page_title: Helia Bravo Hollis
section_title: Contributions to biology
hierarchical_section_title: Helia Bravo Hollis / Contributions to biology
caption_attribution_description: English: Cactus type of succulent plant
context_page_description: Helia Bravo Hollis was a Mexican botanist who did research in the Faculty of Science at UNAM.
context_section_description: Bravo worked in the field of zoology in the area of parasitic and free-living protozoa, publishing nine studies between 1921 and 1927 while still a student alongside Professor Isaac Ochoterena. She joined the teaching faculty at the National Preparatory School as a teaching assistant, and later as a professor.
  She was later invited to head the biology department at UNAM, which changed its name to Biology Institute of UNAM after the University became autonomous in 1929.
  In the 1950s, she returned to academic life and was a professor of botany at the National School of Biological Sciences of the Instituto Politécnico Nacional. Two years later she returned to the Institute of Biology at UNAM. It is during this period that she shared the leadership of the National Herbarium withDébora Ramírez Cantú.
  She made contributions to the area of floriculture, although in the arid regions of eastern Mexico, she focused on the taxonomy of cactaceae.  She organized a collection of live cactaceae and other succulent plants in order to observe their development and evaluate morphological characteristics.
  She co-founded the Mexican Cactus Society (Sociedad Mexicana de Cactología) in 1951 with Carlos Chávez, Dudley Blackburn Gold, Jorge Meyrán, Eizi Matuda, and Hernando Sanchez-Mejorada, and later helped to found the Botanical Gardens at UNAM in 1959, serving as its director in the 1960s. The Society published the magazine Cactáceas y suculentas mexicanas under the leadership of Jorge Meyrán. She specialized in the taxonomy of cactacea in Mexico, authoring an entire monograph on the Mesoamerican region.  She conducted fieldwork and worked in herbariums, disseminating her findings in publications, conferences, and in the classroom.
  Her scientific writings span over 160 publications, 60 taxonomy descriptions, and 59 reclassifications. She published her first work in Revista Mexicana de Biologia in 1921. Bravo published her first book in 1937. Her best-recognized work, Las Cactaceas de Mexico, was published in 1937. The work was written in Spanish and was over 700 pages in length. Bravo collaborated with Hernando Sanchez-Mejorada to update the book from 1978 to 1991. The work was then 3 volumes and had over 1,800 pages. Many of Bravo's articles were published in Cactaceasy Suculentas Mexicanas, the journal of the Mexican Cactus Society.
caption: Example of a succulent plant, the type of plants that Bravo studied
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