AASAGACITY.NET
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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
 

Assuming a rate of divergence in mt DNA of 1.6–2.0% per million years. (Fleischer
et al. 1998; also see Lovette 2004; Ho 2007; Weir and Schluter 2008).

 

From mtDNA analysis, species take from between 0.2 to 5.5m yrs.  ("The Speciation & Biogeography of Birds", Ian Newton, 2003.

Total points sp
or
subsp

Scoring 0-1-2-3 0-1-2-3 0-1-2-3 0-1-2-3-4 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 mtDNA and other genetic 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, or successful breeding is not known to occur where there is breeding overlap.


Physical characteristics a little different



Physical characteristics noticeably different.



Physical characteristics very different.


Physical characteristics 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 definitely measurable.



Genetic differences indicate larger divergences.

Genetic differences are large enough to probably have non-viable offspring.


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




Petrels & Shearwaters
Comparison of a universally accepted species with another taxon, or other taxa such as subspecies
 Geographic separation/Chance
of cross-breeding

Physical differences
Voice

Song/Calls

Habitat preference

Behaviour
differences

Genetic differences

Total Points
sp
or
subsp
Puffinus carneipes Flesh-footed Shearwater
Puffinus c. creatopus Pink-footed Shearwater
Conclusion -

These two taxa are clearly of one species. They both winter in the Northern Pacific and could possibly migrate to each other's summer habitats; the physical differences are mainly the colours of the feather tracts; there is only a 0.70% difference in the mtDNA of the taxa. carneipes (Gould 1844) takes priority.

Macronectes giganteus Southern Giant Petrel
Macronectes halli Northern Giant Petrel
Conclusion -
In spite of the mtDNA difference between these two taxa of 0.61% and limited interbreeding (<1.5% at South Georgia), they seem to be two species. ("The Speciation & Geography of Birds",Ian Newton, p245). Breeding times, even on the same island are 6 weeks apart (halli breeding starts mid-August, giganteus starts in October) and feeding areas of each tend to be north of their breeding grounds, halli, or south, giganteus.

Fulmarus glacialis Atlantic Fulmar
Fulmarus rodgersii  Pacific Fulmar
Fulmarus glacialoides Antarctic Fulmar
Conclusion -
Firsty, there is a presumption here that glacialoides has a genetic difference score of 2 as ?no genetic work has been done on it. But glacialis and rodgersii  have a mtDNA difference of 1.92% due, no doubt, to the fact that the formation of the Artic ice sheet dividing the taxa about 3 million years ago although the eastern ice sheet (north of Siberia) may have melted more than once, since.
Thanks to Steve Howell who, in 2004, reviewed seabird papers by Penhallurick et Wink, & Austin et al., where the Fulmar split and the Shearwater lump originated from. We are indebted to you all.
0
2







0
1









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2
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0
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0
1
1
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0
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0
0
0
0
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0
1-2









0
0
0
0
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0
1-2









0
0
0

0
1







0
1









0
2
2?

0
4







0
4-6









0
5
5
sp
subsp







sp

sp









sp

sp
sp