lecture 40 lecture - flightat flapping airspeed of 12.9...

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Lecture 40: Navigation and Orientation 1- Monarch Migratory Cycle 2- Fuel Use 3- Energy Savings 4- Direction – sun compass 5- Direction – Magnetic and Star Compass -Monarch butterfly (30 day life cycle, egg layed on milkweed plant, larva eats milkweed leaves, grows, sheds skin 3 x pua, adult…male and female look slightly different -like many temperate creatures, monarchs migrate south for the winter but it is not round trip …E No America fly to Mexico and return only to So US…individuals here in the summer are 3-4 generations descended from last year’s monarchs -@ winter roosts, monarch butterflies congregate by the millions -monarch butterfly winter roost sites are at high elevation where temperatures are low, but above freezing so metabolism is kept low which conserves energy -although metabolism is kept low @ low temps, they can dehydrate in dry hair and must drink water -late summer, monarchs begin lipid loading -50% water, 20% chitin, 23% lipids -monarch energy budget is unfavorable -flight metablism @ 22 degrees C and they get 9.4 kcal/g of lipid so 143 mg will buy about 12 h
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Unformatted text preview: flightat flapping airspeed of 12.9 km/h 157 km and if they flapped the entire way it would cost 3,627 mg -monarchs gain height with little energic cost from thermal lift and slope lift-they find their way by the sun compass morning: steer right of sun. .noon: steer at sun.afternoon: steer left of sun-spatial cues that bird uses but monarchs do not (magnetic field) sun is stronger than magnetic-some birds use a star compass vision through a compound eye is too low aculty for nocturnal insects to resolve individual stars-anabatic wind-solar azimuth-caloric content of fuel-celestial cue-clock shifting-gliding-glycogen-headwind-Helmhotz coil-learned landmarks-lipid loading-magnetic orientation -Michoacan-migratory restlessness-monarch butterfly-Monterey peninsula-orientational cue hierarchy-sham group -slope lift-star compass-tailwind-thermal lift-time compensated-triglycerides...
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