AASAGACITY.NET
  Knowledge is Empowering
A scoring system to define a species; an evaluation of a taxon/some taxa, using the Sensible Species Definition. 5 points between taxa makes a different species.



Geographic separation/Chance
of cross-breeding
Physical differences Voice

Song/Calls

Habitat preference
Behaviour
including
migration
Known
genetic
differences

Total Points
sp
or
subsp

Scoring 0-1-2-3 0-1-2-3 0-1-2-3 0-1-2-3 0-1-2-3 0-1-2-3-4-5

A SENSIBLE SPECIES DEFINITION (Anderson 1998 and 2012)
Species are populations that are interbreeding and which are reproductively isolated from other such populations by their reproductive isolating mechanisms.
These may include -
     geographic separation / chance of cross-breeding;
    morphological and plumage differences;
    voice;
    habitat preference;
    behavioural differences such as nest-building, social grouping or migration;
    consistent DNA differences.
Each mechanisms can be weighted according to the strength of difference from a recognised species and given a score between 0 and 5; a total of 5 would give the taxon species status.
0





1






2






3





4





5




Broad hybrid zone





e.g. Narrow and stable hybrid zone,
or good chance of interbreeding.



e.g A small chance of interbreeding.




No chance of interbreeding.

Feather tracts and/or bare parts a little different,


Feather tracts and/or bare parts noticeably different,


Feather tracts and/or bare
parts very different.


Feather tracts and/or bare
parts completely different.
Not so different voice range and/or song phrases.




Noticeably different voice range and/or song phrases,



Completely different voice range and/or song phrases.
Similar or slightly different habitat preferences.



Noticeably different habitats.








Completely different habitats.
Slightly different behaviour.






Noticeably different behaviour.







Very different behaviour.
Genetic differences are barely measurable.


Genetic differences are measurable.




Genetic differences are larger, or net nucleotide divergences are > say 3 %.
Genetic differences are large enough to probably have non-viable offspring.



Genetic differences are so great that viable inter-breeding would be impossible.




Ortalis spp
Comparison of an accepted species with other taxa such as a subspecies
 Geographic separation/Chance
of cross-breeding

Physical differences
Voice

Song/Calls

Habitat preference

Behaviour
differences

Genetic differences

Total Points
sp
or
subsp
Research -
Ortalis g. guttata         Speckled Chachalaca
                            Western Amazon, Eastern Brazil
Ortalis g. columbiana   Colombian Chachalaca
Ortalis m. araucuan      East Brazilian Chachalaca-EBrazil
Ortalis g. squamata      Scaled Chachalaca - SEBrazil
Conclusion -
If Ortalis guttata is a species then columbiana, araucuan, & squamata are sub-species.

Research -

Ortalis m. motmot         Variable(Little) Chachalaca
                          Amazon-Orinoco, other parts of Brazil               
Ortalis m. superciliaris  Buff-browed Chachalaca - NEBrazil
Ortalis m. ruficeps          Chestnut-headed Chachalaca
Conclusion -
superciliaris & ruficeps are sub-species of  Ortalis motmot.

Final comparison -
Ortalis motmot         Variable Chachalaca
Ortalis m. guttata         Speckled Chachalaca 
Final Conclusions -
Surprisingly, it can be seen that Ortalis motmot is the species, and includes guttata as a subspecies. However, if araucuan or squamata are found to have a genetic difference score indicating a nucleotide divergence of at least 0.5 million years from motmot and/or guttata, the South American chachalacas should be assessed again.  

Research -
Ortalis g. garrula          Chestnut-winged Chachalaca
Ortalis g. cinereiceps          Grey-headed Chachalaca
Conclusion -
There do not seem to be enough differences between these two taxa to make two reproductively isolated species.



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sp
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sp?







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subsp









sp

subsp