1) If the fat is triglycerides, then a reasonable chemical formula is C51H140O6. Using only this fat, what will is the Respiratory Exchange Ratio (RER) of the bird when it is flying?

2) How many L of CO2 will it produce during its flight? (hint again, be careful about units!)

3. Finally, compare the weight specific cost of transport between this cockatiel and a walker/runner of similar mass (e.g. something like a chipmunk). BY WHAT FACTOR (I.e. how many times) is the walker/runner cost of transport larger than the minimum cost of transport of the flier (the cockatiel)? Its a lot energetically cheaper to fly!

Examine the curve above which is a measurement of the energy cost of flight in a 80.5 gram bird across several speeds Useful information: 1 mile =1609m 1 gram of H2O=1mlH2O Energy content of fat is 39.3kJ/gram and 2.0 L of O2 is consumed per gram of fat metabolized Kinetic energy =1/2mv2, work =FD gravitational potential energy =mgh, RER=CO2 produced per unit time /O2 consumed per unit time Efficiency=work out/energy in =25% for muscles Weight-specific cost of transport for walkers/runners =8.46M0.40 (where mass is entered as grams, and is expressed in units of mLO2 per gram of body tissue per kilometer) Flight speed (ms1)