Wed, 20 Aug 2008 22:19:36 BST CiteULike: timothee Dimijian http://www.citeulike.org/user/timothee/author/Dimijian CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/timothee/article/1023164 <i>Proc (Bayl Univ Med Cent), Vol. 13, No. 3. (July 2000), pp. 217-226.</i><br /><br />Symbioses, prolonged associations between organisms often widely separated phylogenetically, are more common in biology than we once thought and have been neglected as a phenomenon worthy of study on its own merits. Extending along a dynamic continuum from antagonistic to cooperative and often involving elements of both antagonism and mutualism, symbioses involve pathogens, commensals, and mutualists interacting in myriad ways over the evolutionary history of the involved "partners." In this first of 2 parts, some remarkable examples of symbiosis will be explored, from the coral-algal symbiosis and nitrogen fixation to the great diversity of dietary specializations enabled by the gastrointestinal microbiota of animals. Evolving together: the biology of symbiosis, part 1. GG Dimijian Proc (Bayl Univ Med Cent), Vol. 13, No. 3. (July 2000), pp. 217-226. 2007-01-03T10:37:13-00:00 2000 Proc (Bayl Univ Med Cent) 0899-8280 13 3 217 226 ecology essay evolution parasitology symbiosis trade-off http://www.citeulike.org/user/timothee/article/1023163 <i>Proc (Bayl Univ Med Cent), Vol. 13, No. 4. (October 2000), pp. 381-390.</i><br /><br />Symbiotic trade-offs dominate the world of biology and medicine in colonist-host relationships and between separate, mutually dependent organisms of different species. Infectious and parasitic diseases can be better understood by exploring the dynamic continuum between pathogenicity and mutualism, between antagonism and cooperation-the sliding scale along which microorganisms can move in a moment's notice with a single nucleotide substitution. Organisms practicing piracy or pastoralism may be close genetic relatives. Mergers occur not only between cells but also between genomes; viruses co-opt host genes and in turn insert themselves into host genomes. Separate organisms, from ants to fungi to plants, establish symbiotic ties with each other that bind over deep time, generating much of the diversity we see in nature. Evolving together: the biology of symbiosis, part 2. GG Dimijian Proc (Bayl Univ Med Cent), Vol. 13, No. 4. (October 2000), pp. 381-390. 2007-01-03T10:36:50-00:00 2000 Proc (Bayl Univ Med Cent) 0899-8280 13 4 381 390 ecology essay evolution parasitology symbiosis trade-off