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144-513: In pathology , pathogenesis is the process by which a disease or disorder develops. It can include factors which contribute not only to the onset of the disease or disorder, but also to its progression and maintenance. The word comes from Ancient Greek πάθος (pathos)  'suffering, disease' and γένεσις (genesis)  'creation'. Types of pathogenesis include microbial infection , inflammation , malignancy and tissue breakdown . For example, bacterial pathogenesis

288-408: A biopsy of nervous tissue is taken from the brain or spinal cord to aid in diagnosis. Biopsy is usually requested after a mass is detected by medical imaging . With autopsies, the principal work of the neuropathologist is to help in the post-mortem diagnosis of various conditions that affect the central nervous system. Biopsies can also consist of the skin. Epidermal nerve fiber density testing (ENFD)

432-424: A central government, a complex economy and social structure, and systems for keeping records. These cultures variously invented the wheel, mathematics, bronze-working, sailing boats, the potter's wheel , woven cloth, construction of monumental buildings, and writing. Polytheistic religions developed, centered on temples where priests and priestesses performed sacrificial rites. Writing facilitated

576-446: A combination known as general pathology. Cytopathology (sometimes referred to as "cytology") is a branch of pathology that studies and diagnoses diseases on the cellular level. It is usually used to aid in the diagnosis of cancer, but also helps in the diagnosis of certain infectious diseases and other inflammatory conditions as well as thyroid lesions, diseases involving sterile body cavities (peritoneal, pleural, and cerebrospinal), and

720-438: A conclusive diagnosis, and a skin biopsy is taken to be examined under the microscope using usual histological tests. In some cases, additional specialized testing needs to be performed on biopsies, including immunofluorescence , immunohistochemistry , electron microscopy , flow cytometry , and molecular-pathologic analysis. One of the greatest challenges of dermatopathology is its scope. More than 1500 different disorders of

864-709: A core area in Central Asia and Iran. They oversaw the Timurid Renaissance of art and architecture. Since at least the 4th century, Christianity has played a prominent role in shaping the culture, values, and institutions of Western civilization, primarily through Catholicism and later also Protestantism . Europe during the Early Middle Ages was characterized by depopulation, deurbanization , and barbarian invasions, all of which had begun in late antiquity . The barbarian invaders formed their own new kingdoms in

1008-525: A fixative that stabilizes the tissues to prevent decay. The most common fixative is formalin , although frozen section fixing is also common. To see the tissue under a microscope, the sections are stained with one or more pigments. The aim of staining is to reveal cellular components; counterstains are used to provide contrast. Histochemistry refers to the science of using chemical reactions between laboratory chemicals and components within tissue. The histological slides are then interpreted diagnostically and

1152-549: A formal area of specialty was not fully developed until the late 19th and early 20th centuries, with the advent of detailed study of microbiology . In the 19th century, physicians had begun to understand that disease-causing pathogens, or "germs" (a catch-all for disease-causing, or pathogenic, microbes, such as bacteria , viruses , fungi , amoebae , molds , protists , and prions ) existed and were capable of reproduction and multiplication, replacing earlier beliefs in humors or even spiritual agents, that had dominated for much of

1296-471: A general examination or an autopsy ). Anatomical pathology is itself divided into subfields, the main divisions being surgical pathology , cytopathology , and forensic pathology . Anatomical pathology is one of two main divisions of the medical practice of pathology, the other being clinical pathology, the diagnosis of disease through the laboratory analysis of bodily fluids and tissues. Sometimes, pathologists practice both anatomical and clinical pathology,

1440-605: A new contender that quickly surpassed both of these empires. Muhammad , the founder of Islam, initiated the early Muslim conquests in the 7th century. He established a new unified polity in Arabia that expanded rapidly under the Rashidun Caliphate and the Umayyad Caliphate , culminating in the establishment of Muslim rule on three continents (Asia, Africa, and Europe) by 750 CE. The subsequent Abbasid Caliphate oversaw

1584-437: A number of visual and microscopic tests and an especially large variety of tests of the biophysical properties of tissue samples involving automated analysers and cultures . Sometimes the general term "laboratory medicine specialist" is used to refer to those working in clinical pathology, including medical doctors, Ph.D.s and doctors of pharmacology. Immunopathology , the study of an organism's immune response to infection,

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1728-536: A pathologist generally requires specialty -training after medical school , but individual nations vary some in the medical licensing required of pathologists. In the United States, pathologists are physicians ( D.O. or M.D. ) who have completed a four-year undergraduate program, four years of medical school training, and three to four years of postgraduate training in the form of a pathology residency . Training may be within two primary specialties, as recognized by

1872-615: A political structure whereby knights and lower-status nobles owed military service to their overlords in return for the right to rents from lands and manors. Kingdoms became more centralized after the decentralizing effects of the breakup of the Carolingian Empire . In 1054, the Great Schism between the Catholic and Eastern Orthodox Churches led to the prominent cultural differences between Western and Eastern Europe. The Crusades were

2016-465: A series of empires of unprecedented size develop. Well-trained professional armies, unifying ideologies, and advanced bureaucracies created the possibility for emperors to rule over large domains whose populations could attain numbers upwards of tens of millions of subjects. International trade also expanded, most notably the massive trade routes in the Mediterranean Sea, the maritime trade web in

2160-548: A series of religious wars waged by Christians to wrest control of the Holy Land from the Muslims and succeeded for long enough to establish some Crusader states in the Levant . Italian merchants imported slaves to work in households or in sugar processing. Intellectual life was marked by scholasticism and the founding of universities, while the building of Gothic cathedrals and churches

2304-416: A significant portion of all general pathology practice is concerned with cancer , the practice of oncology makes extensive use of both anatomical and clinical pathology in diagnosis and treatment. In particular, biopsy, resection , and blood tests are all examples of pathology work that is essential for the diagnoses of many kinds of cancer and for the staging of cancerous masses . In a similar fashion,

2448-425: A suspicious lesion , whereas excisional biopsies remove the entire lesion, and are similar to therapeutic surgical resections. Excisional biopsies of skin lesions and gastrointestinal polyps are very common. The pathologist's interpretation of a biopsy is critical to establishing the diagnosis of a benign or malignant tumor, and can differentiate between different types and grades of cancer, as well as determining

2592-506: A variety of periodizations. Humans evolved in Africa from great apes through the lineage of hominins , which arose 7–5 million years ago. The ability to walk on two legs emerged after the split from chimpanzees in early hominins, such as Australopithecus , as an adaptation possibly associated with a shift from forest to savanna habitats. Hominins began to use rudimentary stone tools c.  3.3  million years ago, marking

