Question: Who was a founding father of the folk-song revival in England in the early 20th century and had a portait painted of them by Esther Blaikie MacKinnon?

<P0-S0> Cecil James Sharp (22 November 1859 – 23 June 1924) was the founding father of the folk-song revival in England in the early 20th century. <SEP> <P1-S0> Lucy Etheldred Broadwood (9 August 1858 – 22 August 1929) was an English folksong collector and researcher during the late 19th and early 20th centuries. <P1-S1>  As one of the founder members of the Folk-Song Society and Editor of the Folk Song Journal, she was one of the main influences of the English folk revival of that period. <P1-S2>  She was an accomplished singer, composer, piano accompanist, and amateur poet. <P1-S3>  She was much sought after as a song and choral singing adjudicator at music festivals throughout England, and was also one of the founders of the Leith Hill Music Festival in Surrey. <SEP> <P2-S0> Esther Blaikie MacKinnon (1885–1934) was a Scottish artist, who was known for her paintings and engravings. <P2-S1>  During her career, MacKinnon worked with a variety of media including paint, dry point, etchings, and black and white drawings. <P2-S2>  Notable were her portraits of Cecil and Evelyn Sharp, which currently are part of The National Portrait Gallery's primary collection. <P2-S3>  Her work was exhibited at the Royal Scottish Academy, the Royal Glasgow Institute, the Royal Academy, and the Society of Women Artists within her lifetime. <SEP> <P3-S0>  Ecology developed substantially in the 18th and 19th century. <P3-S1> 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. <P3-S2>  Its history stems all the way back to the 4th century. <P3-S3>  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. <P3-S4>  Ecology influenced the social sciences and humanities. <P3-S5>  Human ecology began in the early 20th century and it recognized humans as an ecological factor. <P3-S6>  Later James Lovelock advanced views on earth as a macro-organism with the Gaia hypothesis. <P3-S7>  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. <P3-S8>  Theophrastus described interrelationships between animals and their environment as early as the 4th century BC. <P3-S9>  Ecological thought is derivative of established currents in philosophy, particularly from ethics and politics. <P3-S10>  It began with Carl Linnaeus and his work with the economy of nature. <P3-S11>  Soon after came Alexander von Humboldt and his work with botanical geography. <P3-S12>  Conservation stemmed from the science of ecology. <P3-S13>  Eugenius Warming’s work with ecological plant geography led to the founding of ecology as a discipline. <P3-S14>  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.