Treatment. There's currently no cure for Parkinson's disease, but treatments are available to help relieve the symptoms and maintain your quality of life. These treatments include: supportive therapies â such as physiotherapy ; medication ; surgery (for some people)
Reinforcement is a necessary requirement for both the parapatric and sympatric theories of speciation. It is the process by which a hybrid zone (an area of contact between different forms of a species) develops into a full species barrier.
Causes of speciation. Geographic isolation. In the fruit fly example, some fruit fly larvae were washed up on an island, and speciation started because populations were prevented from interbreeding by geographic isolation.