Advanced Mobile Phone System
Advanced Mobile Phone System was an analog mobile phone system standard developed by Bell Labs, introduced in the Americas on October 13, 1983, Israel in 1986, Australia in 1987, Singapore in 1988, Pakistan in 1990. It was the primary analog mobile phone system in North America into the 2000s; as of February 18, 2008, carriers in the United States were no longer required to support AMPS and companies such as AT&T and Verizon Communications have discontinued this service permanently. AMPS was discontinued in Australia in September 2000, in Pakistan by October 2004, in Israel by January 2010, Brazil by 2010; the first cellular network efforts began with research conducted at Motorola. In 1960, John F. Mitchell, an electrical engineer who had graduated from the Illinois Institute of Technology, became Motorola's chief engineer for its mobile-communication products. Mitchell oversaw the marketing of the first pager to use transistors. Motorola had long produced mobile telephones for automobiles, but these large and heavy models consumed too much power to allow their use without the automobile's engine running.
Mitchell's team, which included the gifted Dr. Martin Cooper, developed portable cellular telephony, Mitchell was among the Motorola employees granted a patent for this work in 1973; the first call on the prototype connected to a wrong number. While Motorola was developing a cellular phone, from 1968-1983 Bell Labs worked out a system called Advanced Mobile Phone System, which became the first cellular network standard in the United States; the first system was deployed in Chicago, Illinois, in 1979. Motorola and others built the cellular phones for this and other cellular systems. Martin Cooper, a former general manager for the systems division at Motorola, led a team that produced the DynaTAC8000x, the first commercially available cellular phone small enough to be carried, made the first phone call from it, he introduced the so-called Bag Phone. In 1992 the first smartphone, called IBM Simon, used AMPS. Frank Canova led its design at IBM and it was demonstrated that year at the COMDEX computer-industry trade-show.
A refined version of the product was marketed to consumers in 1994 by BellSouth under the name Simon Personal Communicator. The Simon was the first device that can be properly referred to as a "smartphone" though that term was not yet coined. AMPS is a first-generation cellular technology that uses separate frequencies, or "channels", for each conversation, it therefore required considerable bandwidth for a large number of users. In general terms, AMPS was similar to the older "0G" Improved Mobile Telephone Service, but used more computing power in order to select frequencies, hand off conversations to PSTN lines, handle billing and call setup. What separated AMPS from older systems is the "back end" call setup functionality. In AMPS, the cell centers could flexibly assign channels to handsets based on signal strength, allowing the same frequency to be re-used in various locations without interference; this allowed a larger number of phones to be supported over a geographical area. AMPS pioneers coined the term "cellular" because of its use of small hexagonal "cells" within a system.
AMPS suffered from many weaknesses compared to today's digital technologies. As an analog standard, it was susceptible to static and noise, there was no protection from'eavesdropping' using a scanner. In the 1990s an epidemic of "cloning" cost the cellular carriers millions of dollars. An eavesdropper with specialized equipment could intercept a handset's ESN and MDN or CTN; the Electronic Serial Number, a 12-digit number sent by the handset to the cellular system for billing purposes, uniquely identified that phone on the network. The system allowed or disallowed calls and/or features based on its customer file. A person intercepting an ESN/MDN pair could clone the combination onto a different phone and use it in other areas for making calls without paying. Cellular phone cloning became possible with off-the-shelf technology in the 1990s. Would-be cloners required three key items: A radio receiver, such as the Icom PCR-1000, that could tune into the Reverse Channel A PC with a sound card and a software program called Banpaia A phone that could be used for cloning, such as the Oki 900The radio, when tuned to the proper frequency, would receive the signal transmitted by the cell phone to be cloned, containing the phone's ESN/MDN pair.
