Feather These barbules have minute hooks called barbicels for cross-attachment. Down feathers are fluffy because they lack barbicels, so the barbules float free of each other, allowing the down to trap air and provide excellent thermal insulation. At the base of the feather, the rachis expands to form the hollow tubular "calamus" (or quill) which inserts into a follicle in the skin. The basal part of the calamus is without vanes. This part is embedded within the skin follicle and has an opening at the base (proximal umbilicus) and a small opening on the side (distal umbilicus). Hatchling birds of some
Build-A-Bird Build-A-Bird Build-A-Bird (1986 or earlier) was educational software for the Unisys ICON II public school computer. It may have appeared on the ICON I or Unisys ICON III. Build-A-Bird was designed and developed by Ergonomics Lab, University of Toronto. Gameplay revolved around creating a bird by choosing from a selection of different body parts such as stork-like legs, short legs adapted to alighting on various natural surfaces, or predatory talons. Beak type and wing type were also among the changeable body part selections in Build-A-Bird. Upon selecting your preferred, various body part types the game would provide one or several