These two activities support the Click & Learn Sorting Seashells, in which students consider the morphological characteristics of seashells to construct an evolutionary tree. Students use seashell cards as a pre-activity to explore grouping organisms by shared characteristics. As a post-activity, they construct an evolutionary tree using DNA sequences.

Using these cards, students make observations and sort the shells into groups in any way that makes sense to them — according to color, size, shape, or other characteristics. They then proceed through the online interactive to construct an evolutionary tree of the seashell species. They then compare their card groupings to the evolutionary relationships. After constructing a phylogenetic tree using the interactive, they revisit that classification using ClustalX, software that aligns and compares DNA sequences. They will then use a simple viewer program called NJplot to view the tree.