Bluejay writes:
In time, we may have the database and the computer and statistical tools necessary to analyze organisms as clades, rather than as species; but the complexity of that sort of system would make it statistically and logistically very unwieldy.
In theory every organism is biologically unique, having one or more novel mutations. These mutations may be more or less influential but there is no clear distinction of how many is required to make them "different". They are either identical or not.
Groupings of organisms are therefore always going to be based on an arbitrary criteria. The only caveat I can see is if we were to encounter an organism that doesn't share common descent.
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