Randlane was born in Tallinn and completed her undergraduate studies at Tartu State University, graduating cum laude in 1977. She pursued further education at the same institution, obtaining her candidate's degree in 1986. Her thesis explored the lichen flora of Estonia's western islands. Randlane's professional journey at the University of Tartu began in 1975 when she started as a technician. She has maintained her affiliation with the university throughout her career, progressing to her current position as an associate professor.[2]
Randlane's research primarily concentrates on lichentaxonomy and ecology. Her publication record includes close to a hundred scientific papers and book chapters. One of her notable contributions is spearheading the development of a comprehensive global taxonomic database for cetrarioid lichens. A significant portion of her work has been dedicated to studying the lichen biodiversity of Estonia and the broader Baltic region.[2]
Beyond her research endeavors, Randlane has played a pivotal role in shaping Estonian lichenology. Her engaging lectures and field courses have inspired numerous students, fostering a new generation of lichen enthusiasts. She has also been committed to making lichen knowledge accessible to the public, co-authoring a multilingual series on Estonian macrolichens for a general audience. Randlane has contributed significantly to the development of online educational resources covering Estonian lichens, mosses, and vascular plants. Additionally, she has been actively involved in expanding the lichen herbarium at the University of Tartu, adding nearly 7,000 specimens that she collected and identified.[2]
Randlane's contributions have been recognised with several accolades from the University of Tartu. She received the university medal in 2003, followed by the medal of honour a decade later in 2013. In 2021, she was awarded a special medal commemorating "100 semesters at the University of Tartu". Her efforts in science communication were acknowledged in 2010 when interactive online identification guides she helped develop won the top prize for innovative science popularisation in Estonia. In recognition of her significant contributions to the field, the 60th issue of Folia Cryptogamica Estonica was dedicated to Randlane on the occasion of her 70th birthday.[2] The lichen species Pyxine tiinae,[3]Leptogium tiinae,[4] and Lepraria tiinae were named in her honour in this issue.[5]
