INNOVATIONS Which Beak Fits the Bill? An Activity Examining Adaptation, Natural Selection and Evolution

Abstract: Evolution is a unifying concept within biology. In fact, Dobzhansky, a noted evolutionary biologist, argued, "Nothing in biology makes sense except in the light of evolution " (Dobzhansky, 1973). However, often students have misconceptions about evolution. There are a number of available activities where students use tools (representing bird beaks) to collect different food items. These activities enable students to see how various beaks are adapted to feeding on certain types of food. This article describes an inquiry-based activity that takes the process several steps further. In this inquiry-based activity, students not only examine adaptations that birds have for capturing prey, and changes in a bird population over time, but also hypothesize what would happen to the bird population if relative seed abundances change over time. Students then model an environmental change recorded by researchers when observing Darwin’s Finches. The Grant’s observed a severe drought in 1977 resulting in a drastic decline in seed production with small seeds being particularly affected (Grant, 1999; Boag & Grant 1981). Students then test their hypothesis and compare their findings to those observed by the Grants. This activity is well suited for students in general biology, ecology or evolution classes. Key words: Evolution, natural selection, adaptation, variation in population