These diagnostic nodes typically occur only at distal portions of the barbules
, but there are consistent differences in the locations of these triangular-shaped nodes on barbules
for some groups of waterfowl (Dove and Agreda, 2007).
and the alignment of melanosomes within them, Carney said, are identical to those found in modern birds.
Ground in a pestle, the kingfisher's feathers are dark brown, similar to ravens; contour feathers have a tiny turquoise spot at the tip and colourless barbules
to trick the light and scatter the blue-green wavelengths.
Cell structure of developing barbs and barbules
in down feathers of the chick: Central role of barb ridge morphogenesis for the evolution of feathers.
Histologically, barbs are formed by a mid-axial part called ramus from which barbules
His beak reseals the barbules
by zipping them together.'
In turn, hundreds of barbules
project from each barb.
And if there are differences in effectiveness, can we determine as Barbules
and Callister (2000) put the challenge: "Which technologies have educational potential for which students, for which subject matters, and for which purposes?" In other words, is there an optimal match possible between student, learning and technology?
Each barb has thousands of smaller barbules
that project toward adjacent barbs.
Their wings are rudimentary, and their feathers lack barbules
, which is why they look like hairs.
It gets it's name from the four barbules
around its mouth which it uses for finding its food on the river bed.