2736-459: A vast array of species, but with a significantly smaller number of practitioners, so understanding of disease in non-human animals, especially as regards veterinary practice , varies considerably by species. Nevertheless, significant amounts of pathology research are conducted on animals, for two primary reasons: 1) The origins of diseases are typically zoonotic in nature, and many infectious pathogens have animal vectors and, as such, understanding

2880-459: A wide range of other body sites. Cytopathology is generally used on samples of free cells or tissue fragments (in contrast to histopathology, which studies whole tissues) and cytopathologic tests are sometimes called smear tests because the samples may be smeared across a glass microscope slide for subsequent staining and microscopic examination. However, cytology samples may be prepared in other ways, including cytocentrifugation . Dermatopathology

3024-418: A wide variety of diseases, including those caused by fungi , oomycetes , bacteria , viruses , viroids , virus-like organisms, phytoplasmas , protozoa , nematodes and parasitic plants . Damage caused by insects , mites , vertebrate , and other small herbivores is not considered a part of the domain of plant pathology. The field is connected to plant disease epidemiology and especially concerned with

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3168-471: A writing system and used the concept of zero in their mathematics. West of the Maya area, in central Mexico, the city of Teotihuacan prospered due to its control of the obsidian trade. Its power peaked around 450 CE, when its 125,000–150,000 inhabitants made it one of the world's largest cities. Technology developed sporadically in the ancient world. There were periods of rapid technological progress, such as

3312-496: Is a more recently developed neuropathology test in which a punch skin biopsy is taken to identify small fiber neuropathies by analyzing the nerve fibers of the skin. This test is becoming available in select labs as well as many universities; it replaces the traditional nerve biopsy test as less invasive . Pulmonary pathology is a subspecialty of anatomic (and especially surgical) pathology that deals with diagnosis and characterization of neoplastic and non-neoplastic diseases of

3456-445: Is a small piece of tissue removed primarily for surgical pathology analysis, most often in order to render a definitive diagnosis. Types of biopsies include core biopsies, which are obtained through the use of large-bore needles, sometimes under the guidance of radiological techniques such as ultrasound , CT scan , or magnetic resonance imaging . Incisional biopsies are obtained through diagnostic surgical procedures that remove part of

3600-428: Is a subspecialty of anatomic pathology that focuses on the skin and the rest of the integumentary system as an organ. It is unique, in that there are two paths a physician can take to obtain the specialization. All general pathologists and general dermatologists train in the pathology of the skin, so the term dermatopathologist denotes either of these who has reached a certain level of accreditation and experience; in

3744-404: Is also heavily, and increasingly, informed upon by neuroscience and other of the biological cognitive sciences . Mental or social disorders or behaviours seen as generally unhealthy or excessive in a given individual, to the point where they cause harm or severe disruption to the person's lifestyle, are often called "pathological" (e.g., pathological gambling or pathological liar ). Although

3888-521: Is also possible to take a Royal College of Pathologists diploma in forensic pathology, dermatopathology, or cytopathology, recognising additional specialist training and expertise and to get specialist accreditation in forensic pathology, pediatric pathology , and neuropathology. All postgraduate medical training and education in the UK is overseen by the General Medical Council. In France, pathology

4032-576: Is an example of a Neolithic religious or civic site. Metalworking was first used in the creation of copper tools and ornaments around 6400 BCE. Gold and silver soon followed, primarily for use in ornaments. The first signs of bronze , an alloy of copper and tin , date to around 4500 BCE, but the alloy did not become widely used until the third millennium BCE. The Bronze Age saw the development of cities and civilizations . Early civilizations arose close to rivers, first in Mesopotamia (3300 BCE) with

4176-411: Is considered a subfield of anatomical pathology. A physician who specializes in neuropathology, usually by completing a fellowship after a residency in anatomical or general pathology, is called a neuropathologist. In day-to-day clinical practice, a neuropathologist generates diagnoses for patients. If a disease of the nervous system is suspected, and the diagnosis cannot be made by less invasive methods,

4320-439: Is divided into a number of subdisciplines within the distinct but deeply interconnected aims of biological research and medical practice . Biomedical research into disease incorporates the work of a vast variety of life science specialists, whereas, in most parts of the world, to be licensed to practice pathology as a medical specialty, one has to complete medical school and secure a license to practice medicine. Structurally,

4464-578: Is named) having developed methods of diagnosis and prognosis for a number of diseases. The medical practices of the Romans and those of the Byzantines continued from these Greek roots, but, as with many areas of scientific inquiry, growth in understanding of medicine stagnated somewhat after the Classical Era , but continued to slowly develop throughout numerous cultures. Notably, many advances were made in

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4608-456: Is often applied in a context that is as much scientific as directly medical and encompasses the development of molecular and genetic approaches to the diagnosis and classification of human diseases, the design and validation of predictive biomarkers for treatment response and disease progression, and the susceptibility of individuals of different genetic constitution to particular disorders. The crossover between molecular pathology and epidemiology

4752-715: Is represented by a related field " molecular pathological epidemiology ". Molecular pathology is commonly used in diagnosis of cancer and infectious diseases. Molecular Pathology is primarily used to detect cancers such as melanoma, brainstem glioma, brain tumors as well as many other types of cancer and infectious diseases. Techniques are numerous but include quantitative polymerase chain reaction (qPCR), multiplex PCR , DNA microarray , in situ hybridization , DNA sequencing , antibody-based immunofluorescence tissue assays, molecular profiling of pathogens, and analysis of bacterial genes for antimicrobial resistance . Techniques used are based on analyzing samples of DNA and RNA. Pathology

4896-411: Is separated into two distinct specialties, anatomical pathology, and clinical pathology. Residencies for both lasts four years. Residency in anatomical pathology is open to physicians only, while clinical pathology is open to both physicians and pharmacists . At the end of the second year of clinical pathology residency, residents can choose between general clinical pathology and a specialization in one of

5040-427: Is sometimes considered to fall within the domain of clinical pathology. Hematopathology is the study of diseases of blood cells (including constituents such as white blood cells , red blood cells , and platelets ) and the tissues, and organs comprising the hematopoietic system. The term hematopoietic system refers to tissues and organs that produce and/or primarily host hematopoietic cells and includes bone marrow ,

5184-572: Is that the early waves of migration died out and all modern non-Africans are descended from a single group that left Africa 70,000–50,000 years ago. H. sapiens proceeded to colonize all the continents and larger islands, arriving in Australia 65,000 years ago, Europe 45,000 years ago, and the Americas 21,000 years ago. These migrations occurred during the most recent Ice Age , when various temperate regions of today were inhospitable. Nevertheless, by

