fossil was found as a complete skeleton, and the bones were in their "life positions," meaning the same position as when the animal was alive. This fossil appears to be an early amniote, which is a land-living vertebrate that lays eggs, according to Adam Huttenlocker, an outside specialist on the team who researches early tetrapod fossils and is an assistant professor at USC. The complete skeleton allows scientists to analyze the evolution of amniotes, in addition to the ancestors of early reptiles and mammals. This area of Canyonlands hasn't produced amniote fossils in the ancient rock formation the fossil was found in, so Huttenlocker said there's a good chance this fossil represents a new species of early amniote. The fossil excavation of a lifetime A park ranger at Canyonlands reported the fossil around October 2020. After the research permit was processed, the team collected the fossil a year later, on October 23 of this year. Matthew Van Scoyoc said this was the first time he's seen anyone apply for a research permit to extract a fossil in his four years as the research coordinator of the National Park Service's Southeast Utah Group, which includes Canyonlands. He coordinates research and provides permits for these parks, but excavating hasn't been a part of the job -- until now. "I never thought I'd get to go on a fossil excavation in my life, and that was just really, really cool," Van Scoyoc said. First ancient fossil of Homo naledi child found in the Cradle of Humankind The excavation took an entire day, Van Scoyoc said. The team hiked 13 miles roundtrip into the backcountry, extracted the fossil in two pieces and hiked back with a skeleton in their backpacks. (The fossil's original location, Lost Canyon, is designated as a wilderness area by the National Park Service, so no motorized vehicles were allowed.) The fossil is now at the Petrified Forest fossil preparation lab for tests and scans of the skeleton and skull. After scientists determine the species, which could take at least a year, Marsh said the fossil will remain with the National Park Service for further research and museum exhibits. There is a possibility that this fossil is a new species, which is rare -- Marsh said some paleontologists go their entire careers without a discovery of that kind. But even if the fossil turns out to be a known species, Marsh said this finding is still significant for understanding the biodiversity of that time. Fossil specimens from aquatic animals like shark spines are common finds at Canyonlands, especially along the river, but Huttenlocker said this is the first time he has been notified of a land-living vertebrate fossil. "This is a rare, once-in-a-lifetime opportunity for me," Huttenlocker said. 'Scraping the surface' The fossil was at risk for erosion from rain and water, which is why Van Scoyoc said they issued the permit. Canyonlands does not have any paleontologists on staff, so they outsourced paleontologists from Petrified Forest, which is known for its fossils. "Fossils themselves are probably not that rare in Canyonlands. It's just, we haven't looked for them thoroughly," Van Scoyoc said. "What's happening now is we, as the National Park Service, are able to consider them more." The ancient skeleton researchers collected at Canyonlands National Park was from an amniote, or land-living vertebrate that lays eggs. The ancient skeleton researchers collected at Canyonlands National Park was from an amniote, or land-living vertebrate that lays eggs. National park sites are full of undiscovered fossils, Marsh said. The collaboration between park staff and researchers from different parks and institutions is integral, he said, to their discovery. "We're just now scraping the surface about nuts-and-bolts paleontology," Marsh said. You can channel your inner paleontologist next time you're at a national park. Marsh said if you think you see a fossil -- don't try excavating it yourself -- send a picture and location to park staff. "This is exactly how we find things that we don't know about otherwise, because we're not always able to get out to certain areas all the time," Marsh said. "It's helpful for folks to let us know what they see." |
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a very interesting subject... |
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stalhandske 08-Nov-21, 21:38 |
For one thing it demonstrates that fossil finds are not over! There is still a lot to be found 'down there'! |
