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 real life birds that fit your selections. What happened next in the game involved educational material about your bird's range and habitat. The visual representations of the birds, their body parts and the bird habitats were in colour and vivid for the time but lacked animation. 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