Idea of tangles mass of vegetation, or jungle is incorrect, except along major rivers, where light reaches the forest floor. Otherwise, open ground layer. Lots of lianas , or woody vines. Lots of epiphytes , or air plants. Both are adaptations to permit plants to be in higher light of forest canopy.
Many trees are top-heavy, to reach into canopy light source.
Have buttresses at base for structural support. D. Highest diversity of plant and animal life on the planet occurs in tropical rain forests. Hundreds of different tree species on just a few acres of ground. Many canopy-dwelling birds, mammals, herps, insects. Annual precipitation totals decrease along this gradient 3.