Although Argentina harbours a notable increase in the academic community, achieving the highest number of researchers per capita in Latin America, the gender gap is still evident. The objective was to identify and evaluate the evolution of the main research themes in Argentinian ecology during the last 20 years to address whether social gender stereotypes were reproduced in research theme selection. We analysed four books of abstracts from the Argentinian Ecology conferences of the last 20 years and identified gender of the first author and co-authors. Natural Language Processing approach was used to analyse gender associations with the 16 319 words appearing in the 2208 titles of abstracts. The average number of female co-authors was always larger in female-led abstracts although the proportion of female co-authors/total authors increased the most in male-led abstracts. Research themes evolved from those considered cornerstones of ecology (e.g. population-oriented studies) to contemporary themes defined by Management and policy studies. Gender differences were present and changed with time. Currently, men work on research themes related to decision-making, while women focus on environmental processes therefore it is urgent to create more leadership spaces for women to reduce gender inequalities.