Correct Option
The correct option isRemaining in deep burrows during the day.
Explanation
Organisms in arid environments (deserts) face extreme temperature fluctuations and water scarcity. To survive, they employ physiological adaptations (internal metabolic adjustments) and behavioral adaptations (actions to avoid harsh conditions). Small animals, having a large surface area relative to their volume, are particularly vulnerable to rapid heat gain and water loss.
Option Analysis
- Development of thick fur for thermal insulation. is Incorrect: Thick fur is primarily an adaptation for cold environments to trap body heat (insulation). While some desert mammals (like camels) use fur to shield against solar radiation, small burrowing animals do not rely on thick fur as a primary mechanism for heat survival.
- Remaining in deep burrows during the day. is Correct: Desert lizards, snakes, and rodents (such as the Kangaroo rat) are often fossorial (burrowing) and nocturnal. By remaining in deep burrows during the day, they insulate themselves from the intense surface heat. The soil acts as a thermal buffer, keeping the burrow temperature significantly lower than the external environment.
- Profuse sweating to regulate body temperature. is Incorrect: Profuse sweating is a cooling mechanism that requires significant water loss. Since water conservation is critical in deserts, most desert animals lack sweat glands or minimize evaporative cooling to prevent dehydration.
- Seasonal migration to aquatic environments. is Incorrect: Seasonal migration to aquatic environments is not a standard adaptation for desert reptiles or rodents. They are adapted to survive in situ through water conservation techniques (e.g., concentrating urine) and heat avoidance.
Key Takeaway: Small desert animals primarily rely on behavioral adaptations, such as burrowing and nocturnal activity, to escape daytime heat, whereas physiological adaptations focus on water conservation (e.g., solid urine).