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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.