This example combines a pie chart and an area chart to visualize species distribution and temporal trends. The pie chart uses d3.pie and d3.arc to show the count of iris species from a CSV file loaded with d3.text, while the area chart uses d3.area with d3.scaleTime and d3.scaleLinear to display a simple time series. Both charts include legends and axes rendered via d3.axisBottom and d3.axisLeft.