Evolution
This is an excerpt from the paper...
Evolution is a process of change and development as organisms adapt to their environment and to changing circumstance through time. A variety of mechanisms have been identified as being involved in the process of evolution. This process does not take place in a steady and even manner, and eras of massive change have been identified in the fossil record during which a process called radiation has taken place, producing many new species and so many changes in a given population. Such a sudden and massive expansion of species has been identified in different parts of the world, such as the rapid growth in diversity of cichild fish in Lake Victoria in eastern Africa, where more than 500 species have evolved over the last 12,000 years. Scientists have sought to discover why such radiations occur. Darwin explained the process of specialization and related it to adaptation. Specialization is the adaptation of a body part to a particular function or of a whole organism to a particular environment, and much of the diversity of life is expressed through specialization. Organisms are specialized in order to perform certain tasks in response to environmental conditions. Those organisms able to adapt to changing conditions and to develop a new functional use for an organ or body part will survive better than those that do not make such adaptation. The adaptation can be singular and minor or can involve the entire organism as it changes from one function or environment to anothe
. . .
g into a range of new forms. This was seen as a representation of certain macroevolutionary events and enabled evolutionary biologists to study such miniature adaptive radiations for clues to what drives them in nature. This was accomplished by Paul Rainey of Oxford University and his colleague Michael Travisano. They placed Pseudomonas fluorescens, a common aerobic bacterium that thrives in the soil as well as on plants, in the unfamiliar habitat of a broth filled vial. They noted that this vial offered a variety of environments, all differing in the amount of available oxygen because oxygen varied with depth in the broth. After five days, the original ancestor had undergone rapid morphological change and had given rise to numerous new forms, each one presumably adapted to a specific niche in the vial (Morell, 1997).
Species radiation has been observed in different species in different environments on earth, and attempts have been made to replicate radiation to show what forces are at work in the process. A recent report on the adaptive radiations of island lizards in the Greater Antilles suggests that adaptive radiation may have similar results in similar environments. This is counter to the theory of historical con
. . .
Some common words found in the essay are:
Holm Parnell, Lake Victoria, Michael Travisano, University Cincinnati, Cracraft Eldredge, , Queiroz Rodriguez-Schettino, Evolutionary Biology, United Scientists, Discover Magazine, adaptive radiation, adaptive radiations, radiation found, morell 1997, adaptive radiation found, ehrlich holm parnell, ehrlich holm, parnell 1974, eldredge 1985, holm parnell, island lizards, darwin 1964, holm parnell 1974, de queiroz rodriguez-schettino, larson de queiroz,
Approximate Word count = 1882
Approximate Pages = 8 (250 words per page)
|
Customer Service
to Over
32,000 Professionally Written Papers!!!
