Who's Who in Human Evolution. Despite a fragmentary fossil record augmented by rare, sometimes surprising new finds like Homo floresiensis, paleoanthropologists have. Where We Have Been; Where We Can Go. Energy. and the Human Journey: Where We Have Been; Where We Can Go. By Wade Frazier. Version 1. May 2. 01. 5. Professor and Brian, two great men whom. Buckminster. Fuller. I realize that almost nobody on Earth today can pass the. I do not ask. that of anybody whom I will attempt to recruit into my upcoming effort. Below is a diagram of. Buckminster Fuller. For that simplest element, hydrogen, its lone electron has an affinity to pair. First large- scale energy users. Deep oceans oxygenatedc. Creates conditions for complex life to appear, first in the global. Hominid Group, Diet, and Tool Use Some Genera and Species Included Fossil Finds Dates Evolutionary Fate; Gracile australopithecines: omnivorous diet with little tool. Analysis of Early Hominins. The bones of more than 500 early hominins have been found. From them, we have gained a broad understanding of these related species. Introduction. The discussion of our species, Homo sapiens, is probably the most difficult to put together. Whereas in the previous species have been introduced with. Despite this, there is little consensus on what our family tree is. Everyone accepts that the robust australopithecines (aethiopicus, robustus and boisei) are not. Cambrian Explosion beginsc. First complex ecosystems appear. Teeth appearc. 5. Concentrated application of muscle energy. Reef ecosystems. appearc. The most complex aquatic ecosystem appears. Land plants appearc. Energetic basis for land- based ecosystems appears. Land animals appearc. Ability to create non- aquatic ecosystems. Jaws appearc. 4. 20 mya. Greatest energy manipulation enhancement among vertebrates until the. Vascular plants appearc. Ability to create vertical ecosystems. Trees appearc. 3. Largest organisms ever, and greatest energy storage and delivery to. Fish migrate to. landc. Precursor to dominant land animals. Seed- reproducing plants appearc. Ability to colonize dry lands. Amniotes appearc. Ability to survive in dry lands. Lignin- digesting organism appearsc. Ability to make tree- stored energy available to ecosystems. Dinosaurs appearc. Among the first terrestrial animals with upright posture, enabling. Tools first usedc. Confers energy advantage to tool user. Flowering plants appearc. Great energy innovation to reduce reproductive costs, and animals are. The control of firec. Allows protohumans to leave trees, become. Earth's dominant predator, alter. Projectile weapons inventedc. Allows for first low- energy transportation, and ability to travel to. Widespread domestication of plants and animalsc. Provides the local and stable energy supply that allowed for sedentary. First metal smeltedc. Allows for tools highly improved over stone, for greater energy effectiveness. Plow inventedc. 7 kya. Allows for greatly increased energy yields from agriculture. First sailboat inventedc. First technology to take advantage of non- biological energy. Wheel inventedc. 5. Reduces energy use for ground- based transportation. Coal first burnedc. First use of non- biomass for chemical energy. Iron first smeltedc. Allows for vastly improved tools. Coal used to smelt metalc. First use of non- biomass to smelt metal. Watermill inventedc. First time the energy of the hydrological cycle is harnessed for use. Windmill inventedc. First time wind is harnessed for use on land. Steam engine inventedc. First time the motive power of fire is harnessed. Europe learns to sail across the world's oceans. The years 1. 42. 0 . New way to use energy would revolutionize civilization. First commercial oil well drilled. The most coveted fuel of the Industrial Revolution is first used. Incandescent lighting first commercializedc. First commercial use of electricity. No land masses yet. Earth, Moon, and oceans form. ![]() Maps begin to be made with confidence at about 7. Earth. 8. 50 to 6. Late Cryogenian Map. Supercontinent. Rodinia breaks up. Mid- Ediacaran Map. Deep ocean is oxygenated. Late Cambrian Map. Continents primarily in Southern Hemisphere. Late Ordovician. Map. Paleo- Tethys Ocean begins forming. Mollusks proliferate and. Mid- Silurian Map. Hot, shallow seas dominate biomes. Late Devonian Map. Continents closing to form Pangaea, ice age begins at end of Devonian. Fishes thrive. 3. Early Carboniferous Map. End- Carboniferous. Map. Atmospheric oxygen levels highest ever, likely due to carbon sequestration. Late Permian Map. Tethys Ocean forms. Mid- Triassic Map. Pangaea begins to break up. Early Jurassic Map. Mid- Jurassic Map. Late Jurassic Map. Northern continents split from southern continents. Mid- Cretaceous Map. End- Cretaceous Map. Sea levels dramatically rise. Paleocene Climate Map. Greenhouse Earth conditions still prevail. Mid- Eocene Map. Late Eocene Map. Warmest epoch in hundreds of millions of years, but began cooling midway. Icehouse Earth conditions. Oligocene Climate Map. Cool epoch, as Antarctic ice sheets form. Mid- Miocene Map. First half of epoch is warm, then cools down. Would appear nearly identical to today. Early Pleistocene. Map. Late- Pleistocene Map. Current ice age begins. Mammals already cold- adapted, and relatively few extinctions, until. By the 2. 