Varying Patterns of Speciation Essay -- Wallaces Line Plate Tectonics

Varying Patterns of Speciation Wallaces line, located in the Malay-Archipelago, is oneness of the best known and most studied boundaries of zoogeography in the world. It is a variety zone between the islands of Borneo and Sulawesi and the islands of Bali and Lombork, which marks both the convergence and division of the different flora and fauna found in the Asian (Borneo, The Philippines, and Western Indonesia), and the Australian regions (Sulawesi, Eastern Indonesia, Australia, and New Guinea) (Schulte 2003). The sibyllic line was first proposed by Alfred Russel Wallace in 1858 after observing many morphological differences of various bird species in the Asian and Australian regions (Raven 1935). In the past, to confirm the placement of Wallaces hypothetical line, researchers stir applied the theories of plate tectonics and continental drift in order to create geographical reconstructions of land masses. From this information, researchers were able to substantiate a majorit y of the boundaries of the originally drawn line. Presently, however, due to the enigmas found on the island of Sulawesi, a portion of the line between Borneo and Sulawesi (Celebes) still remains uncertain (Whitmore 1981). Researchers have identified two genera that contradict the location of the line the macaque monkey (Macaca species) and the Sulawesi anuran (Bufa celebensis) (Evans et al. 1998). Whereas geographical phenomena such as tectonic plate shifts, rising and go sea levels, and climatic fluctuations have caused the morphology of the Sulawesi toad to remain plumb undifferentiated, the ancestral macaque monkeys have evolved into seven distinct endemic species.The zoogeography on the eastern and western sides of Wallaces line... ...esi. Evolution. 5761436-1443.Evans, Ben J., Juan Carlos Morales, Jatna Supriatna, and Don J. Melnick. 1998. Origin of the Sulawesi Macaques (Cercopithecidae Macaca) as Suggested by mitochondrial DNA phylogeny. Biological Journal of the Lin nean Society. 66539-560.Michaux, B. realm Movements and animal distributions in east Wallacea (eastern Indonesia, Papua New Guinea and Melanesia). Palaeogeography, Palaeoclimatology, Palaeoecology. 112323-343.Raven, Henry C. 1935. Wallaces Line and the Distribution of Indo-Australian Mammals. New York.Schulte, James A. II. Jane Melville, and Allan Larson. 2003. Molecular phylogenetic manifest for ancient divergence of lizard taxa on either side of Wallaces Line. The Royal Society. 270597-603.Whitmore, T.C. 1981. Wallaces Line and Plate Tectonics. Clarendon Press. Oxford University Press, New York.