This is an amazing discussion. The problem is colour is a psychological
phenomenon that occurs in human brains not birds eyes. Colour depends on light
conditions and the state of the eye and brain of the watcher. The leaves on my
tree this morning changed from black to dark green to grey green and are now
yellow as the light changed. The subjectivity of colour was well known to the
ancient greeks who, so I read, had only three terms for "colour" - light, dark
and red. (Not sure if that is true but it sounds good).
Photographs, like paintings, are images, not birds, and present their own
problems. They are patterns of silver salts and dyes on paper or phosphor glows
on screens. The patterns depend on how cameras are set up and what and how much
processing is done. And quite a lot gets done, whether by the photographer to
produce a good print or by the camera without you knowing. Consistency in
photographic outputs is likely more a phenomenon of technology and the artistic
bent of the photographer than the subjects themselves. Brilliant photographers
work to get brilliant pictures. Photos of birds as we actually see them in the
field would not be so nice to look. The sumptuous photo with the lovely blue
eye that we saw a few days ago was a beautiful image done by a top
photographer, but I rarely (never) see birds so pristine and sparkling - like
they have been to the laundry.
Even in examining museum skins the perceived colour of feathers depends upon
the rooms lighting - flourescent, incandescent or LEDs, colour temperature,
reflectivity of surrounding surfaces etc. and how tired the observer is.
Dick’s approach is totally logical. Count the frequency of different perceived
colours in live birds in the field, dead birds and live birds in the hand over
a range of observers. The eye colour statement then becomes “most observers of
live birds see the iris colour as x, sometimes, y and rarely z” etc.
I am sure this dicsussion will continue to entertain. Please keep the photos
coming.
Cheers
Francis Crome
Francis Crome Pty Ltd
PO Box 107
Kallista
Vic 3791
Australia
+61 4 1773 0291 (M)
> On 3 May 2018, at 15:40, Ross Macfarlane (TPG) <> wrote:
>
> Actually, if Dooley's listening, someone should write this whole discussion
> up and publish a version of it in an upcoming Birdlife magazine.
>
> -----Original Message-----
> From: Birding-Aus <> On Behalf Of
> Geoffrey Dabb
> Sent: Thursday, 3 May 2018 10:49 AM
> To:
> Subject: [Birding-Aus] FW: Scrubwrens
>
> Some might have missed part of the puzzle. The below message from Dick
> Schodde was copied to list but I think only went to personal addressees.
>
> Geoffrey
>
> -----Original Message-----
> From:
> Sent: Tuesday, 1 May 2018 10:06 PM
> To: Geoff Shannon; Graeme Chapman; Mike Carter
> Cc: ; Stephen Ambrose; Geoffrey Dabb
> Subject: Re: [Birding-Aus] Scrubwrens
>
> Colleagues,
>
> I have been reading the exchange of emails on scrub-wren eye colour, and
> think that Stephen Ambrose's hypotheses have value. I have also just spoken
> with Graeme Chapmen on the phone.
>
> So I'll share with you all recorded iris colours on scrubwrens in the ANWC
> from relevant areas:
>
> Mt Lofty Range. Adult-plumaged males (n=7): cream (3), mid cream (2),
> cream-buff, cream-ivory. Adult-plumaged females (n=5): cream (2), mid cream,
> cream-buff, yellow. No juveniles.
>
> Kangaroo Island. Adult-plumaged males (n=5): pale yellow, pale straw, straw,
> pale grey-brown (probably subadult), pale cream-grey. Adult plumaged females
> (n=4): pale grey (2), pale grey-brown (probably subadult), pale buff. No
> juveniles.
>
> Wet forested southwest corner of WA. Adult-plumaged males (n=7): cream (2),
> creamy-white, creamy-grey, greyish cream, pale greyish cream, mid brown
> (probably subadult). Adult-plumaged females (n=2): pale cream-grey (2).
> Juveniles,(by plumage (n=4): creamy-white, dirty cream, mid cream, mid
> creamy grey.
>
> Shark Bay/Houtman Abrolohos: Adult-plumaged males (n=3): off-white
> (Abrolhos, 1), light green (Shark Bay, 2). Adult -plumaged females (n=5):
> off-white (Abrolhos, 4), light green (Shark Bay).
>
> Now there is subjectivity of colour interpretation by different collectors
> here and probable bias from dulling (darkening?) of irides between time of
> collection and its recording on the specimen bench in the field. Nonetheless
> it also shows that the issue is complex and that a more extensive
> photographic record is needed before we can be certain of regional
> differentiation in iris colour. Those photographs that are available I
> accept as accurate. I also think it likely that the descriptor "grey" in
> irides quoted above refer to the "blue" irides Graeme has been talking
> about. These, from their photographs, I would interpret as pale bluish white
> or pale blue-gray white, the same colour as the peri-orbital skin of Cacatua
> triton (galerita superspecies) in New Guinea.
>
> Cheers,
>
> Dick
>
> -----Original Message-----
> From: Birding-Aus On Behalf Of
> Stephen Ambrose
> Sent: Thursday, 3 May 2018 10:28 AM
> To: 'Ross Macfarlane (TPG)';
> Subject: Re: [Birding-Aus] Scrubwrens
>
> I think this discussion has demonstrated the value of everybody's
> contributions. Each contribution (observation/record/anecdote) is a piece of
> the jigsaw puzzle and there have been lots of people helping to assemble it.
> It's great that Birding-aus is the table in which the jigsaw puzzle is being
> assembled. A triumph for the internet, birdwatchers, photographers, citizen
> scientists, professional scientists, and (of course) the birds in question.
>
> Long may those contributions and Birding-aus continue.
>
> Cheers,
> Stephen
>
> Stephen Ambrose
> Ryde NSW
>
>
> -----Original Message-----
> From: Birding-Aus On Behalf Of
> Ross Macfarlane (TPG)
> Sent: Wednesday, May 2, 2018 2:03 PM
> To:
> Subject: Re: [Birding-Aus] Scrubwrens
>
> Agreed. An absolutely fascinating discussion on the minutiae of evolution in
> a single genus of one of our favourite LBJs...
>
> -----Original Message-----
> From: Birding-Aus <> On Behalf Of Alan
> Gillanders
> Sent: Wednesday, 2 May 2018 9:44 AM
> To:
> Subject: Re: [Birding-Aus] Scrubwrens
>
> Hear Hear.
> Thanks everybody.
> Alan
>
> On 2/05/2018 9:22 AM, Lawrie Conole wrote:
>> the conversation has been illuminating and conducted with goodwill and
>> civility
>
>
>
>
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