A temperate grassland and a tropical rain forest are both climax communities. What accounts
for the discrepancy in plant species in these 2 biomes?

Tropical rain forest

Explanation: Tropical rain forest covers the largest area of terrestrial biome. This biome has highest number of plant and animal species.

This has a variety of plant and animals that makes a rich biodiversity. This biome is a source of many pharmaceutical drugs. The biome can also be a source of wooden logs, various types of chemical compounds derived from the animal species and plant species as well.

This biome is a home for many of the animal and source of food as well.

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as the gila monster consumes the eggs or young of the desert cottontail and gambel's quail, thus its main food supply is only accessible for a restricted time duration every year. however, for this, the gila monsters exhibit three adaptations, which elevate their survival rate in the desert condition.  

first, is that they possess huge bodies, and can consume greater concentrations of food during a small period. secondly, they require to feed infrequently as they can accumulate fat in their tails. ultimately, their rate of metabolism is very low, so that they can burn their reservoirs of fat gradually.