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Navigation Galliformes 5 families 290 species Helmeted Guineafowl Megapodiidae, 21 species -- Australasia Malleefowl, South Australia Cracidae, Curassows, Guans, Chachalacas, 50 species Plain Chachalaca Phasianidae Pheasants, partridges, grouse, turkeys, Old World Quail, and guineafowl 177 species (64%) Currently there less than 100 Attwater’s Prairie Chickens left in the wild. They inhabit two separate grassy patches in Texas totaling 12,400 acres (5,018 hectares), the remnants of six million acres (2,428,114 hectares) of coastal prairie that supported as many as a million Attwater’s a century ago. The grouse were over hunted early and hit by habitat loss every year since. Numididae Vulturine Guineafowl Odontophoridae – New World Quail, 30 species Navigation 3 Ways to Navigate Pilotage visual reference to landmarks Distance-and-bearing AKA dead reckoning Distance-and-Bearing Gwinner’s European Warblers Bicoordinate navigation Bicoordinate Navigation 1. Where you are 2. Where you want to be 3. Direction from 1 to 2 Need a map and a compass Displacement studies Early proof Wales to Boston White-crowned Sparrow Baton Rouge 26 of 411 returned Laurel, MD 15 of 660 returned Female traveled 6379 km in 8.15 days Navigation ability improves with age in Starlings Perdeck’s Starlings (Box 13-2 Gill) Displaced from Holland to Switzerland Adults exhibited bicoordinate nav Immatures only general direction Immatures Adults Map and compass Sun Compass Gustav Kramer 1950 Sun compass Requires a clock Displacement Studies Birds possess a timecompensated Sun compass Star compass Franz & Eleanore Sauer 1955 Garden Warbler Star Compass Emlen’s Indigo Buntings Time-compensated star compass? Hypothesis 1 Birds orientates to a specific star Hypothesis 2 Birds orientate with reference to a fixed geometric pattern independent of time of night Magnetic compass Time their return to home loft How do they find their way? Can a blind pigeon home? Magnetic Compass Herring Gull chicks Other compasses? Cardiac Conditioning Cardiac Conditioning shows birds can detect • Polarized & ultraviolet Light • Atmospheric pressure changes as small as 10 mm water = 10 m Δ altitude • Infrasound 0.06 Hz (man 20-20K Hz) Ornithologists have found birds can set their compass to the sun, moon, or stars. They are also guided by the Earth's magnetic field. Some even home in on their destination using a finely tuned sense of smell. Such skills are thought to be innate—part of their genetic makeup. Increasingly, there is evidence that these navigational aids are replaced in older birds by more complex systems. These depend on seasoned migrants being able to learn from experience. New research, published this week in the Proceedings of the National Academy of Sciences, suggests birds do this by improving their long-term memory to map migration routes. The study was carried out by Claudia Mettke-Hofmann and Eberhard Gwinner at the Max Planck Research Centre for Ornithology in Andechs, Germany. They found that migratory garden warblers (Sylvia borin) are able to memorize and remember a particular feeding site for at least a year. Its close relative, the Sardinian warbler (Sylvia melanocephala momus), which is nonmigratory, wasn't able to retain this information for more than two weeks.