- Levels of Taxonomy Used in Biology
- Human taxonomy
- Week 13: Introduction to small mammals
- Taxonomy and Organism Classification
- Taxonomy of Homo Sapiens
Levels of Taxonomy Used in BiologyHuman evolutionthe process by which human beings developed on Earth from now-extinct primates. Viewed zoologically, we humans are Homo sapiensa culture-bearing upright-walking species that lives on the ground and very likely first evolved in Africa aboutyears ago. We are now the only living members of what many zoologists refer to as the human tribe, Homininibut there is abundant fossil evidence to indicate that we were preceded for millions of years by other hominins, such as ArdipithecusAustralopithecusand other species of Homoand that our species also lived for a time contemporaneously with at least one other member of our genusH. In addition, we and our predecessors have always shared Earth with other apelike primates, from the modern-day gorilla to the long-extinct Dryopithecus. That we and the extinct hominins are somehow related and that we and the apesboth living and extinctare also somehow related is accepted by anthropologists and biologists everywhere. Yet the exact nature of our evolutionary relationships has been the subject of debate and investigation since the great British naturalist Charles Darwin published his monumental books On the Origin of Species and The Descent of Man There is theoretically, however, a common ancestor that existed millions of years ago. This ancient primate has not been identified and may never be known with certainty, because fossil relationships are unclear even within the human lineage, which is more recent. The answer to this question is challenging, since paleontologists have only partial information on what happened when. Strong evidence supports the branching of the human lineage from the one that produced great apes orangutans, chimpanzees, bonobos, and gorillas in Africa sometime between 6 and 7 million years ago. Evidence of toolmaking dates to about 3. However, the age of the oldest remains of the genus Homo is younger than this technological milestone, dating to some 2. The oldest known remains of Homo sapiens —a collection of skull fragments, a complete jawbone, and stone tools—date to aboutyears ago. Humans are one type of several living species of great apes. Humans evolved alongside orangutans, chimpanzees, bonobos, and gorillas. All of these share a common ancestor before about 7 million years ago. Neanderthals Homo neanderthalensis were archaic humans who emerged at leastyears ago and died out perhaps between 35, and 24, years ago. They manufactured and used tools including blades, awls, and sharpening instrumentsdeveloped a spoken languageand developed a rich culture that involved hearth construction, traditional medicineand the burial of their dead. Neanderthals also created art ; evidence shows that some painted with naturally occurring pigments. In the end, Neanderthals were likely replaced by modern humans H. The primary resource for detailing the path of human evolution will always be fossil specimens. Certainly, the trove of fossils from Africa and Eurasia indicates that, unlike today, more than one species of our family has lived at the same time for most of human history. The nature of specific fossil specimens and species can be accurately described, as can the location where they were found and the period of time when they lived; but questions of how species lived and why they might have either died out or evolved into other species can only be addressed by formulating scenarios, albeit scientifically informed ones. These scenarios are based on contextual information gleaned from localities where the fossils were collected. In devising such scenarios and filling in the human family bush, researchers must consult a large and diverse array of fossils, and they must also employ refined excavation methods and records, geochemical dating techniques, and data from other specialized fields such as geneticsecology and paleoecology, and ethology animal behaviour —in short, all the tools of the multidisciplinary science of paleoanthropology. This article is a discussion of the broad career of the human tribe from its probable beginnings millions of years ago in the Miocene Epoch 23 million to 5. Particular attention is paid to the fossil evidence for this history and to the principal models of evolution that have gained the most credence in the scientific community. See the article evolution for a full explanation of evolutionary theory, including its main proponents both before and after Darwin, its arousal of both resistance and acceptance in society, and the scientific tools used to investigate the theory and prove its validity. Human evolution. Article Media. Info Print Print. Table Of Contents. Submit Feedback. Thank you for your feedback. Introduction Background and beginnings in the Miocene Striding through the Pliocene The anatomy of bipedalism The fossil evidence Theories of bipedalism Hominin habitats Tools, hands, and heads in the Pliocene and Pleistocene Refinements in hand structure Increasing brain size Refinements in tool design Reduction in tooth size The emergence of Homo sapiens Language, culture, and lifeways in the Pleistocene Speech and symbolic intelligence Learning from the apes. See Article History. Top Questions. Homo sapiens. Load Next Page.
Taxonomyin a broad sense the science of classificationbut more strictly the classification of living and extinct organisms—i. Taxonomy is, therefore, the methodology and principles of systematic botany and zoology and sets up arrangements of the kinds of plants and animals in hierarchies of superior and subordinate groups. Among biologists the Linnaean system of binomial nomenclaturecreated by Swedish naturalist Carolus Linnaeus in the s, is internationally accepted. Popularly, classifications of living organisms arise according to need and are often superficial. Anglo-Saxon terms such as worm and fish have been used to refer, respectively, to any creeping thing—snake, earthworm, intestinal parasite, or dragon—and to any swimming or aquatic thing. Although the term fish is common to the names shellfishcrayfishand starfishthere are more anatomical differences between a shellfish and a starfish than there are between a bony fish and a man. Vernacular names vary widely. The American robin Turdus migratoriusfor example, is not the English robin Erithacus rubeculaand the mountain ash Sorbus has only a superficial resemblance to a true ash. Biologists, however, have attempted to view all living organisms with equal thoroughness and thus have devised a formal classification. A formal classification provides the basis for a relatively uniform and internationally understood nomenclature, thereby simplifying cross-referencing and retrieval of information. The usage of the terms taxonomy and systematics with regard to biological classification varies greatly. People who live close to nature usually have an excellent working knowledge of the elements of the local fauna and flora important to them and also often recognize many of the larger groups of living things e. Their knowledge, however, is according to need, and such people generalize only rarely. The first great generalizer in classification was Aristotlewho virtually invented the science of logic, of which for 2, years classification was a part. Greeks had constant contact with the sea and marine life, and Aristotle seems to have studied it intensively during his stay on the island of Lesbos. In his writings, he described a large number of natural groups, and, although he ranked them from simple to complex, his order was not an evolutionary one. He was far ahead of his time, however, in separating invertebrate animals into different groups and was aware that whales, dolphins, and porpoises had mammalian characters and were not fish. Lacking the microscope, he could not, of course, deal with the minute forms of life. The Aristotelian method dominated classification until the 19th century. His scheme was, in effect, that the classification of a living thing by its nature—i.
