Horned lizards use their horns primarily to defend themselves against which of the following?

• A. Predators such as birds and mammals
• B. Parasites and diseases
• C. Competition for mates
• D. Extreme temperatures

Answer: (A)

Verified step by step guidance

1. Understand the primary function of the horns in horned lizards. Horns are physical adaptations that serve as a defense mechanism.
2. Consider the types of threats that horned lizards face in their environment. These threats typically include predators, environmental factors, and competition.
3. Evaluate the options provided: (1) Predators such as birds and mammals, (2) Parasites and diseases, (3) Competition for mates, and (4) Extreme temperatures.
4. Analyze which of these threats would be effectively countered by the physical structure of horns. Horns are unlikely to combat parasites, diseases, or extreme temperatures directly, nor are they used in mate competition.
5. Conclude that the horns are most effective against predators, as they can deter or injure animals such as birds and mammals that pose a direct threat to the lizard's survival.