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Earth is 4.5 billion years old, and plants may have colonized land as recently as 470 million years ago, most likely mosses and liverworts without deep roots. Vascular plants followed about 420 million years ago, but even for tens of millions of years after that, no plants grew more than about 3 feet (1 meter) off the ground. Before trees, Earth was home to fungi that grew 26 feet tall. From about 420 million to 370 million years ago, a mysterious genus of creatures named Prototaxites grew large trunks up to 3 feet (1 meter) wide and 26 feet (8 meters) in height. Scientists have long debated whether these were some kind of weird ancient trees, but a 2007 study concluded they were fungi, not plants. "A 6-meter fungus would be odd enough in the modern world, but at least we are used to trees quite a bit bigger," study author and paleobotanist C. Kevin Boyce told New Scientist in 2007. "Plants at that time were a few feet tall, invertebrate animals were small, and there were no terrestrial vertebrates. This fossil would have been all the more striking in such a diminutive landscape." The first known tree was a leafless, fern-like plant from New York. Several kinds of plants have evolved a tree form, or "arborescence," in the past 300 million years or so. It's a tricky step in plant evolution, requiring innovations like sturdy trunks to stay upright and strong vascular systems to pump up water and nutrients from the soil. The extra sunlight is worth it, though, prompting trees to evolve multiple times in history, a phenomenon called convergent evolution. The earliest known tree is Wattieza, identified from 385 million-year-old fossils found in what's now New York. Part of a prehistoric plant family thought to be ancestors of ferns, it stood 26 feet (8 meters) tall and formed the first known forests. It may have lacked leaves, instead growing frond-like branches with "branchlets" resembling a bottlebrush (see illustration). It wasn't closely related to tree ferns, but did share their method of reproducing by spores, not seeds. Scientists thought this dinosaur-era tree went extinct 150 million years ago — but then it was found growing wild in Australia. During the Jurassic Period, a genus of cone-bearing evergreen trees now named Wollemia lived on the supercontinent Gondwana. These ancient trees were long known only from the fossil record, and were thought to have been extinct for 150 million years — until 1994, when a few survivors of one species were found living in a temperate rainforest at Australia's Wollemia National Park. That species, Wollemia nobilis, is often described as a living fossil. Only about 80 mature trees are left, plus some 300 seedlings and juveniles, and the species is listed as critically endangered by the International Union for Conservation of Nature. While Wollemia nobilis is the last of its genus, there are also still other middle Mesozoic trees alive today. Ginkgo biloba, aka the ginkgo tree, dates back about 200 million years and has been called "the most ancient living tree." |
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Riaan My brother and I used to find trilobites by the hand-full when we were in the boy scouts. en.wikipedia.org I |
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stalhandske 20-Nov-21, 22:03 |
<Your definition of “religious fanatic” is someone who doesn’t believe in the theory of evolution, which puts thousands of scientists, many of whom have far greater credentials and qualifications than you, under your heading of “fanatic.”> You clearly don't understand whom you are talking to. I say 'fanatic' for the simple reason that you represent a vanishingly small minority of Christians, as I have pointed out repeatedly. No, that does not in itself say you are 'wrong', but relative to the vast Christian majority, you are the fanatic. <You’re the fanatic, stalhandske. You can’t see the theory of evolution for the evidence-free garbage that it is. But many scientists do. And one day, likely soon, Darwin’s garbage theory will be revealed as the biggest scientific fraud of the 20th- and 21st centuries.> That's just your repeated mantra. I have responded to every single point of criticisim you have made, but those responses aren't acknowledged by you and just ignored. By contrast, I have seriously considered every one of your objections. <You’ve lived your life believing and working for a lie, stalhandske. And you’ve done it because you abandoned science and the scientific method! > Wow! This is kind of gross. But I really don't give a damn and won't use further bad language, because I know the qualities of the opponent. |
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6 meter mushrooms!! From about 420 million to 370 million years ago, a mysterious genus of creatures named Prototaxites grew large trunks up to 3 feet (1 meter) wide and 26 feet (8 meters) in height. Scientists have long debated whether these were some kind of weird ancient trees, but a 2007 study concluded they were fungi, not plants. "A 6-meter fungus would be odd enough in the modern world, but at least we are used to trees quite a bit bigger," study author and paleobotanist C. Kevin Boyce told New Scientist in 2007. "Plants at that time were a few feet tall, invertebrate animals were small, and there were no terrestrial vertebrates. This fossil would have been all the more striking in such a diminutive landscape. |
