Finches' Beaks

New York State's Regents Exam for Living Environment includes questions that are based on 4 required lab activities. One of those labs is called The Beaks of Finches and is supposed to be a simulation of Natural Selection.

I wasn't impressed with the lab.

Let me first describe the idea. I would post the actual lab activity, but it is copyrighted by NY State and we are explicitly forbidden to distribute it except to NY State personnel involved in teaching it. In fact, the state does not make it available to us electronically, instead we must request hard copies directly from State Ed., so I wouldn't be able to post it anyway unless I scanned it myself.

There are other similar versions of the activity around: This one at Access Excellence is almost identical to the New York State version minus the student worksheets (It's the format and exact nature of the questions on the lab worksheets that are unique to NY State).

Basically, you need about 12 - 16 different grasping devices - tongs, tweezers, pliers, etc. - and 2 different kinds of seeds. I used extremely small lentils and fava beans. Students work in pairs, and try in 30 seconds to gather enough seeds to survive from a plate of seeds at each table. Average 13 seeds per round and you survive. Those who do not survive the first round (small seeds only) "migrate" to another island and try their beaks at larger seeds. In the second round, competition with another group is added to the activity. Anyone who doesn't survive the second round is "extinct."

The problem I had with both of my classes was that clearly technique was the deciding factor in surviving rather than the type of beak. I had small tweezers that come to a sharp point and large scissor-style tongs with wide flat tips (beaker tongs) and short heavy stubby pliers and variations on all those basic types. Absolutely no trend emerged that would allow students to see a connection between the type of beak and success in the struggle to survive. Granted, it is important for students to know that behavior (technique) can also be subject to natural selection, but that seems to me to be a finer point to stress AFTER students understand the basic concept as it relates to physical characteristics. Anyway, the activity is called Beaks of Finches, not Techniques of Finches. On that score, the activity fails miserably. Although there may be some interesting higher level discussions that could come out of this activity, for a demonstration of the basic principles of natural selection I would look for other simulations. It is probably not a coincidence that the June 2004 and the August 2004 Regents exams have not a single question about this lab (the other 3 required labs are represented in the questions). Sadly, I can think of some ways that it might have worked better, but teachers are warned to do the labs exactly as they are written or else the students may be disadvantaged by the way the questions on the exams might be worded.