This signal would feed into the sound-card audio-input of the PC, Banpaia would decode the ESN/MDN pair from this signal and display it on the screen. The hacker could copy that data into the Oki 900 phone and reboot it, after which the phone network could not distinguish the Oki from the original phone whose signal had been received; this gave the cloner, through the Oki phone, the ability to use the mobile-phone service of the legitimate subscriber whose phone was cloned - just as if that phone had been physically stolen, except that the subscriber retained his or her phone, unaware that the phone had been cloned—at least until that subscriber received his or her next bill. The problem became so large; the cellular companies initiated a system called RF Fingerprinting, whereby it could determine subtle differences in the signal of one phone from another and shut down some cloned phones. Some legitimate customers had problems with this though if they made certai
The Universal Mobile Telecommunications System is a third generation mobile cellular system for networks based on the GSM standard. Developed and maintained by the 3GPP, UMTS is a component of the International Telecommunications Union IMT-2000 standard set and compares with the CDMA2000 standard set for networks based on the competing cdmaOne technology. UMTS uses wideband code division multiple access radio access technology to offer greater spectral efficiency and bandwidth to mobile network operators. UMTS specifies a complete network system, which includes the radio access network, the core network and the authentication of users via SIM cards; the technology described in UMTS is sometimes referred to as Freedom of Mobile Multimedia Access or 3GSM. Unlike EDGE and CDMA2000, UMTS requires new base stations and new frequency allocations. UMTS supports maximum theoretical data transfer rates of 42 Mbit/s when Evolved HSPA is implemented in the network. Users in deployed networks can expect a transfer rate of up to 384 kbit/s for Release'99 handsets, 7.2 Mbit/s for High-Speed Downlink Packet Access handsets in the downlink connection.
These speeds are faster than the 9.6 kbit/s of a single GSM error-corrected circuit switched data channel, multiple 9.6 kbit/s channels in High-Speed Circuit-Switched Data and 14.4 kbit/s for CDMAOne channels. Since 2006, UMTS networks in many countries have been or are in the process of being upgraded with High-Speed Downlink Packet Access, sometimes known as 3.5G. HSDPA enables downlink transfer speeds of up to 21 Mbit/s. Work is progressing on improving the uplink transfer speed with the High-Speed Uplink Packet Access. Longer term, the 3GPP Long Term Evolution project plans to move UMTS to 4G speeds of 100 Mbit/s down and 50 Mbit/s up, using a next generation air interface technology based upon orthogonal frequency-division multiplexing; the first national consumer UMTS networks launched in 2002 with a heavy emphasis on telco-provided mobile applications such as mobile TV and video calling. The high data speeds of UMTS are now most utilised for Internet access: experience in Japan and elsewhere has shown that user demand for video calls is not high, telco-provided audio/video content has declined in popularity in favour of high-speed access to the World Wide Web—either directly on a handset or connected to a computer via Wi-Fi, Bluetooth or USB.
UMTS combines three different terrestrial air interfaces, GSM's Mobile Application Part core, the GSM family of speech codecs. The air interfaces are called UMTS Terrestrial Radio Access. All air interface options are part of ITU's IMT-2000. In the most popular variant for cellular mobile telephones, W-CDMA is used, it is called "Uu interface", as it links User Equipment to the UMTS Terrestrial Radio Access Network Please note that the terms W-CDMA, TD-CDMA and TD-SCDMA are misleading. While they suggest covering just a channel access method, they are the common names for the whole air interface standards. W-CDMA or WCDMA, along with UMTS-FDD, UTRA-FDD, or IMT-2000 CDMA Direct Spread is an air interface standard found in 3G mobile telecommunications networks, it supports conventional cellular voice, text and MMS services, but can carry data at high speeds, allowing mobile operators to deliver higher bandwidth applications including streaming and broadband Internet access. W-CDMA uses the DS-CDMA channel access method with a pair of 5 MHz wide channels.
In contrast, the competing CDMA2000 system uses one or more available 1.25 MHz channels for each direction of communication. W-CDMA systems are criticized for their large spectrum usage, which delayed deployment in countries that acted slowly in allocating new frequencies for 3G services; the specific frequency bands defined by the UMTS standard are 1885–2025 MHz for the mobile-to-base and 2110–2200 MHz for the base-to-mobile. In the US, 1710–1755 MHz and 2110–2155 MHz are used instead, as the 1900 MHz band was used. While UMTS2100 is the most deployed UMTS band, some countries' UMTS operators use the 850 MHz and/or 1900 MHz bands, notably in the US by AT&T Mobility, New Zealand by Telecom New Zealand on the XT Mobile Network and in Australia by Telstra on the Next G network; some carriers such as T-Mobile use band numbers to identify the UMTS frequencies. For example, Band I, Band IV, Band V. UMTS-FDD is an acronym for Universal Mobile Telecommunications System - frequency-division duplexing and a 3GPP standardized version of UMTS networks that makes use of frequency-division duplexing for duplexing over an UMTS Terrestrial Radio Access air interface.
