genetic evidence indicates that ancient protists evolved from
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- Genetic evidence (base sequences in their mitochondrial deoxyribonucleic acid [mtDNA] and ribosomal ribonucleic acid [rRNA]) now indicates that the following are more natural (evolutionarily related) groups of Protista.ome lack mitochondria and suggest what the first eukaryotes may have been like, while others have primitive mitochondria that closely resemble bacteria. Some basal Protista without mitochondria are Trichomonas, a vaginal parasite of humans; Giardia, an intestinal parasite; and Entamoeba, the cause of amoebic dysentery.
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Protist Protists were traditionally subdivided into several groups based on similarities to the higher kingdoms: the unicellular animal-like protozoa, the plant-like protophyta (mostly unicellular algae), and the fungus-like slime molds and water molds.mong the pioneers in the study of the protists, which were almost ignored by Linnaeus except for some algae, were Leeuwenhoek, O. F. Mueller, Müller. C. G ehrenberg And Felix. Félix dujardin the first groups used to classify microscopic organism Were the animalcules And. the infusoria
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Life Science: Session 4 There is overwhelming evidence that the ancestors of modern land plants evolved in aquatic environments, where they existed and diversified over millions of years. From one group of these organisms — probably ancestors of modern species of protists known as green algae — emerged a new branch on the tree of life.ody support As plants evolved from aquatic to terrestrial environments, several obstacles stood in the way. One obstacle was structural support. In water, organisms are buoyant and the effects of gravity are minimal. Even among larger forms, like kelps, structures with gas-filled vesicles allow them to float.
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Genetic Data and Fossil Evidence Tell Differing Tales of Human Origins Geneticists studying DNA now say that, to the contrary, a previously unknown archaic species of human, a cousin of the Neanderthals, may have lingered in Africa until perhaps 25,000 years ago, coexisting with the modern humans and on occasion interbreeding with them.ll human fossil remains in Africa for the last 100,000 years, and probably the last 200,000 years, are of modern humans, providing no support for a coexistent archaic species.
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Genetic 'Adam' and 'Eve' uncovered And in a study detailed in March in the American Journal of Human Genetics, Hammer's group showed that several men in Africa have unique, divergent Y chromosomes that trace back to an even more ancient man who lived between 237,000 and 581,000 years ago.
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- The fossils from Piltdown, England, represent some of the most important evidence for the evolution of early humans in Europe. False The oldest recognizable artifacts are simple stone tools dating to about 2.6 mya and are referred to as the Oldowan Complex.
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AP Biology - Evolution Then in our college courses, we were introduced to five kingdoms: Monera, Protista, Plantae, Fungi, and Animalia. Now biologists have adopted a three-domain system, which consists of the domains Bacteria, Archaea, and Eukarya. This system arose from the finding that there are two distinct lineages of prokaryotes.hen in our college courses, we were introduced to five kingdoms: Monera, Protista, Plantae, Fungi, and Animalia. Now biologists have adopted a three-domain system, which consists of the domains Bacteria, Archaea, and Eukarya. This system arose from the finding that there are two distinct lineages of prokaryotes.
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Europeans drawn from three ancient 'tribes' The findings are based on analysis of genomes from nine ancient Europeans. Agriculture originated in the Near East - in modern Syria, Iraq and Israel - before expanding into Europe around 7,500 years ago. Multiple lines of evidence suggested this new way of life was spread by a wave of migrants, who interbred with the indigenous European hunter-gatherers they encountered on the way.
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Prokaryotic Diversity Prokaryotes arose during the Precambrian Period 3.5 to 3.8 billion years ago. Prokaryotic organisms can live in every type of environment on Earth, from very hot, to very cold, to super haline, to very acidic. The domains Bacteria and Archaea are the ones containing prokaryotic organisms. The Archaea are prokaryotes that inhabit extreme environments, such as inside of volcanoes, while Bacteria are more common organisms, such as E. coli.
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- Jake Bailey from the University of Minnesota and Philip Donoghue from University of Bristol negate the fact that the fossils represent bacteria, strengthening the theory that the fossils are either animals or some type of protist, possibly other than bacteria.
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Humans did come out of Africa, says DNA This genetic divide probably represents an exodus of people from Africa that took place 52,000 - 27,500 years ago. This evidence favouring the 'recent African origin' theory of human evolution is compelling, but the researchers hope for better data in the near future.
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Ancient origin of hepatitis B viruses revealed by DNA fossils in bird genomes Ancient origin of hepatitis B viruses revealed by DNA fossils in bird genomes. The hepatitis B virus originally infected birds back when the dinosaurs still roamed the planet, according to a newly published study of genomic bird DNA, a finding that may help improve human health outcomes.
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Human evolution Genetic studies show that primates diverged from other mammals about 85 million years ago, in the Late Cretaceous period, and the earliest fossils appear in the Paleocene, around 55 million years ago.