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Domestic Horse origins Domestic horses' mysterious origins may finally be revealed About 4,200 years ago, horseback riding allowed people to travel farther and faster than ever before, spurring migration throughout Europe and Asia. For thousands of years, horses have played critical roles in human societies around the world. These equines helped early farmers plow their fields, transported people farther and faster, and gave warriors a competitive edge in battle. But experts have long puzzled over the deceptively simple question of where domestic horses actually came from. It took a two-continent collaboration among over a hundred scientists to home in on the answer: southern Russia. The discovery provides strong evidence that of three main locations in contention—Anatolia, Iberia, and western Eurasian steppes—the last is likely the birthplace of modern domestic horses, Equus caballus. Study leader Ludovic Orlando, a molecular archaeologist at University Paul Sabatier in Toulouse, France, and colleagues reconstructed ancient horse genomes from ancient horse skeletons found in sites ranging from Portugal to Mongolia. One region in southern Russia, near the intersection of the Volga and Don Rivers, stood out. The cattle-herding region already had indirect archaeological evidence of horse domestication, but the new DNA research now shows that modern domestic horses can be traced to equines living here between 4,700 and 4,200 years ago. Because people in the Volga-Don region bred horses for domestication and quickly began migrating to new places with them, this new line of horses soon spread from western Europe to eastern Asia and beyond. The migration “was almost overnight,” says Orlando, whose study was published on October 20 in Nature. “This was not something that built up over thousands of years.” “As they expanded, they replaced all the previous lineages that were roaming around Eurasia,” he says. The domestic horse we know today “is the winner, the one we see everywhere, and the other types are sort of the losers.” (Learn how horses communicate with one another.) What’s more, horseback riding and horse-drawn war chariots, which were common a few hundred years after the equines’ domestication, changed the power dynamics between societies and likely further spurred the spread of the new horse. Building a better horse In Bronze Age Europe and Asia, about 5,000 to 4,200 years ago, people were probably domesticating horses. E. caballus evolved from short, horse-like grazers that roamed North American grasslands as early as the Eocene epoch (which began about 56 million years ago) and crossed over the Bering land bridge during the last ice age. Archaeological and historical records suggest that quite suddenly, around 4,200 years ago, horse populations mysteriously shot up across Eurasia. Was climate change expanding grasslands and giving horses more habitat? Were people across the world breeding herds at the same time? Or did these domesticated horses share a common source? Only in the last decade or so has the technology to test ancient DNA from preserved materials such as bones and hair become finely honed enough to investigate such broad questions. For their research, Orlando and an international team of bone collectors scoured museums and archaeological sites, ultimately gathering enough material to test 273 individual genomes from horse remains found across Europe and central Asia. By comparing the overall composition of the genomes across time and space, they were able to map out when and where horses’ gene pools evolved. (Read about wild horses and their shrinking population in the American West.) The genetic maps revealed a wide diversity among domesticated horses before about 5,000 years ago, which soon narrowed as humans began selectively breeding the animals for traits such as endurance, docility, and the ability to bear human weight—creating genetic tweaks that led to the horse we know today. The People of the Horse Horses changed life on the Great Plains forever, shaping everything from hunting methods to social status. For Native Americans today, horses endure as an emblem of tradition and a source of pride, pageantry, and healing. The study “finally provides genetic evidence from horses that lived in the relevant [time frame] and the right region,” says Vera Warmuth, a biologist at Ludwig-Maximillans University of Munich, in Germany, whose research models identified Volga-Don as a potential source for horse domestication over a decade ago. “Our own work predicted a rapid spread out of this area, and this is what this paper also suggests,” Warmuth wrote in an email. A shared history Communities across Eurasia already familiar with horses could have accelerated the expansion of the Volga-Don horse, says Kate Kanne, an archaeologist at the U.K.’s University of Exeter who was not involved in the study. “I think it happened quickly because those infrastructures were already in place, and at least some people had knowledge of horse husbandry,” Kanne says. As domesticated horses spread following the Bronze Age, humans traveled longer distances than ever before, leading to increased trade and transfer of knowledge between societies, as well as mobility. And when people moved, they brought their horses with them, Orlando says. (Read how horses and dogs share a language of play.) He calls it “the first experiment of globalization. The world became smaller, simply because we had the horse.” For instance, some of the earliest evidence of horse domestication comes from the Bronze Age Sintashta culture in southern Russia, where the discovery of horse remains along, with ancient wheels, hint at the equines’ importance for transportation. Not only that, but the timing of human genomic evolution in parts of Eurasia closely mirrors that of horses. “The history of humans is wrapped up in horse DNA,” Kanne says. The relationship between people and their horses is “really interesting to me… it tells the story of both our species in DNA.” |