W-CDMA is the basis of Japan's NTT DoCoMo's FOMA service and the most-commonly used member of the Universal Mobile Telecommunications System family and sometimes used as a synonym for UMTS. It uses the DS-CDMA channel access method and the FDD duplexing method to achieve higher speeds and support more users compared to most used time division multiple access and time division duplex schemes. While not an evolutionary upgrade on the airside, it uses the same core network as the 2G GSM networks deployed worldwide, allowing dual mode mobile operation al
Paraguay the Republic of Paraguay, is a country of South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, Bolivia to the northwest. Although it is one of the only two landlocked countries in South America, the country has coasts and ports on the Paraguay and Paraná rivers that give exit to the Atlantic Ocean through the Paraná-Paraguay Waterway. Due to its central location in South America, it is sometimes referred to as Corazón de Sudamérica. Spanish conquistadores arrived in 1524 after navigating northwards from the Río de la Plata to the Paraná River, up the Paraguay River. In 1537, they established the city of Asunción, the first capital of the Governorate of Paraguay and Río de la Plata. Paraguay was the epicenter of the Jesuit Missions, where the Guaraní people were educated and introduced to Christianity and European culture under the direction of the Society of Jesus in Jesuit reductions during the 17th century. However, after the expulsion of the Jesuits from Spanish territories in 1767, Paraguay became a peripheral colony, with few urban centers and settlers.
Following independence from Spain at the beginning of the 19th century, Paraguay was ruled by a series of authoritarian governments who implemented nationalist and protectionist policies. This period ended with the disastrous Paraguayan War, during which Paraguay lost at least 50% of its prewar population and around 25–33% of its territory to the Triple Alliance of Argentina and Uruguay. In the 20th century, Paraguay faced another major international conflict – the Chaco War – against Bolivia, from which the Paraguayans emerged victorious. Afterwards, the country entered a period of military dictatorships, ending with the 35 year regime of Alfredo Stroessner that lasted until he was toppled in 1989 by an internal military coup; this marked the beginning of the "democratic era" of Paraguay. With around 7 million inhabitants, Paraguay is a founding member of Mercosur, an original member of the United Nations, the Organization of American States, the Non-Aligned Movement and the Lima Group; the city of Luque, in Asuncion's Metropolitan Area, is the seat of the CONMEBOL.
The Guarani culture is influential and more than 90% of the people speak different forms of the Guarani language on top of Spanish. Paraguayans are known for being a happy and easy-living people and many times the country topped the "world's happiest place" charts because of the "positive experiences" lived and expressed by the population; the indigenous Guaraní had been living in eastern Paraguay for at least a millennium before the arrival of the Spanish. Western Paraguay, the Gran Chaco, was inhabited by nomads of whom the Guaycuru peoples were the most prominent; the Paraguay River was the dividing line between the agricultural Guarani people to the east and the nomadic and semi-nomadic people to the west in the Gran Chaco. The Guarcuru nomads were known for their warrior traditions and were not pacified until the late 19th century; these indigenous tribes belonged to five distinct language families, which were the bases of their major divisions. Differing language speaking groups were competitive over resources and territories.
They were further divided into tribes by speaking languages in branches of these families. Today 17 separate ethnolinguistic groups remain; the first Europeans in the area were Spanish explorers in 1516. The Spanish explorer Juan de Salazar de Espinosa founded the settlement of Asunción on 15 August 1537; the city became the center of a Spanish colonial province of Paraguay. An attempt to create an autonomous Christian Indian nation was undertaken by Jesuit missions and settlements in this part of South America in the eighteenth century, which included portions of Uruguay and Brazil, they developed Jesuit reductions to bring Guarani populations together at Spanish missions and protect them from virtual slavery by Spanish settlers and Portuguese slave raiders, the Bandeirantes. In addition to seeking their conversion to Christianity. Catholicism in Paraguay was influenced by the indigenous peoples; the reducciones flourished in eastern Paraguay for about 150 years, until the expulsion of the Jesuits by the Spanish Crown in 1767.
