Question

A) Explain how geography, mass extinctions and adaptive radiation help explain the diversity of living organisms. B) Explain how changes in development can explain the evolution of new live forms. .Using the information you presented about geography, mass extinction, adaptive radiation and embryonic development, from the previous two questions, explain how living organisms evolve.

Answer 1

1A. ANS: During the cource of evolution or for the process of species diversity adaptive radiation, continental drift, and Extinction has been responsible. In the period of mass extinctions several species are vanised from the environment, but few are survived through the process of adaptive radiation. Since the masses separated, the organisms preexisting on those masses, who managed and adapted according to the needs and environment of those separated masses, thus resulting in diversification and adaption.

1B. ANS: Changes in development can lead to new live forms through adaptive radiation. With this, new species evolve. For example, Darwin's finches. On the island Galapagos, Darwin's finches developed such that there were changes in their size, shape and morphology of their beaks as they were distributed throughout the island. Since, the species did not develop through sympatry, there developed more than 7 species that inhabited the island.

2. ANS: Evolution is an ongoing, changing process, and over time unfavorable characteristics of a living organism are changed to better benefit that organism. By tracking the disappearance of imperfections (unfavorable traits) of an organism, one can witness the process of evolution.

Ex: Originally giraffes had short necks like zebras and horses, but as the shorter plant life was harder to obtain because of competition. So the giraffes with longer necks were at an advantage, and those who were normal with short necks starved to death before they could reproduce and pass on the short neck trait. In this way, the long neck "mistake" or mutation was passed on and the species evolved to having extremely long necks.
Other examples include the recessive trait for 5 fingers rather than six, which is the less common one despite being dominant. Because humans need 5 fingers, and 6 is extra, this mutation to 1 less finger stayed with the species to the point that almost no one has 6 fingers these days.