Graduate Research Course
Eagle Biophysics & Biochemistry
Accipitridae at the apex — 5× human visual acuity, 320 km/h dives, 12-cm harpy talons, and the recovery of the bald eagle from DDT. Nine detailed modules.
About This Course
Eagles are obligate aerial predators that have evolved a unique combination of high-acuity vision, raw grip force, and energy-efficient flight. The golden eagle (Aquila chrysaetos) stoops at 320 km/h. The Philippine eagle targets monkeys beneath forest canopy. The harpy eagle (Harpia harpyja) hoists 8-kg sloths from the trees with a 12-cm hallux talon. The African crowned eagle takes antelope 5× its body mass.
Cross-links: Climate M12 Amazon,Avian Biophysics,Migration Course,Feline Biophysics.
Key Equations
Lift Equation
\( L = \tfrac12 \rho v^2 S\, C_L \)
Wing Loading
\( W/S = m g / S \approx 7\text{--}10\,\text{kg/m}^2 \)
Minimum Power Speed
\( V_{mp} = \left(\frac{2mg}{\rho S}\right)^{1/2} C_L^{-1/2} \)
Visual Acuity (Reymond)
\( \alpha_{min} = 1.22 \frac{\lambda}{D_{pupil}} \)
Talon Grip Force
\( F_{grip} \propto M^{2/3} \)
Soaring Power Balance
\( \frac{dh}{dt} = w_{thermal} - \frac{D v}{mg} \)
Nine Modules
M0
Accipitriformes Evolution
60 Mya raptor radiation, Accipitridae vs. Falconiformes convergence, Aquila, Haliaeetus, Harpia genera, fossil forerunners, Jetz 2012 phylogeny.
M1
Flight Biomechanics
Lift/drag ratios 10:1+, golden eagle dynamic soaring to 320 km/h dive, wing loading 7-10 kg/m², Pennycuick flight mechanics, slotted primaries.
M2
Vision & Ultra-Fovea
Dual-fovea architecture, 5× human acuity, 4 cone types (UV sensitive), Reymond 1985 visual acuity, oil-droplet filtering, pecten oculi nutrition.
M3
Talon & Prey-Capture
Harpy eagle hallux 12 cm, grip strength 400-700 psi, talon locking mechanism, prey-mass scaling, Fowler 2009 talon morphometrics, African crowned eagle.
M4
Beak & Pellet Biochemistry
Hooked beak mechanics, digestive strategy, pellet formation (indigestibles), pH 1.5 gastric, urease-mediated N recycling, crop storage.
M5
Migration & Navigation
Steppe eagle & greater spotted eagle flyways, thermals-vs-flapping energetics, magnetic compass (cryptochrome), time-compensated sun compass.
M6
Sensory & Neurobiology
Wulst visual processing, hypertrophied optic tectum, motion-parallax neurons, head-stabilization kinematics, auditory lateralization.
M7
Reproduction & Eyrie
Eyrie thermal physics (aspect-choice), Cain & Abel siblicide, egg shell thickness, clutch size vs prey density, altricial development.
M8
Conservation (DDT, Lead)
DDT/DDE eggshell thinning (Ratcliffe 1967), bald eagle recovery post-1972 ban, lead ammunition poisoning (Pain 2019), wind-turbine strike, reintroductions.