The ruins of two 18th-century Jesuit Missions of La Santísima Trinidad de Paraná and Jesús de Tavarangue have been designated as World Heritage Sites by UNESCO. In western Paraguay Spanish settlement and Christianity were resisted by the nomadic Guaycuru and other nomads from the 16th century onward. Most of these peoples were absorbed into the mestizo population in the 19th centuries. Paraguay overthrew the local Spanish administration on 14 May 1811. Paraguay's first dictator was José Gaspar Rodríguez de Francia who ruled Paraguay from 1814 until his death in 1840, with little outside contact or influence, he intended to create a utopian society based on the French theorist Jean-Jacques Rousseau's Social Contract. Rodríguez de Francia established new laws that reduced the powers of the Catholic church and the cabinet, forbade colonial citizens from marrying one another and allowed them to marry only blacks, mulattoes or natives, in order to break the power of colonial-era elites and to create a mixed-race or mestizo society.
He cut off the rest of South America. Because of Francia's restrictions of freedom, Fulgencio Yegros and several other Independence-era
Argentina the Argentine Republic, is a country located in the southern half of South America. Sharing the bulk of the Southern Cone with Chile to the west, the country is bordered by Bolivia and Paraguay to the north, Brazil to the northeast and the South Atlantic Ocean to the east, the Drake Passage to the south. With a mainland area of 2,780,400 km2, Argentina is the eighth-largest country in the world, the fourth largest in the Americas, the largest Spanish-speaking nation; the sovereign state is subdivided into twenty-three provinces and one autonomous city, Buenos Aires, the federal capital of the nation as decided by Congress. The provinces and the capital exist under a federal system. Argentina claims sovereignty over part of Antarctica, the Falkland Islands, South Georgia and the South Sandwich Islands; the earliest recorded human presence in modern-day Argentina dates back to the Paleolithic period. The Inca Empire expanded to the northwest of the country in Pre-Columbian times; the country has its roots in Spanish colonization of the region during the 16th century.
Argentina rose as the successor state of the Viceroyalty of the Río de la Plata, a Spanish overseas viceroyalty founded in 1776. The declaration and fight for independence was followed by an extended civil war that lasted until 1861, culminating in the country's reorganization as a federation of provinces with Buenos Aires as its capital city; the country thereafter enjoyed relative peace and stability, with several waves of European immigration radically reshaping its cultural and demographic outlook. The almost-unparalleled increase in prosperity led to Argentina becoming the seventh wealthiest nation in the world by the early 20th century. Following the Great Depression in the 1930s, Argentina descended into political instability and economic decline that pushed it back into underdevelopment, though it remained among the fifteen richest countries for several decades. Following the death of President Juan Perón in 1974, his widow, Isabel Martínez de Perón, ascended to the presidency, she was overthrown in 1976 by a U.
S.-backed coup which installed a right-wing military dictatorship. The military government persecuted and murdered numerous political critics and leftists in the Dirty War, a period of state terrorism that lasted until the election of Raúl Alfonsín as President in 1983. Several of the junta's leaders were convicted of their crimes and sentenced to imprisonment. Argentina is a prominent regional power in the Southern Cone and Latin America, retains its historic status as a middle power in international affairs. Argentina has the second largest economy in South America, the third-largest in Latin America, membership in the G-15 and G-20 major economies, it is a founding member of the United Nations, World Bank, World Trade Organization, Union of South American Nations, Community of Latin American and Caribbean States and the Organization of Ibero-American States. Despite its history of economic instability, it ranks second highest in the Human Development Index in Latin America; the description of the country by the word Argentina has been found on a Venetian map in 1536.
In English the name "Argentina" comes from the Spanish language, however the naming itself is not Spanish, but Italian. Argentina means in Italian " of silver, silver coloured" borrowed from the Old French adjective argentine " of silver" > "silver coloured" mentioned in the 12th century. The French word argentine is the feminine form of argentin and derives from argent "silver" with the suffix -in; the Italian naming "Argentina" for the country implies Terra Argentina "land of silver" or Costa Argentina "coast of silver". In Italian, the adjective or the proper noun is used in an autonomous way as a substantive and replaces it and it is said l'Argentina; the name Argentina was first given by the Venetian and Genoese navigators, such as Giovanni Caboto. In Spanish and Portuguese, the words for "silver" are plata and prata and " of silver" is said plateado and prateado. Argentina was first associated with the silver mountains legend, widespread among the first European explorers of the La Plata Basin.