5328-530: Is the best and most definitive evidence of disease (or lack thereof) in cases where tissue is surgically removed from a patient. These determinations are usually accomplished by a combination of gross (i.e., macroscopic) and histologic (i.e., microscopic) examination of the tissue, and may involve evaluations of molecular properties of the tissue by immunohistochemistry or other laboratory tests. There are two major types of specimens submitted for surgical pathology analysis: biopsies and surgical resections. A biopsy

5472-423: Is the generating of visual representations of the interior of a body for clinical analysis and medical intervention. Medical imaging reveals details of internal physiology that help medical professionals plan appropriate treatments for tissue infection and trauma. Medical imaging is also central in supplying the biometric data necessary to establish baseline features of anatomy and physiology so as to increase

5616-454: Is the process by which bacteria cause infectious illness. Most diseases are caused by multiple processes. For example, certain cancers arise from dysfunction of the immune system ( skin tumors and lymphoma after a renal transplant , which requires immunosuppression ), Streptococcus pneumoniae is spread through contact with respiratory secretions , such as saliva , mucus , or cough droplets from an infected person and colonizes

5760-499: Is to classify mental illness, elucidate its underlying causes, and guide clinical psychiatric treatment accordingly. Although diagnosis and classification of mental norms and disorders is largely the purview of psychiatry—the results of which are guidelines such as the Diagnostic and Statistical Manual of Mental Disorders , which attempt to classify mental disease mostly on behavioural evidence, though not without controversy —the field

5904-597: Is widely used for gene therapy and disease diagnosis. Oral and Maxillofacial Pathology is one of nine dental specialties recognized by the American Dental Association , and is sometimes considered a specialty of both dentistry and pathology. Oral Pathologists must complete three years of post doctoral training in an accredited program and subsequently obtain diplomate status from the American Board of Oral and Maxillofacial Pathology. The specialty focuses on

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6048-488: The Ancient Greek roots pathos ( πάθος ), meaning "experience" or "suffering", and -logia ( -λογία ), meaning "study of". The term is of early 16th-century origin, and became increasingly popularized after the 1530s. The study of pathology, including the detailed examination of the body, including dissection and inquiry into specific maladies, dates back to antiquity. Rudimentary understanding of many conditions

6192-691: The Athenian Empire (454–404 BCE), which was defeated by a Spartan-led coalition during the Peloponnesian War . Philip of Macedon unified the Greek city-states into the Hellenic League and his son Alexander the Great (356–323 BCE) founded an empire extending from present-day Greece to India. The empire divided into several successor states shortly after his death, resulting in the founding of many cities and

6336-576: The Axial Age . The following post-classical period , from about 500 to 1500 CE, witnessed the rise of Islam and the continued spread and consolidation of Christianity while civilization expanded to new parts of the world and trade between societies increased. These developments were accompanied by the rise and decline of major empires, such as the Byzantine Empire , the Islamic Caliphates ,

6480-1012: The Ayyubids in the 12th century, and them later by the Mamluks in the 13th century. In the Maghreb and Western Sahara , the Almoravids dominated from the 11th century, until it was subsumed by the Almohad Caliphate in the 12th century. The Almohad's collapse gave rise to the Marinids in Morocco, the Zayyanids in Algeria, and the Hafsids in Tunisia. In Nubia the Kingdom of Kush

6624-627: The Earth by the end of the Ice Age 12,000 years ago. Soon afterward, the Neolithic Revolution in West Asia brought the first systematic husbandry of plants and animals, and saw many humans transition from a nomadic life to a sedentary existence as farmers in permanent settlements . The growing complexity of human societies necessitated systems of accounting and writing . These developments paved

6768-686: The Eastern Agricultural Complex . They built earthworks such as Watson Brake (4000 BCE) and Poverty Point (3600 BCE), both in Louisiana. From 800 to 200 BCE, the Axial Age saw the emergence of transformative philosophical and religious ideas that developed in many different places mostly independently of each other. Chinese Confucianism , Indian Buddhism and Jainism , and Jewish monotheism all arose during this period. Persian Zoroastrianism began earlier, perhaps around 1000 BCE, but

6912-652: The Indus script . In China, writing was first used during the Shang dynasty (1766–1045 BCE). Transport was facilitated by waterways, including rivers and seas, which fostered the projection of military power and the exchange of goods, ideas, and inventions. The Bronze Age also saw new land technologies, such as horse-based cavalry and chariots , that allowed armies to move faster. Trade became increasingly important as urban societies exchanged manufactured goods for raw materials from distant lands, creating vast commercial networks and

7056-828: The Late Bronze Age collapse that affected many Mediterranean civilizations between 1300 and 1000 BCE. The foundations of many cultural aspects in India were laid in the Vedic period (1750–600 BCE), including the emergence of Hinduism . From around 550 BCE, many independent kingdoms and republics known as the Mahajanapadas were established across the subcontinent. Speakers of the Bantu languages began expanding across Central, Eastern, and Southern Africa as early as 3000 BCE until 1000 CE. Their expansion and encounters with other groups resulted in

7200-550: The Mongol Empire , and various Chinese dynasties . This period's invention of gunpowder and of the printing press greatly affected subsequent history. During the early modern period , spanning from approximately 1500 to 1800 CE, European powers explored and colonized regions worldwide, intensifying cultural and economic exchange. This era saw substantial intellectual, cultural, and technological advances in Europe driven by

7344-701: The Qin dynasty (221–206 BCE). Qin Shi Huang was an adherent of the Legalist school of thought and he displaced the hereditary aristocracy by creating an efficient system of administration staffed by officials appointed according to merit. The harshness of the Qin dynasty led to rebellions and the dynasty's fall. It was followed by the Han dynasty (202 BCE–220 CE), which combined the Legalist bureaucratic system with Confucian ideals. The Han dynasty

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7488-712: The Renaissance , the Scientific Revolution , and the Enlightenment . By the 18th century, the accumulation of knowledge and technology had reached a critical mass that brought about the Industrial Revolution , substantial to the Great Divergence , and began the modern period starting around 1800 CE. The rapid growth in productive power further increased international trade and colonization , linking

7632-596: The Sui dynasty (581–618). The Chinese were confronted by Turkic nomads, who were becoming the most dominant ethnic group in the region. Originally the relationship was largely cooperative but in 630, the Tang dynasty began an offensive against the Turks by capturing areas of the Ordos Desert . In the 8th century, Islam began to penetrate the region and soon became the sole faith of most of

7776-811: The Tigris and Euphrates , followed by the Egyptian civilization along the Nile River (3200 BCE), the Norte Chico civilization in coastal Peru (3100 BCE), the Indus Valley civilization in Pakistan and northwestern India (2500 BCE), and the Chinese civilization along the Yangtze and Yellow Rivers (2200 BCE). These societies developed a number of shared characteristics, including

