English and many other languages read from left to right and top to bottom. As a result, readers often expect summaries or conclusions on the right-hand side or bottom of a figure. This can lead to some mistaken conclusions. Consider the following phylogenetic tree describing the relationship between a few animal phyla.

Questions

1. All of these animals share a common ancestor, the first animal. Have all of these animals been evolving for the same amount of time?
2. What traits or abilities do some or all insects have that humans do not?
3. Which of the organisms on the tree is most closely related to humans?
4. Does switching the placement of starfish and humans change the information on the tree? Explain your answer.
5. Based on your answers to questions 1–4, explain why the statement in bold sounds right, but isn’t.

Transcribed Image Text:

[ va Human Sea star Insect Jellyfish Sponge