The first written use of the name in Spanish can be traced to La Argentina, a 1602 poem by Martín del Barco Centenera describing the region. Although "Argentina" was in common usage by the 18th century, the country was formally named "Viceroyalty of the Río de la Plata" by the Spanish Empire, "United Provinces of the Río de la Plata" after independence; the 1826 constitution included the first use of the name "Argentine Republic" in legal documents. The name "Argentine Confederation" was commonly used and was formalized in the Argentine Constitution of 1853. In 1860 a presidential decree settled the country's name as "Argentine Republic", that year's constitutional amendment ruled all the names since 1810 as valid. In the English language the country was traditionally called "the Argentine", mimicking the typical Spanish usage la Argentina and resulting from a mistaken shortening of the fuller name'Argentine Republic'.'The Argentine' fell out of fashion during the mid-to-late 20th century, now the country is referred to as "Argentina".
In the Spanish language "Argentina" is feminine, taking the feminine article "La" as the i
Chief executive officer
The chief executive officer or just chief executive, is the most senior corporate, executive, or administrative officer in charge of managing an organization – an independent legal entity such as a company or nonprofit institution. CEOs lead a range of organizations, including public and private corporations, non-profit organizations and some government organizations; the CEO of a corporation or company reports to the board of directors and is charged with maximizing the value of the entity, which may include maximizing the share price, market share, revenues or another element. In the non-profit and government sector, CEOs aim at achieving outcomes related to the organization's mission, such as reducing poverty, increasing literacy, etc. In the early 21st century, top executives had technical degrees in science, engineering or law; the responsibility of an organization's CEO are set by the organization's board of directors or other authority, depending on the organization's legal structure.
They can be far-reaching or quite limited and are enshrined in a formal delegation of authority. Responsibilities include being a decision maker on strategy and other key policy issues, leader and executor; the communicator role can involve speaking to the press and the rest of the outside world, as well as to the organization's management and employees. As a leader of the company, the CEO or MD advises the board of directors, motivates employees, drives change within the organization; as a manager, the CEO/MD presides over the organization's day-to-day operations. The term refers to the person who makes all the key decisions regarding the company, which includes all sectors and fields of the business, including operations, business development, human resources, etc; the CEO of a company is not the owner of the company. In some countries, there is a dual board system with two separate boards, one executive board for the day-to-day business and one supervisory board for control purposes. In these countries, the CEO presides over the executive board and the chairman presides over the supervisory board, these two roles will always be held by different people.
This ensures a distinction between management by the executive board and governance by the supervisory board. This allows for clear lines of authority; the aim is to prevent a conflict of interest and too much power being concentrated in the hands of one person. In the United States, the board of directors is equivalent to the supervisory board, while the executive board may be known as the executive committee. In the United States, in business, the executive officers are the top officers of a corporation, the chief executive officer being the best-known type; the definition varies. In the case of a sole proprietorship, an executive officer is the sole proprietor. In the case of a partnership, an executive officer is a managing partner, senior partner, or administrative partner. In the case of a limited liability company, executive officer is any manager, or officer. A CEO has several subordinate executives, each of whom has specific functional responsibilities referred to as senior executives, executive officers or corporate officers.
Subordinate executives are given different titles in different organizations, but one common category of subordinate executive, if the CEO is the president, is the vice-president. An organization may have more than one vice-president, each tasked with a different area of responsibility; some organizations have subordinate executive officers who have the word chief in their job title, such as chief operating officer, chief financial officer and chief technology officer. The public relations-focused position of chief reputation officer is sometimes included as one such subordinate executive officer, but, as suggested by Anthony Johndrow, CEO of Reputation Economy Advisors, it can be seen as "simply another way to add emphasis to the role of a modern-day CEO – where they are both the external face of, the driving force behind, an organisation culture". In the US, the term chief executive officer is used in business, whereas the term executive director is used in the not-for-profit sector; these terms are mutually exclusive and refer to distinct legal duties and responsibilities.
