Ja, PETER,
og se alternative farver, halsplet m.m. på
HELGEs Inari foto d. 10 marts!
Ovenstående er en dunet hjerteknuser,
med LILLE-bitte øje og næb,
tilsyneladende (ligesom Elefantunger og Katte)
mest optaget af: Sig selv!
Tak ............. C.
Food for Thought ?
********************
Exciting that two small, extremely Northern,
mainly Non-migratory(!) passerines - i.e. the above
Grey-headed C. and Arctic Redpoll - have MINI,
pinhead-sized eyes,
compared to closely related species in temperate
zones, w/ wider eyes.
QUESTIONS :
# 1.
Similar feature in other Northern/(sub)arctic,
stationary or migratory, smaller passerine species?
# 2.
The winter season is quite DARK around the top
of the Earth.
So one miiiight expect LARGER eyes up there??
- i.e. like passerines living on shaded forest floors,
or Owls and Nightjars?
Any explanation or hypotheses on WHY some Northern
passerines got SMALLER eyes??
_______________________
P.S. for further stimulation:
Some arctic (original) HUMAN populations have less
open eyes, than populations further South.
SEALs have (appealing!) wide eyes, whereas WHALES - frequently hunting at extreme, DARK depths -
relatively, have MINI-eyes like Rhinos & Elefants.
NB: Members of Seal/Whale families operate in
both cold & warm waters.
_____________________________
Kindly feel free to speculate and comment.
Yours ............ C.
Carsten,
Lapmejsen øjne er ikke spor mindre end Sump-og Fyrremejsens.
Det er blot et optisk bedrag, hovedet ser nemlig større ud pga. de lange og fyldige fjer. En tilpasning til hårdt klima.
Jeg tror bestemt det samme gælder Gråsisken/Hvidsisken.
Mvh.
Peter
Interesting, as stated by PETER, that eyes of Grey-
headed C. are not smaller than those of Marsh and
Willow, but may appear so due to heavier plumage
(due to harsh climate) making Grey-headed's head
appear large, and eyes ('optically') smaller.
I may add that the diameter of the eye-ball of
Eskimo or Asian people is probably of the same size
as other people's with same cranium size.
But due to the socalled Mongolian (epicanthic) fold,
Asian eyes may appear narrower or smaller.
Thanks PETER ................ C.
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Smuk douce farvesymfoni i Birk, Mejse og Baggrund,
med fine detaljer:
1. Et stykke bag øjet rager Kalotten lidt ned
som en lille mørk spids.
Det er ikke alm. morgen 'uredelighed' men typisk
for Lap'pen,
- samme gælder den bagtil let opbulede kalot.
2. I den diffuse belysning, fremtræder det SORTE
parti fra næb henover øje med al tydelighed
- ligesom d. bredt udfoldede sorte halsklud.
Det Bitte øje i det Store hoved kan anes.
Tak, HELGE, for dette af og fra 'Nordkalotten'
VH.............. C.
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