1st century. Sixth Mass Extinction in the eon of complex. When a star becomes a supernova, those heavy elements are sprayed into the. When life first appeared, it was single- celled and simple. Ediacaran fossils have been found in a few. Readers for the collective task that I have in mind need to become familiar. FE and other fringe. Unknown, but almost all Ediacaran forms disappeared. Anoxia Cambrian Explosion Mid- Cambrianc. Unknown, but small shelly fauna largely disappear. Anoxia. End of Golden Age of Trilobites. Unknown, but half of trilobite species go extinct. Temperature and sea level changes and anoxia. Ecosystem functioning not fundamentally altered. Climate and sea level changes. Seafloor communities devastated. Climate change, sea level changes, and anoxia. Seafloor communities devastated. Climate change, sea level changes, and anoxia. Late Devonian c. Series of extinctions. Marine extinction. Sea level changes related to ice age and continental uplift related. Pangaea. 3. 07 mya. Rainforest collapse. Ice age. The rise of reptiles. Permian. 2. 70 to 2. Series of extinctions. Ammonoid and conodont mass extinction. Volcanism, warming, sea level changes, and anoxia. The dominance of dinosaurs. Reefs and ammonites devastated. Volcanism, anoxia. Carbonate hardgrounds become common in calcite. Reef collapse, bivalves had about a 2. Falling sea levels. Cretaceous period rise of ornithischians. Marine event. 9. 3 mya. Marine event which may have marked the final extinction of ichthyosaurs. Bolide impact, and perhaps also volcanism and sea level changes. The end of dinosaurs and the rise of mammals. Seafloor communities devastated, up to 5. Volcanism, release of methane hydrates from. Warm- climate species migrate or go extinct. Half of European mammal genera, all. Migration of Asian mammals to Europe, Icehouse. Earth conditions in oceans. Relatively cold Oligocene Epoch begins. Warm- climate species migrate or go extinct. North American bivalve species, Florida. The majority of mammalian species. May reach 5. 0% or higher by 2. Source: Wikimedia Commons) (map with names is here)Chapter summary: Until Ediacaran fossils were recognized for what they were, the Cambrian Period (c. Darwin onward. An irony of fossilization is that conditions hostile to life usually left the best- preserved. Around 5. 30 mya, the first brachiopods, reef- building animals, and. Source: Wikimedia Commons) (map with names is here)Chapter summary: With the extinction that ended the Cambrian Period, animal life. Source: Wikimedia Commons) (map with names is here)World map at end of Carboniferous Period (c. Source. Wikimedia Commons) (map with names is here)World map in late Permian Period (c. Source: Wikimedia Commons) (map. Chapter summary: The period succeeding the Devonian is called the. Carboniferous (c. Artists have been depicting Carboniferous swamps for more than a century, and. In the oceans, the Carboniferous is called the Golden Age. Sharks, and ray- finned fish arose to a ubiquity that they have yet to fully. In the early Carboniferous, the continents were still somewhat dispersed. Pangaea. 2. 99 to 2. Source: Wikimedia Commons) (map with names is here)World map in mid- Cretaceous (c. Source: Wikimedia Commons) (map. Chapter summary: The period following the greatest extinction event ever is called the Triassic (c. Cretaceous (c. 1. Golden Age of Dinosaurs. In the late Jurassic, as ornithischians began to become. Cretaceous extinction: birds. In the late Jurassic, armored stegosaurs and ankylosaurs. Cretaceous, which reached its peak with Triceratops in the late. Cretaceous. 1. 45 to 6. It is probably safe to say that if the end- Cretaceous extinction had multiple. Source: Wikimedia Commons) (map with names is here)World map in early- Miocene (c. Source: Wikimedia Commons). Chapter summary: As smoke cleared and dust settled, literally, from the. Compared to the recovery from the mass extinctions that ended the Devonian. Permian, and Triassic. Cretaceous extinction was relatively swift. Among herbivores, their mode of digestion was important. PETM, is also known as. Earth. For several million years, life in the Eocene was halcyonic. Greenhouse. Earth state had prevailed ever since the end- Permian. In recent years, Neogene temperatures have been. Megalodon was not far behind. Buckminster. Fuller's pupils remarked that my work was like Fuller's, and. I had been groping. Public is only interested in FE technology to the extent. Unicellular organisms. First multicellular organism. Was probably sponge- like. Motile animals. Flatworm. First animal with a brain. Worms. Acorn worm. Early animals with breathing and circulatory systems. Fish- like ancestors to vertebrates. Pikaia. First animal with a spinal cord. Eel- like fish. Ostracoderm. First true fish. 5. Jawless fish. Placoderm. First fish with jaws. Cartilaginous fish. Guiyu oneiros. First bony fish. Bony fish. Coelacanth. First fish with lobed fins, which later became legs. Lobe- finned fish. Panderichthys. First fish that begins developing legs. Leggy fish. Tiktaalik. First fish to crawl on land. Crawling fish. Ichthyostega. First fish to walk on land. Tetrapods. Acanthostega. First amphibian. c. Amphibians. Hylonomus. First reptile. 