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The real genus problem



But seriously, the problem of the genus is a serious one that is receiving 
hardly any examination in the technical literature. Just saying that we 
should settle on traditional assignments and not worry too much about it is 
dubious because the genus continues to be used as a means of comparing 
diversity 
over place and time in technical papers examining evolutionary, extinction, 
paleogeographic and other items, as well as between groups of organisms. 
Such comparisons reflect reality only if genera provide a reasonably 
consistent measure of gradistic diversity. At this time they do not. The dozens 
of 
species highly diverse recent and extant Varanidae consists of one genus 
(Megalania recently being formerly and properly sunk into Varanus since it was 
nothing more than an oversized goanna and nothing makes it particularly 
special vis-à-vis the other varanid species whose size range is enormous 
regardless). The genus is under active research (genetics indicates the old 
subgenera 
are probably bogus) and there is no attempt to split it. Canis has a lot of 
species with substantial anatomical divergence, as do Panthera and Felis. 
There is tremendous variation within Homo. On the other hand Saurornithoides 
mongoliensis and junior were just generically split even though they show 
much less variation than is present in Canis or Varanus. The highly uniform 
hypacrosaur lambeosaurines are split into a number of genera even thought he 
morphological variation is largely limited to cranial features characteristic 
of species identifiers. Same for centrosaurines and chasmosaurs. 

Something has to be done about the situation. Seriously, the current 
sloppiness is scientifically dysfunctional and embarrassing. Either stop using 
genera to measure diversity although it is not clear what the alternative is 
(this can include making genera monospecific although that seems unlikely and 
may not be practical), or make genera more uniform as I am trying to do by 
lumping some overly relatively split genera and splitting up the fewer number 
that are overlumped (as per Iguanodon), although this too involves 
practical problems.  

GSPaul  
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