The evolutionary relationships and heredity of a group of organisms is called its phylogeny. Phylogenetic studies attempt to discover phylogenies. The basic approach is to use similarities based on shared inheritance to determine relationships. As an example, species of Pereskia are trees or bushes with prominent leaves. They do not obviously resemble a typical leafless cactus such as an Echinocactus. However, both Pereskia and Echinocactus have spines produced from areoles (highly specialised pad-like structures) suggesting that the two genera are indeed related. COUNT 4
QSN1 What does the phylogeny of a group represent? ANS1 relationships and heredity QSN2 How are the relationships within the group determined? ANS2 shared inheritance QSN3 What would be an indication of a shared inheritance in two cacti? ANS3 spines produced from areoles QSN4 What are areoles? ANS4 pad-like structures