3. Reptiles. Archaeothyris. First synapsid. c. Synapsids. Sphenacodonts (AKA pelycosaurs)Lost its scales, and teeth begin to become specialized. Pelycosaurs. Raranimus. First therapsid. 2. Therapsids. Theriodonts. May have been warm- blooded. Theriodonts. Cynodonts. Jaws changed, freeing up bones to eventually form. Cynodonts. Tritheledontids. More mammalian traits than reptilian. Tritheledontids. Mammaliaformes. Homo sapiens - H. Whereas in the previous species have been introduced with historical background and a discussion of the early, most important finds, and the individuals responsible for the species designation, this introduction will focus on some of the theory implicit in the discussion of the origin and spread of H. Others (such as Milford Wolpoff), take the view that our species extends as far as approximately 2. H. There are two polarizing camps on the issue of our species origin (though there is varying degrees of compromise between the two stances as well as various alternative positions): the multiregional (or continuity) camp, and the Out of Africa (replacement) camp. The perspective of multiregionalists is that extending to the origin of H. In this scenario, the Chinese and Indonesian material are the most direct ancestors of modern East Asians, the African material are the most direct ancestors of modern Africans, and that either the European populations are the most direct ancestors of modern Europeans, or that the European populations contributed significant genetic material to modern Europeans, with most of modern Europeans origins rooted in Africa or West Asia. Adherents to this model look at early material and try to trace continuity in morphology from those early populations to later populations in the same geographic area. In this model, there are paralleled changes in all penecontemporary populations, with enough genetic migration to maintain close species bonds, while still allowing the suite of racial features we see today. The perspective of the Out of Africa model (often called Out of Africa II, referring to a second migration from Africa of a hominid population) adherents is that when there was a migration of H. At approximately 2. Africa. This time it was fully modern H. Some see direct competition and extermination of the native populations, some see passive replacement due to better adaptive strategies, and some see genetic admixture with the preponderance of genetic material coming from the incoming human populations, eventually replacing and assimilating them into the greater collective. In this view there is a specific speciation event that occurred which led to the origin of H. Multiregionalists look for similarities between populations in the same geographic location that are separated spatially, while people who follow replacement look for differences. It is oft a difference of semantics between different interpretations rather than real differences of opinion, but often there is real disagreement on the validity of research, and theoretical interpretations. This has led to some fairly severe strife within the paleoanthropological community, with potshots often taken unfairly at rival theories and rival theoreticians. For example, multiregionalism is often portrayed as a racist theory that claims different “races” have evolved to different “levels” of intelligence. Out of Africa II has often been portrayed as a religiously motivated idea that tries to come to terms with the biblical story of Genesis, as reference to the “Eve” theory suggests. Beyond disagreement over fundamental issues like “What is a valid speciation event?” one fact stands out: neither theory has proved itself above the other in terms of parsimonious explanation of the fossil evidence. The general opinion among researchers seems to go in cycles, supporting Oo. A, then supporting MRE, then supporting Oo. A, etc. Currently, we seem to be at a cusp of support for replacement, and there seems top be a shifting in opinion more favorable to continuity. The highly publicized genetic studies that purportedly “proved” that Neanderthals did not contribute the modern human genome are so plagued with practical and theoretical problems to make their conclusions moot, especially since it does not in any way address the rest of the populations in the world, and their genetic fate. Diagnostic Features. Europe. No part of these descriptions will favor one camp over the other; this being said, multiregionists have a very valid criticism of the supposed lack of any evidence of continuity between earlier and later fossil groups in geographic regions. This certainly holds true for Europe, where the perceived differences between the earlier Neanderthal populations and later “modern” H. There are many sites which are attributed to what are called “early modern humans” are not always particularly older than “fully” modern humans, nor later than Neanderthal sites. As discoveries have continued over the last century Neanderthals are now clearly associated with Upper Paleolithic sites, and “modern” humans are no longer an Upper Paleolithic phenomenon. The history of the interpretation of the European fossil record is marred by the fact that early attempts to demonstrate