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Hi Everyone,
I came across an article noting that scientists at Johns Hopkins Medicine h=
ad uncovered the reasons why an owl can almost fully rotate its heads. I've=
pasted a summary of the article below with a link to the full article afte=
rward for those of you who are interested.
All the best,
Lance
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
After much research, scientists at John Hopkins University have determined =
how owls are able to rotate their heads up to 270 degrees without damaging =
their blood vessels.
Humans get whiplash from rapid, twisting head movements because that damage=
s the arteries supplying blood to the brain. Researchers have discovered fo=
ur special adaptations that keep owls from having a stroke every time they =
turn to watch potential prey.
Arterial Reservoirs
The scientists discovered that blood vessels at the base of owl's heads get=
larger and fill with blood as the head turns. These arteries are pooling b=
lood to minimize any interruptions in blood flow to the owl's brain and eye=
s. Human arteries, in comparison, remain small and do not increase in size =
as they branch out.
Larger Holes in Vertebrae
The holes in an owl's vertebrae are ten times the size of the arteries whic=
h run through them. The larger holes create cushioning air pockets which al=
lows for more flexibility and movement of the arteries, which prevents them=
from being damaged. This differs from human's vertebral holes, which hug t=
he arteries snugly.
Higher Artery Entrance
Owl's vertebral arteries were also found to enter the vertebrae higher up t=
han in most birds, entering the 12th vertebrae instead of the 14th. This gi=
ves the arteries more room and slack , which allows for greater movement.
Carotid and Vertebral Artery Connections
The vertebral and carotid arteries in owls contain small connections that a=
llow them to share blood between each other. This allows blood to be exchan=
ged in the event that one or the other is blocked, ensuring continuous bloo=
d flow to the owl's brain. There are only rare examples of this found in hu=
man anatomy.
According to the scientists, these four adaptations are what allow owls to =
turn their heads in such an extreme fashion without any adverse effects.
The team from John Hopkins had their findings acknowledged in the journal S=
cience February 1st as the winners of the National Science Foundation's 201=
2 International Science & Engineering Visualization Challenge.
http://www.hopkinsmedicine.org/news/media/releases/owl_mystery_unraveled_sc=
ientists_explain_how_bird_can_rotate_its_head_without_cutting_off_blood_sup=
ply_to_brain
--_000_92470D8023567B4D8D50FBA6E5E9D00F0DA084C036HCXMSP1calmco_
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<font face=3D"Calibri, sans-serif" size=3D"4">
<div>Hi Everyone,</div>
<div> </div>
<div>I came across an article noting that scientists at Johns Hopkins Medic=
ine had uncovered the reasons why an owl can almost fully rotate its heads.=
I’ve pasted a summary of the article below with a link to the full a=
rticle afterward for those of you who
are interested.</div>
<div> </div>
<div>All the best,</div>
<div> </div>
<div>Lance</div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2">=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D</font></div>
<div><font size=3D"2">After much research, scientists at John Hopkins Unive=
rsity have determined how owls are able to rotate their heads up to 270 deg=
rees without damaging their blood vessels.</font></div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2">Humans get whiplash from rapid, twisting head movemen=
ts because that damages the arteries supplying blood to the brain. Research=
ers have discovered four special adaptations that keep owls from having a s=
troke every time they turn to watch
potential prey.</font></div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2"><b>Arterial Reservoirs</b></font></div>
<div><font size=3D"2">The scientists discovered that blood vessels at the b=
ase of owl’s heads get larger and fill with blood as the head turns. =
These arteries are pooling blood to minimize any interruptions in blood flo=
w to the owl’s brain and eyes. Human arteries,
in comparison, remain small and do not increase in size as they branch out.=
</font></div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2"><b>Larger Holes in Vertebrae</b></font></div>
<div><font size=3D"2">The holes in an owl’s vertebrae are ten times t=
he size of the arteries which run through them. The larger holes create cus=
hioning air pockets which allows for more flexibility and movement of the a=
rteries, which prevents them from being
damaged. This differs from human’s vertebral holes, which hug the art=
eries snugly.</font></div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2"><b>Higher Artery Entrance</b></font></div>
<div><font size=3D"2">Owl’s vertebral arteries were also found to ent=
er the vertebrae higher up than in most birds, entering the 12th vertebrae =
instead of the 14th. This gives the arteries more room and slack , which al=
lows for greater movement.</font></div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2"><b>Carotid and Vertebral Artery Connections</b></font=
></div>
<div><font size=3D"2">The vertebral and carotid arteries in owls contain sm=
all connections that allow them to share blood between each other. This all=
ows blood to be exchanged in the event that one or the other is blocked, en=
suring continuous blood flow to the
owl’s brain. There are only rare examples of this found in human anat=
omy.</font></div>
<div><font size=3D"2"> </font></div>
<div><font size=3D"2">