7920-684: The Yellow River Valley may have cultivated millet by 7000 BCE. Pigs were the most important domesticated animal in early China. People in Africa's Sahara cultivated sorghum and several other crops between 8000 and 5000 BCE, while other agricultural centers arose in the Ethiopian Highlands and the West African rainforests. In the Indus River Valley , crops were cultivated by 7000 BCE and cattle were domesticated by 6500 BCE. In

8064-485: The compass , one of China's Four Great Inventions . In Africa, the Kingdom of Kush prospered through its interactions with both Egypt and sub-Saharan Africa. It ruled Egypt as the Twenty-fifth Dynasty from 712 to 650 BCE, then continued as an agricultural and trading state based in the city of Meroë until the fourth century CE. The Kingdom of Aksum , centered in present-day Ethiopia, established itself by

8208-765: The early Muslim conquests , the Islamic Golden Age , and the commencement and expansion of the Arab slave trade , followed by the Mongol invasions and the founding of the Ottoman Empire. South Asia had a series of middle kingdoms , followed by the establishment of Islamic empires in India. In West Africa, the Mali and Songhai Empires rose. On the southeast coast of Africa, Arabic ports were established where gold, spices , and other commodities were traded. This allowed Africa to join

8352-502: The horticulture of species that are of high importance to the human diet or other human utility. Historical era Human history is the record of humankind from prehistory to the present . Modern humans evolved in Africa around 300,000 years ago and initially lived as hunter-gatherers . They migrated out of Africa during the Last Ice Age and had populated most of

8496-569: The interdisciplinary field of molecular pathological epidemiology . Molecular pathological epidemiology can help to assess pathogenesis and causality by means of linking a potential risk factor to molecular pathologic signatures of a disease. Thus, the molecular pathological epidemiology paradigm can advance the area of causal inference . Pathology As a field of general inquiry and research, pathology addresses components of disease: cause, mechanisms of development ( pathogenesis ), structural alterations of cells (morphologic changes), and

8640-409: The kidneys . In a medical setting, renal pathologists work closely with nephrologists and transplant surgeons , who typically obtain diagnostic specimens via percutaneous renal biopsy. The renal pathologist must synthesize findings from traditional microscope histology, electron microscopy , and immunofluorescence to obtain a definitive diagnosis. Medical renal diseases may affect the glomerulus ,

8784-416: The lungs and thoracic pleura . Diagnostic specimens are often obtained via bronchoscopic transbronchial biopsy, CT -guided percutaneous biopsy, or video-assisted thoracic surgery . These tests can be necessary to diagnose between infection, inflammation , or fibrotic conditions. Renal pathology is a subspecialty of anatomic pathology that deals with the diagnosis and characterization of disease of

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8928-488: The lymph nodes , thymus , spleen , and other lymphoid tissues. In the United States, hematopathology is a board certified subspecialty (licensed under the American Board of Pathology) practiced by those physicians who have completed a general pathology residency (anatomic, clinical, or combined) and an additional year of fellowship training in hematology. The hematopathologist reviews biopsies of lymph nodes, bone marrows and other tissues involved by an infiltrate of cells of

9072-546: The sack of Constantinople in 1204. In the early 13th century, a new wave of invaders, the Mongols , swept through the region but were eventually eclipsed by the Turks and the founding of the Ottoman Empire in modern-day Turkey around 1299. Steppe nomads from Central Asia continued to threaten sedentary societies in the post-classical era, but they also faced incursions from the Arabs and Chinese. China expanded into Central Asia during

9216-505: The stirrup (India, 2nd century BCE and Central Asia, 1st century CE), both of which diffused widely throughout the world. The Chinese learned to make silk and built massive engineering projects such as the Great Wall of China and the Grand Canal . The Romans were also accomplished builders, inventing concrete , perfecting the use of arches in construction, and creating aqueducts to transport water over long distances to urban centers. Most ancient societies practiced slavery , which

9360-475: The tubules and interstitium , the vessels, or a combination of these compartments. Surgical pathology is one of the primary areas of practice for most anatomical pathologists. Surgical pathology involves the gross and microscopic examination of surgical specimens, as well as biopsies submitted by surgeons and non-surgeons such as general internists , medical subspecialists , dermatologists , and interventional radiologists . Often an excised tissue sample

9504-499: The 10th and 9th millennia BCE. Pastoral societies based on nomadic animal herding also developed, mostly in dry areas unsuited for plant cultivation such as the Eurasian Steppe or the African Sahel . Conflict between nomadic herders and sedentary agriculturalists was frequent and became a recurring theme in world history. Neolithic societies usually worshiped ancestors, sacred places, or anthropomorphic deities . The vast complex of Göbekli Tepe in Turkey, dated 9500–8000 BCE,

9648-488: The 17th century, the study of rudimentary microscopy was underway and examination of tissues had led British Royal Society member Robert Hooke to coin the word " cell ", setting the stage for later germ theory . Modern pathology began to develop as a distinct field of inquiry during the 19th Century through natural philosophers and physicians that studied disease and the informal study of what they termed "pathological anatomy" or "morbid anatomy". However, pathology as

9792-418: The 1st century CE as a major trading empire, dominating its neighbors in South Arabia and Kush and controlling the Red Sea trade. It minted its own currency and carved enormous monolithic stelae to mark its emperors' graves. Successful regional empires were also established in the Americas, arising from cultures established as early as 2500 BCE. In Mesoamerica, vast pre-Columbian societies were built,

9936-409: The 7th century CE. Buddhism became the main religion in much of South, Southeast, and East Asia. The Greek philosophical tradition diffused throughout the Mediterranean world and as far as India, starting in the 4th century BCE after the conquests of Alexander the Great of Macedon . Both Christianity and Islam developed from the beliefs of Judaism . The millennium from 500 BCE to 500 CE saw

10080-420: The 9th century, when it succumbed to pressure from new invaders—the Vikings , Magyars , and Arabs. During the Carolingian era, churches developed a form of musical notation called neume which became the basis for the modern notation system. Kievan Rus' expanded from its capital in Kiev to become the largest state in Europe by the 10th century. In 988, Vladimir the Great adopted Orthodox Christianity as

10224-534: The American Board of Pathology: [anatomical pathology and clinical pathology, each of which requires separate board certification. The American Osteopathic Board of Pathology also recognizes four primary specialties: anatomic pathology, dermatopathology, forensic pathology, and laboratory medicine . Pathologists may pursue specialised fellowship training within one or more subspecialties of either anatomical or clinical pathology. Some of these subspecialties permit additional board certification, while others do not. In

