Island Thrush (1 Viewer)

... and the same game again o

How many species in the poliocephalus complex ?

Voelker et al. 2007 say only one but … “Given the morphological diversity, disjunct nature of subspecies (islands), lack of migratory behavior and sequence variation, Turdus poliocephalus should arguably be split into multiple species.”

Peterson 2007 says “the biological species concept might recognize the 31 geographically contiguous plumage-type units, whereas the evolutionary and phylogenetic species concepts might best recognize all 38 of the distinct population units”.

Now if we listen to Jones & Kennedy 2008, they “suggest following the preliminary data of Peterson (2007) for prioritization of evolutionarily significant units (Moritz 1994) worthy of conservation attention.”
But they also say that some distinct populations are currently lacking formal subspecific names; in other words Peterson’s might further inflate his numbers.

So before we have a comprehensive molecular analysis on all populations and closely related taxa, there is still room for extrapolation ... and discussion.

Daniel

Having seen the probably most boring race (in Papua New Guinea), I wouldn't mind adding a stunner like the Taiwanese Island Thrush... The nominate is extinct, that might be a complication.
I think keeping this – obviously recently radiated – bird as one species because splitting it into many would complicate matters is rather ridiculous. But birds with a more conservative plumage should also be examined: the Gran Canaria Blue Chaffinch is a monophyletic taxon that is disappearing without anyone (seemingly) caring – everyone thinks it survives on Tenerife!

Nothing boring about thrushes. Ours are a plump and wonderful combination of subtle earthy grey and brown.

I must admit, after seeing T.poliocephalus taxa in Borneo, Taiwan and Fiji ( got a full house there ) the concept that they are all one species seems rather like making them / it a "species of convenience". If there was one complex that needs sorting out it's this one.
Chris