Week 13: Introduction to small mammals
The genus emerged with the appearance of Homo habilisjust over 2 million years ago. Homo erectus appeared about 2 million years ago and, in several early migrationsit spread throughout Africa where it is dubbed Homo ergaster and Eurasia. It was likely the first human species to live in a hunter-gatherer society and to control fire. An adaptive and successful species, Homo erectus persisted for more than a million years and gradually diverged into new species by aroundyears ago. Homo sapiens anatomically modern humans emerged close totoyears ago,  most likely in Africa, and Homo neanderthalensis emerged at around the same time in Europe and Western Asia. Both in Africa and Eurasia, H. Separate archaic non- sapiens human species are thought to have survived until around 40, years ago Neanderthal extinctionwith possible late survival of hybrid species as late as 12, years ago Red Deer Cave people. Even today, the genus Homo has not been stricly defined. The discovery of Neanderthal brought the first addition. The genus Homo was given its taxonomic name to suggest that its member species can be classified as human. And, over the decades of the 20th century, fossil finds of pre-human and early human species from late Miocene and early Pliocene times produced a rich mix for debating classifications. There is continuing debate on delineating Homo from Australopithecus —or, indeed, delineating Homo from Panas one body of scientists argues that the two species of chimpanzee should be classed with genus Homo rather than Pan. Many such names are now dubbed as " synonyms " with Homoincluding Pithecanthropus Protanthropus Sinanthropus Cyphanthropus Africanthropus Telanthropus Atlanthropus and Tchadanthropus. Classifying the genus Homo into species and subspecies is subject to incomplete information and remains poorly done. This has led to using common names "Neanderthal" and "Denisovan"even in scientific papers, to avoid trinomial names or the ambiguity of classifying groups as incertae sedis uncertain placement —for example, H. John Edward Gray was an early advocate of classifying taxa by designating tribes and families. Several species, including Australopithecus garhiAustralopithecus sedibaAustralopithecus africanusand Australopithecus afarensishave been proposed as the direct ancestor or sister of the Homo lineage. Especially since the s, the delineation of Homo in Australopithecus has become more contentious. Traditionally, the advent of Homo has been taken to coincide with the first use of stone tools the Oldowan industryand thus by definition with the beginning of the Lower Palaeolithic. But inevidence was presented that seems to attribute the use of stone tools to Australopithecus afarensis around 3. However, a steady rise in cranial capacity is observed already in Autralopithecina and does not terminate after the emergence of Homoso that it does not serve as an objective criterion to define the emergence of the genus. Homo habilis emerged about 2. Already beforethere were suggestions that H. Init was discovered that H. Instead, H. Homo erectus has often been assumed to have developed anagenetically from Homo habilis from about 2 million years ago. This scenario was strengthened with the discovery of Homo erectus georgicusearly specimens of H. As the earliest evidence for H. A separate South African species Homo gautengensis has been postulated as contemporary with Homo erectus in A taxonomy of Homo within the great apes is assessed as follows, with Paranthropus and Homo emerging within Australopithecus shown here cladistically granting ParanthropusKenyanthropusand Homo. Approximate radiation dates of daughter clades are shown in millions of years ago Mya. Note that the naming of groupings is sometimes muddled as often certain groupings are presumed before a cladistic analyses is performed. Hylobatidae gibbons. Australopithecines incl. AustralopithecusKenyanthropusParanthropusHomo. African Homo erectus s. Asian Homo erectus s. Homo sapiens. Several of the Homo lineages appear to have surviving progeny through introgression into other lines. An archaic lineage separating from the other human lineages 1.
Taxonomy and Organism Classification
Taxonomy is the science that seeks to classify and organize living things, expressed as a series of mutually exclusive categories. The highest most inclusive category is domain, of which there are three: Archea, Eubacteria, Eukaryota. Each of these domains is split into kingdoms, which are further divided until each individual organism is its own unique species. Outside of bacteria, all living things fall under the Eukaryota domain; the kingdoms are: Protista, Fungi, Plantae, and Animalia. Within each kingdom, the system classifies each organism into the hierarchical subgroups and sometimes sub-subgroups of phylum, class, order, family, genus, and species. Class Mammalia: Tetrapods with hair. Other classes of the vertebrata are Pisces fishAmphibia frogsAves birdsand Reptilia scaly things. Order Primates: Mammals with more highly developed brains, flexible hips and shoulders, and prehensile hands and feet able to grasp. Genus Homo: The human species is the only surviving species of our genus, though this genus included several species in the evolutionary past. Species Sapiens: All species are given a two-part Latin name, in which the genus name comes first and a species epithet comes second. The biologists who name species sometimes try to use a descriptor in the epithet. Taxonomy of Homo Sapiens.