<em>The similarity in their embryos and embryonic development suggests that reptiles, birds, and mammals share the same ancestor.</em>
Similarity in the structure and development of embryo is one of the evidences that is been used by scientists to support the theory of evolution of species. According to the theory of organic evolution, all organisms are on earth as a result of descent with modifications from common ancestors.
<u>Reptiles, birds, and mammals are all vertebrates. They share some basic characteristics and are thought to have shared a common ancestor before each group took different adaptive channels leading to their differences as they currently exist.</u>
When people lift weights, microscopic damage (microtears) occurs to the myofibrils within the muscle fiber. These microtears stimulate the body's repair response. ... The increased number of myofibrils causes muscle fibers to enlarge, increasing their volume and size.
