In a first and introductory part the principles of phylogenetic tree construction (derived versus ancestral traits, mono-, para- and polyphyly) will be explained and applied in an exercise. Then we will discuss the major evolutionary lines of animal body plans, with particular attention to groups that were not discussed in "Bouwplannen Dieren" (BA1). A major theme is the contrast between traditional (morphology-based) views on phylogeny versus more recent insights (and controversies) based on molecular data. We will also briefly discuss some major evolutionary patterns such as evolution of segmentation, consequences of increase in body size, or adaptations to a parasitic lifestyle.
In the second part, by means of student presentations, we will discuss the characteristics of a number of small and/or less well known animal groups. Particular attention will be paid to to similarities and differences in body plans, and current hypotheses on evolutionary affinities of these groups.