The Evolution and Ecology of Forests

Texas Tech scientists Sankar Chatterjee, John Zak, and Dylan Schwilk speak about the evolution and ecology of forests.

Caveat: Dr. Chatterjee's slideshow was not shared. Pardon the omission.

Thursday, September 24, 7:00 pm

• ‍Sankar Chatterjee, Geosciences, TTU, "The Origin and Evolution of Forests"‍
• John Zak, Biological Sciences, TTU, "The Fungal Ecology of Forests"‍
• Dylan Schwilk, Biological Sciences, TTU, "Fire and the Forest 'Sky Islands' of West Texas and the Southwest"‍

Moderator: Bruce Clarke

Summary

• Sankar Chatterjee discussed the origins of trees and forests over geological timescales. Land plants evolved from aquatic ancestors around 480 million years ago with the help of fungal symbionts. The first forests appeared around 380 million years ago. Flowering plants proliferated after the extinction of dinosaurs.
• John Zak explained the critical ecological role of fungi in forests. Fungi form mutualistic mycorrhizal relationships with plant roots, increasing nutrient and water uptake. Different types of mycorrhizal fungi dominate different forest biomes globally. Saprophytic fungi recycle nutrients by decomposing wood and litter.
• Dylan Schwilk discussed forest ecology in sky island mountain ranges of the desert Southwest. Forest distribution is influenced by climate, especially soil moisture, but also shaped by fire history. Drought stresses trees, while different tree species have varying adaptations to survive or resprout after fires.
• In discussion, the scientists emphasized how human activities like introducing invasive species, nitrogen pollution, and fire suppression have damaged forests worldwide. Indigenous burning practices sustained historic landscapes. Understanding long-term forest ecology and human impacts is key to sound future stewardship.

The scientists covered the deep history and complex ecology of forests, highlighting fungal symbioses and fire regimes. Human ignorance has often led to forest destruction, requiring new attitudes and policies for conservation.