10368-759: The Americas, squash was cultivated by at least 8500 BCE in South America, and domesticated arrowroot appeared in Central America by 7800 BCE. Potatoes were first cultivated in the Andes of South America, where the llama was also domesticated. It is likely that women played a central role in plant domestication throughout these developments. Various explanations of the causes of the Neolithic Revolution have been proposed. Some theories identify population growth as

10512-731: The Greco-Roman era in the Mediterranean region. Greek science , technology , and mathematics are generally considered to have reached their peak during the Hellenistic period, typified by devices such as the Antikythera mechanism . There were also periods of technological decay, such as the Roman Empire's decline and fall and the ensuing early medieval period. Two of the most important innovations were paper (China, 1st and 2nd centuries CE) and

10656-829: The Indian Ocean , and the Silk Road . The kingdom of the Medes helped to destroy the Assyrian Empire in tandem with the nomadic Scythians and the Babylonians . Nineveh , the capital of Assyria, was sacked by the Medes in 612 BCE. The Median Empire gave way to successive Iranian states, including the Achaemenid (550–330 BCE), Parthian (247 BCE–224 CE), and Sasanian Empires (224–651 CE). Two major empires began in modern-day Greece . In

10800-766: The Islamic Golden Age, an era of learning, science, and invention during which philosophy , art , and literature flourished. Scholars preserved and synthesized knowledge and skills of ancient Greece and Persia the manufacture of paper from China and the decimal positional numbering system from India. At the same time, they made significant original contributions in various fields, such as Al-Khwarizmi 's development of algebra and Avicenna 's comprehensive philosophical system. Islamic civilization expanded both by conquest and based on its merchant economy. Merchants brought goods and their Islamic faith to China , India , Southeast Asia , and Africa . Arab domination of

10944-603: The Mediterranean-European world, political unity was always eventually restored. After the fall of the Eastern Han dynasty and the demise of the Three Kingdoms, nomadic tribes from the north began to invade, causing many Chinese people to flee southward. The post-classical period, dated roughly from 500 to 1500 CE, was characterized by the rise and spread of major religions while civilization expanded to new parts of

11088-722: The Middle East ended in the mid-11th century with the arrival of the Seljuk Turks , migrating south from the Turkic homelands. The Seljuks were challenged by Europe during the Crusades , a series of religious wars aimed at rolling back Muslim territory and regaining control of the Holy Land . The Crusades were ultimately unsuccessful and served more to weaken the Byzantine Empire, especially with

11232-643: The Norte Chico culture emerged in Peru around 3100 BCE. The Norte Chico built public monumental architecture at the city of Caral , dated 2627–1977 BCE. The later Chavín polity is sometimes described as the first Andean state, centered on the religious site at Chavín de Huantar . Other important Andean cultures include the Moche , whose ceramics depict many aspects of daily life, and the Nazca , who created animal-shaped designs in

11376-509: The Romans. The Republic became an empire and by the time of Augustus (63 BCE–14 CE), it had established dominion over most of the Mediterranean Sea. The empire continued to grow and reached its peak under Trajan (53–117 CE), controlling much of the land from England to Mesopotamia. The two centuries that followed are known as the Pax Romana , a period of unprecedented peace, prosperity, and political stability in most of Europe. Christianity

11520-613: The Southeast Asia trading system, bringing it contact with Asia; this resulted in the Swahili culture . China experienced the relatively successive Sui, Tang, Song , Yuan , and early Ming dynasties . Middle Eastern trade routes along the Indian Ocean, and the Silk Road through the Gobi Desert , provided limited economic and cultural contact between Asian and European civilizations. During

11664-484: The US, either a general pathologist or a dermatologist can undergo a 1 to 2 year fellowship in the field of dermatopathology. The completion of this fellowship allows one to take a subspecialty board examination, and becomes a board certified dermatopathologist. Dermatologists are able to recognize most skin diseases based on their appearances, anatomic distributions, and behavior. Sometimes, however, those criteria do not lead to

11808-671: The United Kingdom, pathologists are physicians licensed by the UK General Medical Council . The training to become a pathologist is under the oversight of the Royal College of Pathologists . After four to six years of undergraduate medical study, trainees proceed to a two-year foundation program. Full-time training in histopathology currently lasts between five and five and a half years and includes specialist training in surgical pathology, cytopathology, and autopsy pathology. It

11952-429: The accuracy with which early or fine-detail abnormalities are detected. These diagnostic techniques are often performed in combination with general pathology procedures and are themselves often essential to developing new understanding of the pathogenesis of a given disease and tracking the progress of disease in specific medical cases. Examples of important subdivisions in medical imaging include radiology (which uses

12096-429: The activity of specific molecular pathways in the tumor. Surgical resection specimens are obtained by the therapeutic surgical removal of an entire diseased area or organ (and occasionally multiple organs). These procedures are often intended as definitive surgical treatment of a disease in which the diagnosis is already known or strongly suspected, but pathological analysis of these specimens remains important in confirming

12240-606: The administration of cities, the expression of ideas, and the preservation of information. It may have independently developed in at least four ancient civilizations: Mesopotamia (3300 BCE), Egypt (around 3250 BCE), China (1200 BCE), and lowland Mesoamerica (by 650 BCE). The earliest system of writing was the Mesopotamian cuneiform script , which began as a system of pictographs , whose pictorial representations eventually became simplified and more abstract. Other influential early writing systems include Egyptian hieroglyphs and

12384-501: The advent of the Paleolithic era. The genus Homo evolved from Australopithecus . The earliest record of Homo is the 2.8 million-year-old specimen LD 350-1 from Ethiopia, and the earliest named species is Homo habilis which evolved by 2.3 million years ago. The most important difference between Homo habilis and Australopithecus was a 50% increase in brain size. H. erectus evolved about 2 million years ago and

12528-423: The basis of the involved sample types (comparing, for example, cytopathology , hematopathology , and histopathology ), organs (as in renal pathology ), and physiological systems ( oral pathology ), as well as on the basis of the focus of the examination (as with forensic pathology ). Pathology is a significant field in modern medical diagnosis and medical research . The Latin term pathology derives from

12672-600: The beginnings of archaic globalization . Bronze production in Southwest Asia, for example, required the import of tin from as far away as England. The growth of cities was often followed by the establishment of states and empires. In Egypt, the initial division into Upper and Lower Egypt was followed by the unification of the whole valley around 3100 BCE. Around 2600 BCE, the Indus Valley civilization built major cities at Harappa and Mohenjo-daro . Mesopotamian history

12816-399: The consequences of changes (clinical manifestations). In common medical practice, general pathology is mostly concerned with analyzing known clinical abnormalities that are markers or precursors for both infectious and non-infectious disease, and is conducted by experts in one of two major specialties, anatomical pathology and clinical pathology . Further divisions in specialty exist on

