Convergent evolution is a situation whereby different unrelated species independently develop similar traits. In some biological cases, other organisms develop identical characteristics to solve a common problem presented by their habitat (Sackton & Clark, 2019). When two or more organisms portray similar traits not inherited from a shared ancestor, they have undergone convergent evolution. A good example of convergent evolution is evident in sharks and dolphins. These two marine animals are of different origins, but their physical appearance is similar in that one can easily be mistaken for the other. Sharks are classified under cartilaginous fish, while dolphins are mammals. However, the animals separately evolved to develop similar physical features, which helped them easily survive in water and succeed in living as marine predators.
On the other hand, analogous structures often result from convergent evolution. They are similar structures or features found in different species. Such features are not identical in their system but perform the same function in other organisms. Analogous arrangements do not evolve from common ancestry as most species develop due to an existing environmental challenge. The features found in poinsettia and cacti plants are good examples of analogous structures. The two plants are of different origins, but both grow in desert environments (Sackton & Clark, 2019). The challenge of water shortage in the desserts influenced these plants to develop features such as thick and round leaves to aid in water conservation. This aids in their survival, especially in dry seasons where they utilize the stored minerals. Cacti plants have spines while poinsettias have thorns and the two different parts serve the same purpose in the two plants. Therefore, convergent evolution results in the development of analogous structures in other species.
Reference
Sackton, B.T., & Clark, N. (2019). Convergent Evolution in the Genomics Era: New Insights and Directions. The Royal Society Journal, 1(1). Web.