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Disputed Claim First, a religious fanatic would be exemplified by someone who rejects science in favor of religious mythology. There may be other types of religious fanatic, but like the various disease pathologies, this type bears characteristic symptoms. Second, there are very few if ANY professional biologists with greater qualifications than Stalhandske who also reject evolution. I know many biologists, only one of whom embraces the idea evolution does not fully explain the origin of species. He does not reject evolution, he just believes that in addition another theory is required--a theory as yet to be proposed. His qualifications are pretty good--close to on par with those of Stalhandske. But odds are also pretty good that in the decade since that conversation (he was to testify at the Dover trial) he has abandoned Dembski's black box belief and now fully accepts the explanatory power and efficacy of evolutionary theory in accounting for life's development on our world. I only know this guy because my roommate in college, a professional microbiologist, is a colleague. |
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Horse evolution www.britannica.com The evolutionary lineage of the horse is among the best-documented in all paleontology. The history of the horse family, Equidae, began during the Eocene Epoch, which lasted from about 56 million to 33.9 million years ago. During the early Eocene there appeared the first ancestral horse, a hoofed, browsing mammal designated correctly as Hyracotherium but more commonly called Eohippus, the “dawn horse.” Fossils of Eohippus, which have been found in both North America and Europe, show an animal that stood 4.2 to 5 hands (about 42.7 to 50.8 cm, or 16.8 to 20 inches) high, diminutive by comparison with the modern horse, and had an arched back and raised hindquarters. The legs ended in padded feet with four functional hooves on each of the forefeet and three on each of the hind feet—quite unlike the unpadded, single-hoofed foot of modern equines. The skull lacked the large, flexible muzzle of the modern horse, and the size and shape of the cranium indicate that the brain was far smaller and less complex than that of today’s horse. The teeth, too, differed significantly from those of the modern equines, being adapted to a fairly general browser’s diet. Eohippus was, in fact, so unhorselike that its evolutionary relationship to the modern equines was at first unsuspected. It was not until paleontologists had unearthed fossils of later extinct horses that the link to Eohippus became clear. evolution of the horse evolution of the horse Evolution of the horse over the past 55 million years. The present-day Przewalski's horse is believed to be the only remaining example of a wild horse—i.e., the last remaining modern horse to have evolved by natural selection. Numbered bones in the forefoot illustrations trace the gradual transition from a four-toed to a one-toed animal. Encyclopædia Britannica, Inc. Eohippus Eohippus Eohippus, in an artist's conception. Existing toe bones of the forefoot are numbered outward from the centre of the body. Officially, taxonomists have classified this extinct mammal, which is considered to be the first known horse, in the genus Hyracotherium. Encyclopædia Britannica, Inc. The line leading from Eohippus to the modern horse exhibits the following evolutionary trends: increase in size, reduction in the number of hooves, loss of the footpads, lengthening of the legs, fusion of the independent bones of the lower legs, elongation of the muzzle, increase in the size and complexity of the brain, and development of crested, high-crowned teeth suited to grazing. This is not to imply that there was a steady, gradual progression in these characteristics leading inevitably from those of Eohippus to those of the modern horse. Some of these features, such as grazing dentition, appear abruptly in the fossil record, rather than as the culmination of numerous gradual changes. Eohippus, moreover, gave rise to many now-extinct branches of the horse family, some of which differed substantially from the line leading to the modern equines. Hyracotherium, or Eohippus Hyracotherium, or Eohippus A specimen of Hyracotherium discovered in the Green River Formation at Fossil Butte National Monument in Wyoming. Hyracotherium, often called Eohippus (“dawn horse”), is the oldest known member of the horse lineage. Arvid Aase—James E. Tynsky collection/U.S. National Park Service Britannica Demystified Why Do Horses Sleep Standing Up? And how do they do it? Although Eohippus fossils occur in both the Old and the New World, the subsequent evolution of the horse took place chiefly in North America. During the remainder of the Eocene, the prime evolutionary changes were in dentition. Orohippus, a genus from the middle Eocene, and