How do scientist estimate the number species?

Scientists estimate the number of species on Earth using various methods, including species inventorying, ecological surveys, and genetic analysis. They often extrapolate from known species in well-studied areas to predict the number of undiscovered species in less explored regions. Additionally, statistical models and biodiversity databases help researchers infer species richness based on environmental factors and historical data. Overall, estimates suggest that millions of species remain unidentified, particularly among microorganisms and invertebrates.