12960-410: The creation of the first cities and states . Cities were centers of trade , manufacturing , and political power . They developed mutually beneficial relationships with their surrounding countrysides , receiving agricultural products and providing manufactured goods and varying degrees of political control in return. Early proto-cities appeared at Çatalhöyük and Jericho , possibly as early as

13104-557: The desert called Nazca lines . The Olmecs of Mesoamerica developed by about 1200 BCE and are known for the colossal stone heads that they carved from basalt . They also devised the Mesoamerican calendar that was used by later cultures such as the Maya and Teotihuacan . Societies in North America were primarily egalitarian hunter-gatherers, supplementing their diet with the plants of

13248-525: The diagnosis, clinical management and investigation of diseases that affect the oral cavity and surrounding maxillofacial structures including but not limited to odontogenic , infectious, epithelial , salivary gland , bone and soft tissue pathologies. It also significantly intersects with the field of dental pathology . Although concerned with a broad variety of diseases of the oral cavity, they have roles distinct from otorhinolaryngologists ("ear, nose, and throat" specialists), and speech pathologists ,

13392-683: The different civilizations in the process of globalization , and cemented European dominance throughout the 19th century. Over the last quarter-millennium, despite the devastating effects of two world wars , there has been a great acceleration in the rates of growth of many domains, including human population , agriculture, industry, commerce, scientific knowledge, technology, communications, military capabilities, and environmental degradation . The study of human history relies on insights from academic disciplines including history , archaeology , anthropology , linguistics , and genetics . To provide an accessible overview, researchers divide human history by

13536-442: The disciplines, but they can not practice anatomical pathology, nor can anatomical pathology residents practice clinical pathology. Though separate fields in terms of medical practice, a number of areas of inquiry in medicine and medical science either overlap greatly with general pathology, work in tandem with it, or contribute significantly to the understanding of the pathology of a given disease or its course in an individual. As

13680-559: The displacement of the Pygmy peoples and the Khoisan , and in the spread of mixed farming and ironworking throughout sub-Saharan Africa, laying the foundations for later states. The Lapita culture emerged in the Bismarck Archipelago near New Guinea around 1500 BCE and colonized many uninhabited islands of Remote Oceania , reaching as far as Samoa by 700 BCE. In the Americas,

13824-548: The end of the Ice Age some 12,000 years ago, humans had colonized nearly all ice-free parts of the globe. Human expansion coincided with both the Quaternary extinction event and the Neanderthal extinction . These extinctions were probably caused by climate change, human activity, or a combination of the two. Beginning around 10,000 BCE, the Neolithic Revolution marked the development of agriculture , which fundamentally changed

13968-420: The examination of a biopsy or surgical specimen by a pathologist, after the specimen has been processed and histological sections have been placed onto glass slides. This contrasts with the methods of cytopathology, which uses free cells or tissue fragments. Histopathological examination of tissues starts with surgery , biopsy , or autopsy. The tissue is removed from the body of an organism and then placed in

14112-623: The frontiers hastened internal dissolution. The Han dynasty fell into civil war in 220 CE, beginning the Three Kingdoms period, while its Roman counterpart became increasingly decentralized and divided about the same time in what is known as the Crisis of the Third Century . From the Eurasian Steppe, horse-based nomads dominated a large part of the continent. The development of the stirrup and

14256-504: The hematopoietic system. In addition, the hematopathologist may be in charge of flow cytometric and/or molecular hematopathology studies. Molecular pathology is focused upon the study and diagnosis of disease through the examination of molecules within organs, tissues or bodily fluids . Molecular pathology is multidisciplinary by nature and shares some aspects of practice with both anatomic pathology and clinical pathology, molecular biology , biochemistry , proteomics and genetics . It

14400-743: The human ability to communicate. Signs of early artistic expression can be found in the form of cave paintings and sculptures made from ivory, stone, and bone, implying a form of spirituality generally interpreted as animism or shamanism . The earliest known musical instruments besides the human voice are bone flutes from the Swabian Jura in Germany, dated around 40,000 years old. Paleolithic humans lived as hunter-gatherers and were generally nomadic . The migration of anatomically modern humans out of Africa took place in multiple waves beginning 194,000–177,000 years ago. The dominant view among scholars

14544-425: The human host. To determine causes of diseases, medical experts used the most common and widely accepted assumptions or symptoms of their times, a general principle of approach that persists in modern medicine. Modern medicine was particularly advanced by further developments of the microscope to analyze tissues, to which Rudolf Virchow gave a significant contribution, leading to a slew of research developments. By

14688-505: The human lifestyle. Agriculture began independently in different parts of the globe, and included a diverse range of taxa , in at least 11 separate centers of origin . Cereal crop cultivation and animal domestication had occurred in Mesopotamia by at least 8500 BCE in the form of wheat, barley , sheep, and goats. The Yangtze River Valley in China domesticated rice around 8000–7000 BCE;

14832-431: The identity of a corpse. The requirements for becoming a licensed practitioner of forensic pathology varies from country to country (and even within a given nation ) but typically a minimal requirement is a medical doctorate with a specialty in general or anatomical pathology with subsequent study in forensic medicine. The methods forensic scientists use to determine death include examination of tissue specimens to identify

14976-490: The imaging technologies of X-ray radiography ) magnetic resonance imaging , medical ultrasonography (or ultrasound), endoscopy , elastography , tactile imaging , thermography , medical photography , nuclear medicine and functional imaging techniques such as positron emission tomography . Though they do not strictly relay images, readings from diagnostics tests involving electroencephalography , magnetoencephalography , and electrocardiography often give hints as to

15120-435: The largest body of research in veterinary pathology. Animal testing remains a controversial practice, even in cases where it is used to research treatment for human disease. As in human medical pathology, the practice of veterinary pathology is customarily divided into the two main fields of anatomical and clinical pathology. Although the pathogens and their mechanics differ greatly from those of animals, plants are subject to

15264-674: The late 1340s, and killed tens of millions of Europeans in six years; between a quarter and a third of the population perished. Africa was home to many different civilizations. In the 7th century North Africa saw the extinguishment of Byzantine Africa and the Berber kingdoms in the Early Muslim conquests . From the 10th century the Arabian empire's African territory was consumed by the Fatimid Caliphate centred on Egypt, who were supplanted by

15408-478: The late 14th century formed a personal union with Poland . The Late Middle Ages were marked by difficulties and calamities. Famine, plague, and war devastated the population of Western Europe. The Black Death alone killed approximately 75 to 200 million people between 1347 and 1350. It was one of the deadliest pandemics in human history. Starting in Asia, the disease reached the Mediterranean and Western Europe during

