Question: What kind of early 20th century music were Collins and Harlan known for?

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Florrie Forde: Florrie Forde (16 August 187518 April 1940), born Flora May Augusta Flannagan, was an Australian popular singer and vaudevillian entertainer.  From 1897 she lived and worked in the United Kingdom.  She was one of the most popular stars of the early 20th century music hall.

R. Crumb and his Cheap Suit Serenaders No. 2: R. Crumb and his Cheap Suit Serenaders Number 2 is the second 33⅓ rpm album by the retro string band R. Crumb & His Cheap Suit Serenaders and its subtitle was "Persian Rug, Crying My Blues Away, Moana March and Other Favorites".  The album was later retitled Chasin' Rainbows in re-release on CD (Shanachie 6002, 1993 - ASIN: B000000DSO) from Shanachie Records.  The band's personnel includes Robert Crumb on lead vocal and banjo, Allan Dodge on mandolin, violin, ukulele and vocals, Robert Armstrong on guitars, accordion, banjo, musical saw and vocals, Terry Zwigoff, who later produced the documentary "Crumb", on cello.  Originally released on Blue Goose Records in 1976, this record became a collectible not only for the whimsical string band renditions of and reminiscent of the early 20th century music, but for the cover art drawn by the band's frontman and well-known comics artist Robert Crumb.

History of ecology: Ecology is a new science and considered as an important branch of biological science, having only become prominent during the second half of the 20th century.  Ecological thought is derivative of established currents in philosophy, particularly from ethics and politics.  Its history stems all the way back to the 4th century.  One of the first ecologists whose writings survive may have been Aristotle or perhaps his student, Theophrastus, both of whom had interest in many species of animals and plants.  Theophrastus described interrelationships between animals and their environment as early as the 4th century BC.  Ecology developed substantially in the 18th and 19th century.  It began with Carl Linnaeus and his work with the economy of nature.  Soon after came Alexander von Humboldt and his work with botanical geography.  Alfred Russel Wallace and Karl Möbius then contributed with the notion of biocoenosis.  Eugenius Warming’s work with ecological plant geography led to the founding of ecology as a discipline.  Charles Darwin’s work also contributed to the science of ecology, and Darwin is often attributed with progressing the discipline more than anyone else in its young history.  Ecological thought expanded even more in the early 20th century.  Major contributions included: Eduard Suess’ and Vladimir Vernadsky’s work with the biosphere, Arthur Tansley’s ecosystem, Charles Elton's "Animal Ecology", and Henry Cowles ecological succession.  Ecology influenced the social sciences and humanities.  Human ecology began in the early 20th century and it recognized humans as an ecological factor.  Later James Lovelock advanced views on earth as a macro-organism with the Gaia hypothesis.  Conservation stemmed from the science of ecology.  Important figures and movements include Shelford and the ESA, National Environmental Policy act, George Perkins Marsh, Theodore Roosevelt, Stephen A. Forbes, and post-Dust Bowl conservation.  Later in the 20th century world governments collaborated on man’s effects on the biosphere and Earth’s environment.

Encarnación de Díaz: Encarnación de Díaz is a town and municipality located in the far northeast of the state of Jalisco in north central Mexico.  It is located in a natural pass that connects the Los Altos region of Jalisco to points north, and from pre Hispanic times until the 20th century, it was a major thoroughfare for north-south travel.  The town began as a way station along a road built through this pass in the 17th century, formally becoming a town in 1760.  It began to function as a municipality in the latter 19th century, but this status was not confirmed until the early 20th.  Transport, along with numerous prosperous haciendas supported the economy of the area until the early 20th century, when travel patterns and the Mexican Revolution spurred its decline.  In the 1920s, it was a center of rebellion during the Cristero War, and the town contains Mexico’s only museum exclusively dedicated to this episode in history.  It also contains a museum dedicated to various naturally occurring mummies which have been found in the municipal cemetery.

