Mountain Ranges

Definition

Mountain ranges are elongated chains of mountains formed through tectonic processes, which can significantly influence climate, ecosystems, and species distribution. These geological formations act as barriers to dispersal, affecting the movement of species and gene flow across different regions. Furthermore, they often serve as refugia during climatic changes, providing habitats that support biodiversity in varying conditions.

5 Must Know Facts For Your Next Test

1. Mountain ranges can create significant climatic differences between their windward and leeward sides, leading to diverse ecosystems and varying levels of precipitation.
2. They can act as natural barriers that restrict the movement of species, causing isolation and promoting speciation over time.
3. During glacial periods in the Quaternary, mountain ranges often provided refugia for plant and animal species, allowing them to survive in cooler climates.
4. The uplift and formation of mountain ranges are closely linked to processes like plate tectonics, which continue to shape the Earth's surface.
5. Mountain ranges are hotspots for biodiversity due to their varied elevations and climates, supporting unique flora and fauna adapted to specific environmental conditions.

Review Questions

• How do mountain ranges function as barriers to dispersal for various species?
  • Mountain ranges create physical obstacles that can prevent species from moving between different habitats. This isolation can lead to reduced gene flow among populations, resulting in increased speciation as organisms adapt to their unique environments. The different climatic conditions on either side of a range can also encourage divergent evolutionary paths for species adapted to those specific settings.
• Discuss the role of mountain ranges as refugia during climatic fluctuations in the Quaternary period.
  • During the Quaternary period, significant climatic shifts occurred, which threatened many species' survival. Mountain ranges served as refugia by providing stable microclimates where certain plants and animals could persist despite harsher conditions elsewhere. These elevated regions often retained moisture and moderate temperatures, allowing biodiversity to thrive even during periods of extreme cold or aridity.
• Evaluate the impact of mountain range formation on ecosystem diversity and species distribution over geological time.
  • The formation of mountain ranges significantly influences ecosystem diversity by creating varied habitats across different elevations and climates. Over geological time, these ranges have shaped patterns of species distribution by acting as barriers or corridors for movement. As a result, they have contributed to both diversification through isolation and the maintenance of unique ecosystems that harbor specialized species adapted to specific niches along the gradients created by elevation changes.

Related terms

Tectonic Plates: Large sections of the Earth's lithosphere that move and interact at their boundaries, leading to the formation of mountain ranges through processes like subduction and continental collision.

Ecosystem Fragmentation: The process by which habitat loss and barriers like mountain ranges lead to the division of larger habitats into smaller, isolated sections, impacting species survival and diversity.

Refugia:

Areas that remain relatively unaffected by climatic changes, providing a stable environment where species can survive during adverse conditions.