15552-431: The late 1920s to early 1930s pathology was deemed a medical specialty. Combined with developments in the understanding of general physiology , by the beginning of the 20th century, the study of pathology had begun to split into a number of distinct fields, resulting in the development of a large number of modern specialties within pathology and related disciplines of diagnostic medicine . The modern practice of pathology

15696-655: The late 5th century BCE, several Greek city states checked the Achaemenid Persian advance in Europe through the Greco-Persian Wars . These wars were followed by the Golden Age of Athens , the seminal period of ancient Greece that laid many of the foundations of Western civilization , including the first theatrical performances . The wars led to the creation of the Delian League , founded in 477 BCE, and eventually

15840-435: The latter of which helps diagnose many neurological or neuromuscular conditions relevant to speech phonology or swallowing . Owing to the availability of the oral cavity to non-invasive examination, many conditions in the study of oral disease can be diagnosed, or at least suspected, from gross examination, but biopsies, cell smears, and other tissue analysis remain important diagnostic tools in oral pathology. Becoming

15984-416: The main factor, leading people to seek out new food sources. Others see population growth not as the cause but as the effect of the associated improvements in food supply. Further suggested factors include climate change, resource scarcity, and ideology. The transition to agriculture created food surpluses that could support people not directly engaged in food production, permitting far denser populations and

16128-448: The mechanisms of action for these pathogens in non-human hosts is essential to the understanding and application of epidemiology and 2) those animals that share physiological and genetic traits with humans can be used as surrogates for the study of the disease and potential treatments as well as the effects of various synthetic products. For this reason, as well as their roles as livestock and companion animals , mammals generally have

16272-440: The medieval era of Islam (see Medicine in medieval Islam ), during which numerous texts of complex pathologies were developed, also based on the Greek tradition. Even so, growth in complex understanding of disease mostly languished until knowledge and experimentation again began to proliferate in the Renaissance , Enlightenment , and Baroque eras, following the resurgence of the empirical method at new centers of scholarship. By

16416-563: The most notable being the Zapotec civilization (700 BCE–1521 CE), and the Maya civilization, which reached its highest state of development during the Mesoamerican classic period (c. 250–900 CE), but continued throughout the post-classic period. The great Maya city-states slowly rose in number and prominence, and Maya culture spread throughout the Yucatán and surrounding areas. The Maya developed

16560-491: The period referred to as ancient India's golden age. The resulting stability helped usher in a flourishing period for Hindu and Buddhist culture in the 4th and 5th centuries, as well as major advances in science and mathematics. In South India , three prominent Dravidian kingdoms emerged: the Cheras , Cholas , and Pandyas . In China, Qin Shi Huang put an end to the chaotic Warring States period by uniting all of China under

16704-708: The population, though Buddhism remained strong in the east. From the 9th to 13th centuries, Central Asia was divided among several powerful states, including the Samanid , Seljuk , and Khwarazmian Empires . These states were succeeded by the Mongols in the 13th century. In 1370, Timur , a Turkic leader in the Mongol military tradition, conquered most of the region and founded the Timurid Empire . Timur's large empire collapsed soon after his death, but his descendants retained control of

16848-518: The presence or absence of natural disease and other microscopic findings, interpretations of toxicology on body tissues and fluids to determine the chemical cause of overdoses, poisonings or other cases involving toxic agents, and examinations of physical trauma . Forensic pathology is a major component in the trans-disciplinary field of forensic science . Histopathology refers to the microscopic examination of various forms of human tissue . Specifically, in clinical medicine, histopathology refers to

16992-472: The previous 1,500 years in European medicine. With the new understanding of causative agents, physicians began to compare the characteristics of one germ's symptoms as they developed within an affected individual to another germ's characteristics and symptoms. This approach led to the foundational understanding that diseases are able to replicate themselves, and that they can have many profound and varied effects on

17136-485: The previous diagnosis. Clinical pathology is a medical specialty that is concerned with the diagnosis of disease based on the laboratory analysis of bodily fluids such as blood and urine , as well as tissues, using the tools of chemistry , clinical microbiology , hematology and molecular pathology. Clinical pathologists work in close collaboration with medical technologists , hospital administrations, and referring physicians. Clinical pathologists learn to administer

17280-626: The remains of the Western Roman Empire. Although there were substantial changes in society and political structures, most of the new kingdoms incorporated existing Roman institutions. Christianity expanded in Western Europe, and monasteries were founded. In the 7th and 8th centuries, the Franks under the Carolingian dynasty established an empire covering much of Western Europe; it lasted until

17424-508: The resulting pathology report describes the histological findings and the opinion of the pathologist. In the case of cancer, this represents the tissue diagnosis required for most treatment protocols. Neuropathology is the study of disease of nervous system tissue, usually in the form of either surgical biopsies or sometimes whole brains in the case of autopsy. Neuropathology is a subspecialty of anatomic pathology, neurology , and neurosurgery . In many English-speaking countries, neuropathology

17568-581: The same period, civilizations in the Americas, such as the Mississippians , Aztecs , Maya, and Inca reached their zenith. Before the advent of Islam in the 7th century, the Middle East was dominated by the Byzantine and Sasanian Empires, which frequently fought each other for control of several disputed regions. This was also a cultural battle, with Byzantine Christian culture competing against Persian Zoroastrian traditions. The birth of Islam created

17712-602: The skin exist, including cutaneous eruptions (" rashes ") and neoplasms . Therefore, dermatopathologists must maintain a broad base of knowledge in clinical dermatology, and be familiar with several other specialty areas in Medicine. Forensic pathology focuses on determining the cause of death by post-mortem examination of a corpse or partial remains. An autopsy is typically performed by a coroner or medical examiner, often during criminal investigations; in this role, coroners and medical examiners are also frequently asked to confirm

17856-410: The species Homo heidelbergensis . Humans continued to develop over the succeeding millennia, and by 100,000 years ago, were using jewelry and ocher to adorn the body. By 50,000 years ago, they buried their dead, used projectile weapons, and engaged in seafaring. One of the most important changes (the date of which is unknown) was the development of syntactic language , which dramatically improved

18000-573: The spread of Greek culture throughout conquered regions, a process referred to as Hellenization . The Hellenistic period lasted from the death of Alexander in 323 BCE to 31 BCE when Ptolemaic Egypt fell to Rome. In Europe, the Roman Republic was founded in the 6th century BCE and began expanding its territory in the 3rd century BCE. Priorly, the Carthaginian Empire had dominated the Mediterranean, however lost three successive wars to

18144-517: The state and function of certain tissues in the brain and heart respectively. Pathology informatics is a subfield of health informatics . It is the use of information technology in pathology. It encompasses pathology laboratory operations, data analysis, and the interpretation of pathology-related information. Key aspects of pathology informatics include: Psychopathology is the study of mental illness , particularly of severe disorders. Informed heavily by both psychology and neurology , its purpose

