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.
Conclusion: speciation is likely to have happened in very different modes. The evidence also says that speciation events occur quickly in relation to the average life of a species. This scenario for punctuated equilibrium is not always true, however (see below), so we have to ask how often it is true.