Epihippus, a genus from the late Eocene, resembled Eohippus in size and in the structure of the limbs. But the form of the cheek teeth—the four premolars and the three molars found in each half of both jaws—had changed somewhat. In Eohippus the premolars and molars were clearly distinct, the molars being larger. In Orohippus the fourth premolar had become similar to the molars, and in Epihippus both the third and fourth premolars had become molarlike. In addition, the individual cusps that characterized the cheek teeth of Eohippus had given way in Epihippus to a system of continuous crests or ridges running the length of the molars and molariform premolars. These changes, which represented adaptations to a more-specialized browsing diet, were retained by all subsequent ancestors of the modern horse. Fossils of Mesohippus, the next important ancestor of the modern horse, are found in the early and middle Oligocene of North America (the Oligocene Epoch lasted from about 33.9 million to 23 million years ago). Mesohippus was far more horselike than its Eocene ancestors: it was larger (averaging about 6 hands [about 61 cm, or 24 inches] high); the snout was more muzzlelike; and the legs were longer and more slender. Mesohippus also had a larger brain. The fourth toe on the forefoot had been reduced to a vestige, so that both the forefeet and hind feet carried three functional toes and a footpad. The teeth remained adapted to browsing. By the late Oligocene, Mesohippus had evolved into a somewhat larger form known as Miohippus. The descendants of Miohippus split into various evolutionary branches during the early Miocene (the Miocene Epoch lasted from about 23 million to 5.3 million years ago). One of these branches, known as the anchitheres, included a variety of three-toed browsing horses comprising several genera. Anchitheres were successful, and some genera spread from North America across the Bering land bridge into Eurasia. Miohippus Miohippus The ancestral horse Miohippus, in an artist's conception. Existing toe bones of the forefoot are numbered outward from the centre of the body. Encyclopædia Britannica, Inc. It was a different branch, however, that led from Miohippus to the modern horse. The first representative of this line, Parahippus, appeared in the early Miocene. Parahippus and its descendants marked a radical departure in that they had teeth adapted to eating grass. Grasses were at this time becoming widespread across the North American plains, providing Parahippus with a vast food supply. Grass is a much coarser food than succulent leaves and requires a different kind of tooth structure. The cheek teeth developed larger, stronger crests and became adapted to the side-to-side motion of the lower jaw necessary to grind grass blades. Each tooth also had an extremely long crown, most of which, in the young animal, was buried beneath the gumline. As grinding wore down the exposed surface, some of the buried crown grew out. This high-crowned tooth structure assured the animal of having an adequate grinding surface throughout its normal life span. Adaptations in the digestive tract must have occurred as well, but the organs of digestion are not preserved in the fossil record. The change from browsing to grazing dentition was essentially completed in Merychippus, which evolved from Parahippus during the middle and late Miocene. Merychippus must have looked much like a modern pony. It was fairly large, standing about 10 hands (101.6 cm, or 40 inches) high, and its skull was similar to that of the modern horse. The long bones of the lower leg had become fused; this structure, which has been preserved in all modern equines, is an adaptation for swift running. The feet remained three-toed, but in many species the footpad was lost, and the two side toes became rather small. In these forms, the large central toe bore the animal’s weight. Strong ligaments attached this hoofed central toe to the bones of the ankles and lower leg, providing a spring mechanism that pushed the flexed hoof forward after the impact of hitting the ground. Merychippus gave rise to numerous evolutionary lines during the late Miocene. Most of these, including Hipparion, Neohipparion, and Nannippus, retained the three-toed foot of their ancestors. One line, however, led to the one-toed Pliohippus, the direct predecessor of Equus. Pliohippus fossils occur in the early to middle Pliocene beds of North America (the Pliocene Epoch lasted from about 5.3 million to 2.6 million years ago). Merychippus Merychippus The ancestral horse Merychippus, in an artist's conception. Existing toe bones of the forefoot are numbered outward from the centre of the body. Encyclopædia Britannica, Inc. fossil molar of Merychippus fossil molar of Merychippus The grooves on the fossil molars of Merychippus suggest that the species used its teeth to grind up grasses rather than leaves and fruits. Encyclopædia Britannica, Inc. Equus—the genus to which all modern equines, including horses, asses, and zebras, belong—evolved from Pliohippus some 4 million to 4.5 million years ago during the Pliocene. Equus shows even greater development of the spring mechanism in the foot and exhibits straighter and longer cheek teeth. This