continuity by researchers such as A. Hrdlicka and G. Schwalbe were troubled by misdated specimens and faulty reconstructions, while early attempts to demonstrate replacement were based on the Piltdown hoax and the misdated Galley Hill material. These problematic foregrounds for further interpretation were also built upon by the faulty “type” approach of early paleoanthropologists, where La Chapelle was seen as a typical Neanderthal specimen and Cro- Magnon was seen as a typical early modern human. In fact, these two specimens are significantly atypical. Simple replacement and continuity models are beginning to fall apart, as the lines between earlier and later populations blurs in some respects and becomes more demarked in others. Two major lines of thinking exist regarding the origins of modern humans in Europe: Neanderthals contributed some amount of significant genetic material to later modern human populations, or they did not. There are three major lines of evidence arguing for continuity, including: The evolution of the pre- Neanderthal and Neanderthal populations over time is in the direction of modern European populations. These trends include: anterior dental reduction, reduced nasal size, increased central and decreased lateral browridge height, and more developed mental eminences. European Neanderthals show a number of unique or especially common features with later Europeans, with lower frequency of expression in modern European populations. No other penecontemporary population shares unique features with the later Europeans. While some may argue the third point, it is not clearly correct or incorrect, and the first two points are definite. In contrast, the evidence for lack of continuity is expressed in the following points: Early modern Europeans show limb proportions that are closely linked to warm- adapted African populations, and not with European Neanderthals. Genetic evidence in the form of mt. DNA studies purporting to show evidence of Neanderthal and modern human divergence at approximately 7. DNA variation in African populations, which is claimed evidence for African origin of modern humans. Behavioral differences between the Neanderthals and early modern humans in both absolute traits and complexity. The genetic evidence is very suspect, and the theoretical and practical problems with such undertakings will continue to place such evidence as circumstantial at best for at least the next five to ten years. The behavioral evidence is an old one, and is crumbling into dust as paleoanthropology enters the 2. There likely were some behavioral differences between Neanderthal and later modern human populations, but there are many traits and sites linking the behaviors as developing – at least in part – from the former to the later. The limb proportion evidence, however, seems unmistakable. There was an influx of either populations or genetics into Europe with an African origin, though whether as a replacing invasion or a migration, with or without assimilation it is up in the air. Very possibly occurringat this time was assimilation of the Neanderthal populations with incoming early modern humans, with differential representation in the resulting genome on the modern human side. It is difficult to believe that the Neanderthal traits would evolve into the modern form without significant contribution of genes for more gracile features. And the limb proportion argument cannot be resolved without a migration of Africans either bodily or genetically. A description of European H. Discoveries of material from the site began in 1. J. Tragically, the material was destroyed at the end of World War II by the Nazis, along with many other archaeological materials such as the Predmost. The fossil material is associated with an early Central European Aurignacian industry. The material dates from c. The material consists of over 1. Mladec 5,6, and 4. The male specimens are very robust, and there is significant sexual dimorphism in terms of morphological variability. The three male crania are characterized by: Low braincases. Thick cranial bones. Posterior cranial flattening forming a Neanderthal- like occipital bun. Marked spongy bone development. Thick projecting supraorbitals (shaped differently than in Neanderthals). Large cranial capacities (1. However, compared to more modern humans they are very robust, almost as robust as later Upper Paleolithic males. This population shows a reduction in the difference between male and female brain size relative to the Neanderthal condition. The females (Mladec 1 and Mladec 2) show cranial capacities of 1. This has been taken as evidence of lack of Neanderthal ancestry, as well as evidence that the Neanderthal populations were evolving into the modern form. The Mladec females show both similarities and differences from the earlier Neanderthal females, including: Larger cranial vault size. More midfacial prognathism. More anterior zygomatics. Lack a maxillary notch. A considerably narrower nose. Presence of a distinct canine fossa. As noted before, there are some marked differences between the Mladec males and females. The systematic sexual differences include: Larger cranial vaults in the males (1.
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