In this lesson, students read and discuss selected and edited excerpts from the essays of Stephen Jay Gould on the subject of contrivances. Students learn that many features of modern organisms reflect the structure of their ancestors in ways that are not adaptive. They also learn that one of the best indicators of evolution is not the examples of perfect adaptations, but of the relatively imperfect ... Full description.

In this lesson, each student is given a block of wood and a screw (or nail), and is asked to put the screw into the block, without any tool (like a screwdriver or hammer). Their efforts, with varying success, lead to a discussion of contrivances, using various items and strategies as make-do (contrived) tools for which they were not intended, and an exploration of many examples of contrivances or ... Full description.

In this lesson, students are given a variety of materials and are asked to design a heat loss experiment that will result in a reasonable explanation of why whales do not have legs. Students will learn that natural selection favors a body design that is energy efficient. Full description.

A common criticism of natural selection is: How can it produce novel complex useful structures by pure random chance? Darwin argued that selection is not a random process, and furthermore, it is cumulative. This lesson provides a way for students to actually compare the cumulative non-random selection of Darwin with the non-cumulative version so often erroneously implied. Students attempt to produce ... Full description.

This introduction to the concept of biological complexity demystifies and debunks the argument of Paley that a complex watch is compelling evidence requiring a (complex) watchmaker (designer or creator). It employs a mathematical exercise to demonstrate this, involving a randomizing component (a die), and a simple mathematical rule (the non-random component), resulting in the repeated plotting of ... Full description.

This lesson teaches students that traits are usually favored by natural selection only when they result in more reproductively successful offspring. Students go out onto the school lawn and play the role of birds, picking up toothpick stick worms which have been previously scattered in equal numbers of green-stained and unstained. Birds are chased away before the worm population drops too low. Back ... Full description.

This lesson on natural selection shows students that population characteristics can change as a result of selective pressures operating over several generations. In the lesson, groups of students go hunting for beans in the lawn. Each group has a different tool (e.g. hand, spoon, fork, etc). There are three different colors of beans. The hunting goes for three rounds (generations), with extinctions ... Full description.

This lesson demonstrates how natural selection operates, using different colored paper chips to represent prey and a piece of fabric as a background (the environment). The predator (student) will hunt (select chips) to show that the best adapted, by color, are NOT chosen, and others which are poorly adapted (by standing out) ARE chosen (removed). Thus, the best adapted survive and reproduce to pass ... Full description.

This lesson is based on a video of recent field work on a twenty-two year study of finch beaks on a small island in the Galapagos, showing natural selection clearly operating in the wild. The video (which must be purchased) includes vignettes of the life of Darwin, and the Grant family working and living on the island. The lesson includes a video-notes worksheet, which helps to guide viewing for students, ... Full description.

This contrived natural selection simulation has students build and modify simple paper airplanes (Origami Birds). They demonstrate that: mutations occur randomly; selection is based on the immediate needs of the organism; inherited characteristics (whether mutated or not) are contingent; divergent evolution may occur when sub-populations face different environments; convergent evolution may result ... Full description.