Which biome features plants with thorns and small leaves adapted for dry conditions?

The biome characterized by plants with thorns and small leaves adapted for dry conditions is the chaparral. This biome often has a Mediterranean climate, characterized by hot, dry summers and mild, wet winters, which leads to the development of specific adaptations in plants.

In chaparral ecosystems, plants have evolved features such as small, thick leaves to reduce water loss through transpiration, and thorns or spines to deter herbivores. These adaptations are crucial in coping with the hot, dry conditions prevalent in this biome.

While the savanna also has some drought-resistant plants, it typically supports a mixture of grasses and scattered trees, and its adaptations are not as specialized for extreme dryness as those found in the chaparral. The tundra is known for its cold climate and permafrost, whereas the desert, while it does have plants adapted to dry conditions, usually features succulents rather than the shrubby characteristics of chaparral flora. Therefore, when looking for a biome strictly associated with the specified adaptations of thorns and small leaves for drought, the chaparral is the appropriate choice.