Pangaea breakup

Definition

The Pangaea breakup refers to the geological process during the Mesozoic Era when the supercontinent Pangaea began to split into separate continents approximately 175 million years ago. This division led to significant changes in global climate, ocean circulation, and the distribution of flora and fauna, influencing ancient biogeographical patterns across the planet.

5 Must Know Facts For Your Next Test

1. The breakup of Pangaea led to the formation of two major landmasses: Laurasia in the northern hemisphere and Gondwana in the southern hemisphere.
2. As continents separated, isolated populations of plants and animals evolved independently, leading to increased biodiversity.
3. The Pangaea breakup significantly altered ocean currents and climate patterns, impacting global temperatures and rainfall distribution.
4. Fossil evidence shows that species such as Mesosaurus were found in both South America and Africa, supporting the idea that these continents were once connected.
5. The timing and process of the Pangaea breakup played a crucial role in shaping the modern distribution of species, contributing to patterns of endemism and extinction.

Review Questions

• How did the breakup of Pangaea influence ancient biogeographical patterns across different regions?
  • The breakup of Pangaea created barriers between landmasses, leading to geographic isolation for many species. This isolation allowed populations to evolve independently, resulting in distinct species developing on different continents. As a result, ancient biogeographical patterns emerged where similar habitats on separate continents housed unique species adapted to their environments, ultimately shaping biodiversity as we know it today.
• Discuss how plate tectonics is related to the concept of the Pangaea breakup and its implications for modern ecosystems.
  • Plate tectonics provides the framework for understanding the movement of continents, including the breakup of Pangaea. As tectonic plates shift, they not only alter geographical landscapes but also influence ocean currents and climate systems. These changes have long-term implications for modern ecosystems, as they affect species distribution, migration patterns, and interactions among organisms across different regions.
• Evaluate how the fossil record supports theories about Pangaea's breakup and its impact on biogeographical distributions.
  • The fossil record offers critical evidence for theories regarding Pangaea's breakup by showing similarities in species found across now-separated continents. For instance, fossils of plants and animals like Glossopteris and Mesosaurus indicate these organisms thrived when continents were connected. As these landmasses drifted apart, their respective populations evolved independently, leading to current biogeographical distributions that demonstrate both shared ancestry and unique adaptations shaped by isolation.

Related terms

Continental Drift: The theory that continents have moved over geological time and were once joined together in a supercontinent before drifting apart.

Plate Tectonics: The scientific theory explaining the movement of the Earth's lithosphere, which is divided into tectonic plates that float on the semi-fluid asthenosphere.

Biogeography: The study of the distribution of species and ecosystems in geographic space and through geological time, which was profoundly affected by events like the Pangaea breakup.