Cactus and Euphorbia

Title Info
Common name Cactus; Euphorbia
Scientific name Cactaceae; Euphorbiaceae
Taxonomic group Caryophyllales; Malpighiales
Level FamilyFamily
Source Dan L. Perlman
Ecosystems Grasslands, savannas
Grasslands and savannas Tropical savanna
Selection and adaptations Selection
Selection Convergence; Morphology; Natural Selection
Lessons Water Relations
Date August 06, 2003
Location Near Wasso,Tanzania,Africa

Convergent evolution of cacti and euphorbs, Tanzania. The plant on the right of this image is clearly a cactus, and at first glance, the one on the left appears to be a different kind of cactus. It is, however, actually a euphorbia and not a close relative of the cacti at all. To deal with hot, dry climates, both species exhibit similar growth forms. They have thick succulent green stems that store water and perform photosynthesis, while having no leaves. Both have spines, as well. Although other euphorbias, such as the widely known Poinsettia, have broad leaves and are not succulent, this group has converged on the same morphology as the cacti.