Implicit in the use of these titles, is that the public not be misled and the general standard regarding their use be applied. In the UK, chief executive and chief executive officer are used in both business and the charitable sector; as of 2013, the use of the term director for senior charity staff is deprecated to avoid confusion with the legal duties and responsibilities associated with being a charity director or trustee, which are non-executive roles. In the United Kingdom, the term director is used instead of chief officer". Business publicists since the days of Edward Bernays and his client John D. Rockefeller and more the corporate publicists for Henry Ford, promoted the concept of the "celebrity CEO". Business journalists have adopted this approach, which assumes that the corporate achievements in the arena of manufacturing, wer
Panama the Republic of Panama, is a country in Central America, bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, the Pacific Ocean to the south. The capital and largest city is Panama City, whose metropolitan area is home to nearly half the country's 4 million people. Panama was inhabited by indigenous tribes before Spanish colonists arrived in the 16th century, it broke away from Spain in 1821 and joined the Republic of Gran Colombia, a union of Nueva Granada and Venezuela. After Gran Colombia dissolved in 1831, Panama and Nueva Granada became the Republic of Colombia. With the backing of the United States, Panama seceded from Colombia in 1903, allowing the construction of the Panama Canal to be completed by the US Army Corps of Engineers between 1904 and 1914; the 1977 Torrijos–Carter Treaties led to the transfer of the Canal from the United States to Panama on December 31, 1999. Revenue from canal tolls continues to represent a significant portion of Panama's GDP, although commerce and tourism are major and growing sectors.
It is regarded as a high-income country. In 2015 Panama ranked 60th in the world in terms of the Human Development Index. In 2018, Panama was ranked seventh-most competitive economy in Latin America, according to the World Economic Forum's Global Competitiveness Index. Covering around 40 percent of its land area, Panama's jungles are home to an abundance of tropical plants and animals – some of them found nowhere else on the planet. Panama is a founding member of the United Nations and other international organizations such as OAS, LAIA, G77, WHO and NAM; the definite origin of the name Panama is unknown. There are several theories. One postulates that the country was named after a found species of tree. Another that the first settlers arrived in Panama in August, when butterflies abound, that the name means "many butterflies" in one or several of indigenous Amerindian languages that were spoken in the territory prior to Spanish colonization. Most scientifically corroborated theory, that by Panamanian linguists, states that the word is a hispanicization of Kuna language word "bannaba" which means "distant" or "far away".
A relayed legend in Panama is that there was a fishing village that bore the name "Panamá", which purportedly meant "an abundance of fish", when the Spanish colonizers first landed in the area. The exact location of the village is unspecified; the legend is corroborated by Captain Antonio Tello de Guzmán's diary entries, who reports landing at an unnamed village while exploring the Pacific coast of Panama in 1515. In 1517, Don Gaspar de Espinosa, a Spanish lieutenant, decided to settle a post in the same location Guzmán described. In 1519, Pedrarias Dávila decided to establish the Spanish Empire's Pacific port at the site; the new settlement replaced Santa María La Antigua del Darién, which had lost its function within the Crown's global plan after the Spanish exploitation of the riches in the Pacific began. The official definition and origin of the name as promoted by Panama's Ministry of Education is the "abundance of fish and butterflies"; this is the usual description given in social studies textbooks.
At the time of the arrival of the Spanish in the 16th century, the known inhabitants of Panama included the Cuevas and the Coclé tribes. These people have nearly disappeared; the Isthmus of Panama was formed about three million years ago when the land bridge between North and South America became complete, plants and animals crossed it in both directions. The existence of the isthmus affected the dispersal of people and technology throughout the American continent from the appearance of the first hunters and collectors to the era of villages and cities; the earliest discovered artifacts of indigenous peoples in Panama include Paleo-Indian projectile points. Central Panama was home to some of the first pottery-making in the Americas, for example the cultures at Monagrillo, which date back to 2500–1700 BC; these evolved into significant populations best known through their spectacular burials at the Monagrillo archaeological site, their beautiful Gran Coclé style polychrome pottery. The monumental monolithic sculptures at the Barriles site are important traces of these ancient isthmian cultures.
Before Europeans arrived Panama was settled by Chibchan and Cueva peoples. The largest group were the Cueva; the size of the indigenous population of the isthmus at the time of European colonization is uncertain. Estimates range as high as two million people, but more recent studies place that number closer to 200,000. Archaeological finds and testimonials by early European explorers describe diverse native isthmian groups exhibiting cultural variety and suggesting people developed by regular regional routes of commerce; when Panama was colonized, the indigenous peoples fled into nearby islands. Scholars believe that infectious disease was the primary cause of the population decline of American natives; the indigenous peoples had no acquired immunity to diseases, chronic in Eurasian populations for centuries. Rodrigo de Bastidas sailed westward from Venezuela in 1501 in search of gold, became the first European to explore the isthmus of Panama. A year Christopher Columbus visited the isthmus, established a short-lived settlement in the Darien.
Vasco Núñez de Balboa's tortuous