Bird migration evidence. Seabirds fly low over water but gain altitude when crossing land, and the reverse pattern is seen in landbirds. However most bird migration is in the range of . Bird strike aviation records from the United States show most collisions occur below and almost none above . Bird migration is not limited to birds that can fly. Most species of penguin (Spheniscidae) migrate by swimming. These routes can cover over . Dusky grouse "Dendragapus obscurus" perform altitudinal migration mostly by walking. Emus "Dromaius novaehollandiae" in Australia have been observed to undertake long-distance movements on foot during droughts. While participating
Purple Songs Can Fly through Purple Songs Can Fly were burned on purple CDs and were then played on Continental Airlines flights. Purple Songs Can Fly Purple Songs Can Fly is a non-profit organization that sponsors a music program at the Texas Children's Cancer Center in Houston, Texas. It allows patients at the hospital to compose and record songs in a real studio. The program was founded in March 2006 by Anita Kruse, a songwriter and pianist. The Love Street Light Circus donated $10,000 to build a studio at the hospital. By January 2009, patients have recorded over 116 songs. According to David Poplack,