In a message dated 5/28/2006 8:27:34 PM Eastern Daylight Time, [EMAIL PROTECTED] writes:
> (1) virus ( ) alive ( ) not alive. > > (2) BSE prion ( ) alive ( ) not alive. > > (Choose one and only one answer to each question.) > > > The problem with this sort of argurement is that it assumes that are "essential" features that if discovered will allow for accurate catogorization. But "essences" are human intellectual inventions that however useful in dealing with the world do not reflect the reality of the world. Prior to Darwin biology was an essentalist field. Scientists and the public alike assumed that each species was a unique essential thing that could not be changed into another unique thing; each had its own indvidual creation by god. Darwin changed all that (According to Ernst Mahr this was his crowning intellelectual achievement). So we now know that species are created continously from their forebearers and that there is no specific time when a subspecies may be considered a species. Ring species pose a particular problem to any definition of species. A ring species variers continuously along its geographic distribution with each subspecies able to breed with nearby groups. Howvever where the ends of the rings come into contact (around the world in some cases- around a geographic barrier like a cannon in others) the two groups cannot interbreed. If one is hung up on esssences this is a problem but if one sees the natural non-essential continuim of things this becomes an expected outcome. The same is true for viral particles and prions. They have some features of living systems and lack otherrs. Call them whatever you want. _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l
