How are the Andes a barrier?

The Andes Mountains act as a significant barrier by creating challenging geographical conditions that affect climate, wildlife, and human movement. Their high peaks and rugged terrain obstruct moisture-laden winds, leading to distinct weather patterns on either side, such as arid conditions on the eastern slopes while promoting lush environments on the western side. This division also impacts flora and fauna, resulting in diverse ecosystems that differ on each slope. Additionally, the mountains can hinder transportation and communication, isolating communities and influencing cultural and economic interactions.