Final answer:
Tracheid's provide water transport and mechanical strength to plants, enabling them to grow tall and compete effectively for sunlight and nutrients.
Step-by-step explanation:
The evolutionary importance of plant tissue composed of tracheid's is primarily that it provides water transport. Tracheids are a type of xylem cell with thick secondary walls that help transport water throughout the plant. The ability to efficiently conduct water and minerals absorbed from the soil up to the shoot is essential for plant survival and growth, particularly in terrestrial environments. Additionally, the cells' walls are reinforced with lignin, making them rigid. This rigidity provides mechanical strength to the plant, which enables it to grow taller and outcompete other plants for light and nutrients. However, while tracheid's contribute to rigidity and mechanical strength, they are not directly involved in photosynthesis.