18288-489: The state religion. During the High Middle Ages , which began after 1000, the population of Europe increased as technological and agricultural innovations allowed trade to flourish and crop yields to increase. The establishment of the feudal system affected the structure of medieval society. It included manorialism , the organization of peasants into villages that owed rents and labor service to nobles, and vassalage ,

18432-474: The study of disease is divided into many different fields that study or diagnose markers for disease using methods and technologies particular to specific scales, organs , and tissue types. Anatomical pathology ( Commonwealth ) or anatomic pathology ( United States ) is a medical specialty that is concerned with the diagnosis of disease based on the gross , microscopic , chemical, immunologic and molecular examination of organs, tissues, and whole bodies (as in

18576-452: The tissue and blood analysis techniques of general pathology are of central significance to the investigation of serious infectious disease and as such inform significantly upon the fields of epidemiology , etiology , immunology , and parasitology . General pathology methods are of great importance to biomedical research into disease, wherein they are sometimes referred to as "experimental" or "investigative" pathology . Medical imaging

18720-456: The upper respiratory tract and begins to multiply. The pathogenic mechanisms of a disease (or condition) are set in motion by the underlying causes, which if controlled would allow the disease to be prevented . Often, a potential cause is identified by epidemiological observations before a pathological link can be drawn between the cause and the disease. The pathological perspective can be directly integrated into an epidemiological approach in

18864-432: The use of horse archers made the nomads a constant threat to sedentary civilizations. In the 4th century CE, the Roman Empire split into western and eastern regions, with usually separate emperors. The Western Roman Empire fell in 476 CE to German influence under Odoacer . The Eastern Roman Empire, known as the Byzantine Empire , was more long-lasting. In China, dynasties rose and fell, but, in sharp contrast to

19008-474: The vast majority of lab work and research in pathology concerns the development of disease in humans, pathology is of significance throughout the biological sciences. Two main catch-all fields exist to represent most complex organisms capable of serving as host to a pathogen or other form of disease: veterinary pathology (concerned with all non-human species of kingdom of Animalia ) and phytopathology , which studies disease in plants. Veterinary pathology covers

19152-553: The way for the emergence of early civilizations in Mesopotamia , Egypt , the Indus Valley , and China , marking the beginning of the Ancient period in 3500 BCE. These civilizations supported the establishment of regional empires and acted as a fertile ground for the advent of transformative philosophical and religious ideas, initially Hinduism during the late Bronze Age , and later Buddhism , Confucianism , Greek philosophy , Jainism , Judaism , Taoism , and Zoroastrianism during

19296-622: The world and trade between societies intensified. From the 10th to 13th centuries, the Medieval Warm Period in the northern hemisphere aided agriculture and led to population growth in parts of Europe and Asia. It was followed by the Little Ice Age , which, along with the plagues of the 14th century, put downward pressure on the population of Eurasia. Major inventions of the period were gunpowder , guns, and printing, all of which originated in China. The post-classical period encompasses

19440-522: Was legalized by Constantine I in 313 CE after three centuries of imperial persecution . It became the sole official religion of the empire in 380 CE while the emperor Theodosius outlawed pagan religions in 391–392 CE. In South Asia, Chandragupta Maurya founded the Maurya Empire (320–185 BCE), which flourished under Ashoka the Great . From the 4th to 6th centuries CE, the Gupta Empire oversaw

19584-573: Was characterized by frequent wars between city-states, leading to shifts in hegemony from one city to another. In the 25th–21st centuries BCE, the empires of Akkad and the Neo-Sumerians arose in this area. In Crete, the Minoan civilization emerged by 2000 BCE and is regarded as the first civilization in Europe. Over the following millennia, civilizations developed across the world. By 1600 BCE, Mycenaean Greece began to develop. It flourished until

19728-464: Was comparable in power and influence to the Roman Empire that lay at the other end of the Silk Road. As economic prosperity fueled their military expansion, the Han conquered parts of Mongolia, Central Asia, Manchuria , Korea, and northern Vietnam. As with other empires during the classical period, Han China advanced significantly in the areas of government, education, science, and technology. The Han invented

19872-629: Was institutionalized by the Achaemenid Empire during the Axial Age. New philosophies took hold in Greece during the 5th century BCE, epitomized by thinkers such as Plato and Aristotle . The first Olympic Games were held in 776 BCE, marking a period known as " classical antiquity ". In 508 BCE, the world's first democratic system of government was instituted in Athens . Axial Age ideas shaped subsequent intellectual and religious history. Confucianism

20016-561: Was not a simple linear or branched progression but involved interbreeding between related species . Genomic research has shown that hybridization between substantially diverged lineages was common in human evolution. DNA evidence suggests that several genes of Neanderthal origin are present among all non- sub-Saharan African populations. Neanderthals and other hominins, such as Denisovans, may have contributed up to 6% of their genome to present-day non-sub-Saharan African humans. Homo sapiens emerged in Africa around 300,000 years ago from

20160-432: Was one of the outstanding artistic achievements of the age. The Middle Ages witnessed the first sustained urbanization of Northern and Western Europe and lasted until the beginning of the early modern period in the 16th century. The Mongols reached Europe in 1236 and conquered Kievan Rus' , along with briefly invading Poland and Hungary . Lithuania cooperated with the Mongols but remained independent and in

20304-468: Was one of the three schools of thought that came to dominate Chinese thinking, along with Taoism and Legalism . The Confucian tradition, which would become particularly influential, looked for political morality not to the force of law but to the power and example of tradition. Confucianism would later spread to Korea and Japan. Buddhism reached China in about the 1st century CE and spread widely, with 30,000 Buddhist temples in northern China alone by

20448-449: Was particularly prevalent in Athens and Rome , where slaves made up a large proportion of the population and were foundational to the economy. Patriarchy was also common, with men controlling more political and economic power than women. The ancient empires faced common problems associated with maintaining huge armies and supporting a central bureaucracy . In Rome and Han China, the state began to decline, and barbarian pressure on

20592-501: Was present in most early societies and is attested to in the records of the earliest historical societies , including those of the Middle East , India , and China . By the Hellenic period of ancient Greece , a concerted causal study of disease was underway (see Medicine in ancient Greece ), with many notable early physicians (such as Hippocrates , for whom the modern Hippocratic Oath

20736-452: Was the first hominin species to leave Africa and disperse across Eurasia. Perhaps as early as 1.5 million years ago, but certainly by 250,000 years ago, hominins began to use fire for heat and cooking. Beginning about 500,000 years ago, Homo diversified into many new species of archaic humans such as the Neanderthals in Europe, the Denisovans in Siberia , and the diminutive H. floresiensis in Indonesia . Human evolution

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