The crustose coralline algae are a group of calcifying red algae that deposit calcium carbonate in the form of high-magnesium calcite, and thanks to the formation of calcifying skeletons, they play important roles in the framework construction and ecology of coral reefs. Coralline algae have a very long evolutionary history (>139 mya), but recent environmental anthropogenic stressors, such as ocean acidification threaten their persistence in tropical and temperate reefs. In this talk, I will discuss recent advances in the knowledge of the process of calcification (biomineralization) in tropical coralline algae, and the influence of the environment on the growth and calcification rates and mineralogical composition in these algae, particularly in the Great Barrier Reef (GBR). I will also give an overview of recent projects currently underway in the GBR and the Caribbean in collaboration with researchers from the Research School of Earth Sciences (ANU, Ulrike Troitzsch). This research is critical for advancing our understanding of the influence of human activities on the ecology and functional roles of coralline algae in benthic marine ecosystems.