Page 101 - The Origin of Birds and Flight

A
T
F
E
R

H
E

Y
P

T
O
F
E

E
C
S
P
I
C
I
F

R
V
S
E

A
E
S
A
H
T THAT EVERY TYPE OF FEATHER SERVES A SPECIFIC
R
E
T
E

Y
V
G
E
R
T
L
I
U
L
T
A
E
N
O
I
R
N
E
P PURPOSE IS A SIGN OF INTELLIGENT CREATION
C

T
S

I
G
S
E
I

S
A

N
P
O
F
I

O
N

In addition to flight, feathers have various other functions such as
in courtship display, insulation of body heat, and signaling. 1 Feathers
also provide significant protection against extreme weather conditions
such as cold wind and rain. Fitted one on top another like tiles, and
covered in a layer of oil, feathers protect the bird against water and
heat loss, in the same way that roof tiles protect a house.
The differences in the feather’s components—stalk, barbules, and
hooks— have also been specially created in line with their use.
Pennaceous feathers are bound with hooks to neighboring feathers to
form a tightly bound surface, a structure ideal for flight. In plumula-
ceous feathers, on the other hand, no stalk makes up the stem of the
feather. The feathers appear in bunches, an inflated structure that’s
ideal for heat insulation.
1) W. J. Bock, “Explanatory History of the Origin of
Feathers,” American Zoology, Vol. 40, 2000, p. 479.
Pennaceous
feather
Plumulaceous
feather