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Life has recently been discovered on two planets, currently named Nearer and Farther. Survey expeditions are being undertaken to characterize life on each, with the objective of comparing the charcteristics of life on the two planets both with each other and with life on earth. The general effort is to better understand general properties of living systems.

Expeditionary groups have been formed to undertake an initial survey of "plant" life on Nearer and Farther. Plant life on earth is characterized by substantial diversity; there are a large number of different kinds of plants. The goal of the expeditionary groups is to try and determine whether diversity of plant life is an idiosyncracy of life on earth or a more general property of life wherever it is found.

You are a member of one such expeditionary group. Your group must return with a scheme for categorizing plant life on the planet assigned that is well motivated by your observations, clearly described, and yields a definite quantitative result for the numbers of kinds of plants on that planet. You will of course need to use understandings of the meaning of "plant" derived from experiences on earth, but you should not presume that categories of plant life on Nearer and Farther are necessarily similar to those on Earth. Your report should note presumptions about what plants are, be clear about what observations motivate your categorizing scheme, provide some indication of the level of confidence you have in your quantitative results, and discuss what further observations are motivated by your findings . A preliminary report of your studies will be presented at a conference on "Diversity in BioSystems: New Findings From Additional Cases", focused on the question of whether "diversity" is or is not a fundamental characteristic of living systems.

Your group should also publish a summary of its findings in this forum. Be sure to include in the text of your summary the names of all team members.

Some related readings:

• The Voyage of the Beagle, by Charles Darwin
• Darwin's Finches
• Adaptive Radiation of Darwin's Finches, in the American Scientist