new form was extremely successful and had spread from the plains of North America to South America and to all parts of the Old World by the early Pleistocene (the Pleistocene Epoch lasted from about 2,600,000 to 11,700 years ago). Equus flourished in its North American homeland throughout the Pleistocene but then, about 10,000 to 8,000 years ago, disappeared from North and South America. Scholars have offered various explanations for this disappearance, including the emergence of devastating diseases or the arrival of human populations (which presumably hunted the horse for food). Despite these speculations, the reasons for the demise of Equus in the New World remain uncertain. The submergence of the Bering land bridge prevented any return migration of horses from Asia, and Equus was not reintroduced into its native continent until the Spanish explorers brought horses in the early 16th century. During the Pleistocene the evolution of Equus in the Old World gave rise to all the modern members of the genus. The modern horse, Equus caballus, became widespread from central Asia to most of Europe. Local types of horses, all breeds of this single species, undoubtedly developed, and three of these—Przewalski’s horse (E. ferus przewalskii or E. caballus przewalskii) from central Asia, the tarpan from eastern Europe and the Ukrainian steppes, and the forest horse of northern Europe—are generally credited as being the ancestral stock of the domestic horse. (Przewalski’s horse may be the last surviving distinct breed of wild horse when compared genetically with domesticated horses.) According to this line of thinking, Przewalski’s horse and the tarpan formed the basic breeding stock from which the southerly “warm-blooded” horses developed, while the forest horse gave rise to the heavy, “cold-blooded” breeds. |
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Eh? LOL. This could be dismissed as a case of the pot calling the kettle black, save that here the kettle is copper, not cast iron like the pot. How does A get under your skin? It is like you have never encountered a conspiracy loon before. In order to reject science, particularly biological science, one would have to swallow the notion all Earth's geologists, nuclear physicists, astronomers, paleontologists, and biologists are engaged in a vast conspiracy to hoodwink rational, intelligent, thoughtful people into rejecting stone age mythology. In all honesty, far more creationists have come to the realization creationism is a crock and have embraced science and rationality than there are so-called "creation" scientists. I know this because I am one. I was a creationist in my teen years, and my epiphany occurred in a class on raptor biology. The professor mentioned the evolution of traits quite as an aside to his regular lecture, and wham. I realized evolution had to be right. Not that a deity could not have guided the course of evolution, but without question evolution occurred. Then you see the tree of life, and you recognize the indisputable fact earthly organisms share common ancestry. All eukaryotes. That fact is inescapable. That fact is richly encoded into our very DNA. One might as easily reject the notion DNA serves as a recipe for "make organism" as to reject the pristine beauty of biological change wrought by coupling imperfect replication with environmental selection. Evolution=RM+NS. I'm carving this beauty into the bark of a tree. It is not remotely conceivable. |
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Of course It’s naive beyond belief to think life doesn’t change. The two most certain things we know about life is that it invariably ends in death and that it changes to fill every available niche. |
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Besides Of course, if anyone had a reasonable alternative. I’d be happy to hear it. *Crickets* |
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Evolution Alternative 170 years and no one has been up to the challenge? not a single solitary contender? Sad. It doesn't have to be based on stone age mythology. ANY contender... Actually, I used to debate a guy who was NOT a creationist, but instead a saltationist. He handle was "Salty.". He dismissed evolution, but his alternative theory was really weak. He had apparently been a professor of biology. A fairly smart guy. It would have been interesting to read his thesis, had he ever bothered to write one up. |
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Alternate theory |
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Zorro Creationism, on the other hand, is bunk. It is supported by a single fact--the gross misinterpretation of ancient scrolls. The Jews, holders of those sacred texts, dispute the nonsensical interpretation of their works by modern literalists, as does the Catholic church hierarchy. So how did creationism catch hold of the minds of a gullible segment of the population? Indoctrination is a powerful tool. |
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Shiva Well... at least we know THAT explanation exemplifies scientific thinking and processes... At least the way SOME ‘understand’ science. 🤪 |
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