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Recent African origin of modern humans In paleoanthropology, the recent African origin of modern humans, or the out of Africa theory (OOA), is the most widely accepted model of the geographic origin and early migration of anatomically modern humans.ll other fossils of fully modern humans outside Africa have been dated to more recent times. The oldest well dated fossil of modern humans found outside Africa is from Manot Cave in Israel, named Manot 1, which have been dated to 54,700 years ago.
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Recent African origin of modern humans In paleoanthropology, the recent African origin of modern humans, or the out of Africa theory (OOA), is the most widely accepted model of the geographic origin and early migration of anatomically modern humans.owever, the rate of interbreeding was found to be relatively low (1–10%) and other studies have suggested that the presence of Neanderthal or other archaic human genetic markers in modern humans can be attributed to shared ancestral traits originating from a common ancestor 500,000 to 800,000 years ago.
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- Nuclear and mitochondrial DNA are thought to be of separate evolutionary origin, with the mtDNA being derived from the circular genomes of the bacteria that were engulfed by the early ancestors of today's eukaryotic cells.This theory is called the endosymbiotic theory.nlike nuclear DNA, which is inherited from both parents and in which genes are rearranged in the process of recombination, there is usually no change in mtDNA from parent to offspring.
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Ancient DNA analysis reveals Minoan and Mycenaean origins Ancient DNA analysis reveals Minoan and Mycenaean origins. August 2, 2017. The Minoans were a literate Bronze Age civilization that flourished thousands of years ago (one woman shown dancing, in a fresco fragment that dates from 1600-1450 BCE). An analysis of ancient DNA has revealed that Ancient Minoans and Mycenaens were genetically similar with both peoples descending from early Neolithic farmers.
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- The first fossils of early modern humans to be identified were found in 1868 at the 27,000-23,000 year old Cro-Magnon rock shelter site near the village of Les Eyzies in southwestern France. They were subsequently named the Cro-Magnon people.They were very similar in appearance to modern Europeans.t would be a mistake to assume that from the time modern Homo sapiens began migrating out of Africa that all people in that continent were modern humans. The video below presents evidence of pockets of archaic humans surviving in West Africa until at least 13,000 years ago.
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- Cyanobacteria (also known as blue-green algae), one of the earliest types of prokaryotic bacteria, formed into colonies or mats called stromatolites, and fossilized remains of these have been found in Australia dating back to between 3.4 and 2.8 billion years ago.
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Introduction to Trilobite Fossils - Trilobite Fossil Facts and Information Trilobites probably arose from a soft bodied ancestor in the Pre-Cambrian. The first actual trilobites fossils found are from the Cambrian. Based on the variety of Early Cambrian fossils and the wide distribution, trilobites probably evolved sometime in the Pre-Cambrian.Once Trilobites made their appearance, they dominated the Paleozoic seas, many new orders and families quickly appeared.rilobites probably arose from a soft bodied ancestor in the Pre-Cambrian. The first actual trilobites fossils found are from the Cambrian. Based on the variety of Early Cambrian fossils and the wide distribution, trilobites probably evolved sometime in the Pre-Cambrian.
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- Africans display higher genetic variation than other populations, supporting the idea that they were the first modern humans. 1  In support of an African origin for Homo sapiens the work of Cann and Wilson1 has demonstrated that the highest level of genetic variation in mtDNA occurs in African populations.
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Protist Historical classifications. Among the pioneers in the study of the protists, which were almost ignored by Linnaeus except for some genera (e.g., Vorticella, Chaos, Volvox, Corallina, Conferva, Ulva, Chara, Fucus) were Leeuwenhoek, O. F. Müller, C. G. Ehrenberg and Félix Dujardin. The first groups used to classify microscopic organism were the Animalcules and the Infusoria.
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Evolution of sexual reproduction The evolution of sexual reproduction describes how sexually reproducing animals, plants, fungi and protists evolved from a common ancestor that was a single celled eukaryotic species. There are a few species which have secondarily lost the ability to reproduce sexually, such as Bdelloidea and some parthenocarpic plants.exual reproduction has probably contributed to the evolution of sexual dimorphism, where organisms within a species adopted different strategies of parental investment.
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- Given that the alveolates, the dinoflagellates and the heterokont algae acquired their plastids from a red algae it seems likely that their ancestor was photosynthetic. 1  Li, C.-W.; et al. (2007).  2 alveolate. Memidex (WordNet) Dictionary/Thesaurus.
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- Pluricellular algae are also eukaryotes of simple structure. Protists are believed to be the phylogenetic ancestors of the living organisms of the other eukaryotic kingdoms (fungi, animals and plants).
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Human Evolution The fossils of these early hominids, which lived 2 to 6 million years ago, all come from that continent. Most scientists believe early humans migrated out of Africa into Asia between 2 million and 1.7 million years ago, entering Europe some time within the past 1 million years.omo sapiens. Scientists have dated the oldest known fossils with skeletal features typical of modern humans from 195,000 years ago. Early anatomically modern Homo sapiens fossils have come from sites in Sudan, Ethiopia, South Africa, and Israel.