Harlan House Hotel: The Harlan House Hotel is a historic building located in Mount Pleasant, Iowa, United States.  It is associated with James Harlan, the first Republican to represent Iowa in the United States Senate (1855-1865, 1867-1872).  He was also Secretary of the Interior (1865-1867).  His daughter Mary was the wife of Robert Todd Lincoln, President Abraham Lincoln's only surviving son.  Harlan built the oldest part of this building as his house in 1857.  After his career as a Senator, he could no longer afford the house and bought another house in Mount Pleasant.  Harlan built the first addition onto his old house and converted it into a hotel so he could support himself.  He added onto the hotel two more time, c. 1880 and 1892.  The first two additions are on the alley side of the building, and the third addition faces Jefferson Street.  The middle section of the building with the bracketed cornice and mansard roof is the original house.  Harlan moved into the hotel in the early 1890s and died here in 1899.  A few minor alterations were made to the building in the 20th century.  It was listed on the National Register of Historic Places in 1987.

Rockdale (Fallston, Maryland): Rockdale, also known as The Robinson/Stirling Place, is a historic home and farm complex located at Fallston, Harford County, Maryland, United States.  It is a farm developed from the late 18th century through the early 20th century.  The dwelling is in three parts.  The east room of the east wing is the earliest section dating from the 18th century.  The largest or main portion of the dwelling dates from between 1815 and 1830.  The north wing, a bay centered in the south façade of the second story, and a small conservatory, date from the very early 20th century.  The main house is five bays in length, two and a half stories, of stone construction, stuccoed and scored.  The home is surrounded by several outbuildings, trees, and other plantings, and the remains of formal gardens and garden structures developed in the early 20th century.  It was the residence of William E. Robinson (1860-1935), an entrepreneur in the local canning industry.

Collins &amp; Harlan: Collins & Harlan, the team of Arthur Collins and Byron G. Harlan formed a popular comic duet between 1903 and 1926.  They sang ragtime standards as well as what were known as "Coon songs" – music sung by white performers in a black dialect.  Their material also employed many other stereotypes of the time including Irishmen and farmers.  Fellow recording artist Billy Murray nicknamed them "The Half-Ton Duo" as both men were rather overweight.  Collins and Harlan produced many number one hits with recordings of minstrel songs such as "My Gal Irene", "I Know Dat I'll be Happy Til I Die", "Who Do You Love?"  and "Down Among the Sugarcane".  Their song "That Funny Jas Band from Dixieland", recorded November 8, 1916, is among the first recorded uses of the word "jas" which eventually evolved to "jass", and to the current spelling "jazz".

Erwin Mill: Erwin Mill was a textile mill in Durham, North Carolina that operated between the years of 1893 and 1986.  After seeing the success of other cotton mills in the Northeast and locally in Durham, entrepreneur Benjamin N. Duke incorporated the mill in 1892 and recruited William H. Erwin to manage the enterprise.  The mill’s success in the late 19th and early 20th centuries was the result of Erwin’s and his successors’ exceptional management tactics, even when the factory hit obstacles such as the Great Depression and the unionization of its workers.  The mill grew quickly in the late 19th century and early 20th century, became one of North Carolina’s largest cotton mills.  It originally produced muslin pouches for tobacco, but the mill would later expand its production to other fabrics, becoming one of the largest producers of denim in the world during the early 1900s.  Workers at the mill enjoyed some of the best working conditions and highest wages in textile factories throughout the southern United States.  Mill employees would later sign union-friendly labor agreements that were radical to the southern textile industry in the early to mid 20th century.  The establishment of homes, businesses and recreation areas in the mill village was a significant factor in the development of the West Durham, especially the Ninth Street business district and the Old West Durham Neighborhood.  Erwin Mill No. 1 is on the National Register of Historic Places and the mill village of West Durham is a National Historic District.  An apartment complex, office building and shopping center of the same name that are built on the original site also commemorate the factory.

Coon song: Coon songs were a genre of music that presented a stereotyped image of Blacks.  They were popular in the United States and the United Kingdom from around 1880 to 1920, though the earliest such songs date from minstrel shows as far back as 1848.

Baritenor: Baritenor (also rendered in English language sources as bari-tenor or baritenore) is a portmanteau (blend) of the words "baritone" and "tenor".  It is used to describe both baritone and tenor voices.  In "Webster's Third New International Dictionary" it is defined as "a baritone singing voice with virtually a tenor range".  However, the term was defined in several late 19th century and early 20th century music dictionaries, such as "The American History and Encyclopedia of Music", as "a low tenor voice, almost barytone" ["sic"].

Supporting paragraphs: Collins &amp; Harlan Coon song
Answer: Coon songs