Life in the Fast Lane: From Hunted to Hunter

Lab Activity - Dissection of a Squid

Lab dissection of a squid, a member of Class Cephalopoda (along with the octopus and nautilus).  Supported by several Shape of Life segments, students interpret squid adaptations as a radical case of divergent evolution: A line of ancestral snails abandoned the life of sluggish grazing and foraging in favor of a new niche as speedy open water predators.  Students will understand that the shelled, but squid-like nautilus, is a “transitional form” en route to the swimming, shell-less cephalopods.  Finally, they use the squid to explore another macroevolutionary pattern: convergent evolution.  Students learn about the remarkable convergence of cephalopod and vertebrate “camera eyes,” and are then asked to brainstorm convergences among non-molluscs with the squid’s sharp beak, venomous saliva, streamlined shape, supportive inner shell, and grasping tentacles.

We provide both high school and middle school versions of this lesson. The instructor's guide applies to both versions.

This lesson was created by Kevin Goff, Virginia Institute of Marine Science educator.