Mexican biologist, Helia Bravo Hollis (or "Maestra Bravo" as she was known by her students) is well known for her huge contribution to the study of cacti in Mexico and the administration of the Botanic Gardens in Mexico City. However, she also published important works early on in her career on the protozoa of Mexico, which along with her botanical achievements culminated in 60 years devoted to the study of biology.

Growing up in the Federal District she undertook her early studies in various schools in Mexico City. Unfortunately the revolutions and armed conflict in the area in 1914 had a devastating affect on her family and her father was killed. She decided to enter the National Preparatory School in 1919, where she completed her bachillerato and took up courses in biology at the School of Higher Studies. Here she met Isaac Ochonterena and began to work with him, studying protozoa. Between 1921 and 1929 she published eight works on Phytomastigophora, Ciliophora and flagilates in the intestines of reptiles and amphibians, becoming a pioneer in the field of Mexican protozoa with her ex-professor.

In 1930 Bravo Hollis published her first botanic work in the first volume of Anales del Instituto Biología four months after the creation of this Institution within the National Autonomous University of Mexico (UNAM). Her thesis was a contribution to the Flora Mexicana with a monograph on the family Lemnaceae, the first floristic study of this group. At this time she began to work at the Institute of Biology and soon she graduated with a Masters in Natural Sciences, her thesis entitled Contribution to the Understanding of the Cacti of Tehuacan. From this point onwards she had a prolific career researching plant systematics, with a particular focus on Mexican cacti. In 1937 her book Las Cactaceas de México was published, bringing her to the forefront of the field.

During the 1940s she moved away from the university and her studies, but returned later, first as a botany lecturer at the Institute of Biological Sciences at the National Polytechnic Institute and later to UNAM as well. In 1951 Bravo Hollis co-founded the Mexican Cactology Society of which she was director and later honorary director. At this time she also began research at the National Herbarium (MEXU) where she remained until 1964. In the late 1950s she worked to promote the creation of a botanical garden at UNAM, passionately persuading important figures and authorities of its importance. In 1959 it was founded and Bravo Hollis was made its first director. Throughout the 1960s she ran the gardens passionately and was well respected, in one instance she was said to have paid workers from her own pocket when a strike had left them with no salary.

Having collected throughout Mexico and many parts of Mesoamerica, collecting a large number of live cacti and studying their morphology and taxonomy over many decades, Bravo Hollis amassed a great deal of knowledge. In total she published nearly 170 articles, two books, described 60 taxa and made 59 taxonomic revisions. She has received many awards and acknowledgements, including the 'Cactus d'Or' from the International Succulents Organisation, a doctorate Honoris causa and being made a Researcher Emeritus at UNAM, to name a few. Her works received worldwide acclaim from colleagues in the field and the genera Heliabravoa and Bravothrips are named in honour of her, as are six species and a subspecies. Today the desert garden at the Botanic Gardens of UNAM bears her name, as does a botanic garden and cactus collection at Zapotitlán de las Salinas, Puebla State. In 2000 a Biosphere reserve was created in Metztitlán, largely due to her floristic work in the area.

Sources:
Butanda, A. and Delgado Salinas, A., 1991, "Contribución a la Biología Mexicana por Helia Bravo Hollis: Una Guía Bibliográfica", Cuadernos del Instituto de Biología. 13

Helia Bravo-Hollis. Wikipedia:
http://es.wikipedia.org/wiki/Helia_Bravo_Hollis.