Strong hooves adapted for climbing rocky terrain.
Explanation
Animals inhabiting specific ecological niches evolve physiological and morphological adaptations to survive environmental challenges. Mountain goats (Oreamnos americanus) inhabit steep, rocky, and often icy alpine environments, requiring specialized adaptations for locomotion and stability.
Option Analysis:
- Streamlined body for aquatic movement. is incorrect: A streamlined body is a hydrodynamic adaptation found in aquatic animals (e.g., fish, dolphins) to reduce resistance while moving through water. It is not relevant to terrestrial mountain environments.
- Strong hooves adapted for climbing rocky terrain. is correct: Mountain goats possess specialized cloven hooves with two spreadable toes that improve balance. The hooves feature a hard outer shell for digging into ledges and a soft, rubbery inner pad that provides traction on smooth or steep rock surfaces. This adaptation is critical for climbing vertical terrain to evade predators and access food.
- Adipose hump for food storage. is incorrect: An adipose (fat) hump is a characteristic adaptation of animals in arid or desert environments (e.g., camels, Zebu cattle) to store energy and metabolic water. Mountain goats store fat subcutaneously for insulation against cold, not in a dorsal hump.
- Elongated limbs for heat dissipation. is incorrect: Elongated limbs to facilitate heat dissipation are typical of animals in hot climates (following Allen’s Rule). Conversely, animals in cold mountain habitats tend to have shorter, sturdier limbs to conserve body heat and lower their center of gravity for stability.
Key Takeaway:
Mountain goats are adapted to high-altitude, precipitous terrain primarily through specialized hooves containing a hard outer edge and a soft inner pad, ensuring grip and stability on rocky surfaces.