The popular theory is that the Ostrich buries its head in the 
sand, because if it can't see anything dangerous approaching, it feels 
safe.  Cartoonists depict it performing this action while standing up. 
    This is of course erroneous.  I have however seen an Ostrich 
sitting on its nest. The bird was a greyish female, and when it wished 
not to be noticed, it laid head and neck on the ground and was 
remarkably inconspicuous.  The grey-brown body made a small rock-like 
hump. I have also seen a sitting male Emu in the similar position on a 
nest.  The mixed grey and blackish body feathers successfully imitated a 
small boulder.  The head was usually doubled back on the neck, but when 
disturbed it stretched its neck and put its head down on the ground,  
and stayed like that until the threat had ceased to alarm it.
      When being transported in a truck or horse-float, domestic 
ratites are hooded by their owners by dropping a bag over the head.  
This keeps them calm and they don't try to jump out.
       Most myths about animals have some origin in fact.
Anthea Fleming
Val Curtis wrote:
Is this why the Ostrich is said to 'bury it's head in the sand'? I 
have often wondered where that saying originated. Is there any 
evidence of Ostriches (or Emus) burying their heads during extreme 
heat. Or do they do it during sand storms? Just wondering.
Val Curtis
Stephen Ambrose said:
 "Phillip Veerman is also correct in saying that some arid-zone bird 
species have short feathers or bare skin to increase convective heat 
loss. The most notable of these species in Australia is the Emu which 
has very short feathers and well-vascularised skin on the head and 
neck (known physiologically as heat or thermal window). In addition, 
it is important to recognise that the most important part of the body 
to keep cool is the brain.  The Emu is the bird species with the 
smallest brain relative to body size, its brain has a high 
surface-area to volume ratio and so it is adapted to losing more 
convective heat than a bird with a relatively smaller brain size. 
Interestingly, if emus are near a water source on a hot day they will 
splash water over their head and neck, which would result in 
evaporative cooling."
===============================
www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list, send the message:
unsubscribe (in the body of the message, with no Subject line)
to: 
===============================
  
===============================
www.birding-aus.org
birding-aus.blogspot.com
 To unsubscribe from this mailing list, 
send the message:
unsubscribe 
(in the body of the message, with no Subject line)
to: 
===============================
 
 |