Continental drift

Definition

Continental drift is the theory that continents have moved over geological time and were once part of a single supercontinent called Pangaea. This movement has influenced the distribution of species, climate changes, and the evolution of ecosystems across the globe.

5 Must Know Facts For Your Next Test

1. The concept of continental drift was first proposed by Alfred Wegener in 1912, who suggested that continents were once connected and have since drifted apart.
2. Evidence supporting continental drift includes the fit of continental coastlines, fossil similarities across oceans, and geological formations that match on different continents.
3. Continental drift plays a key role in explaining the distribution of flora and fauna, showing how geographic barriers influence species evolution and adaptation.
4. The movement of continents can lead to significant geological events such as earthquakes and volcanic activity, impacting local ecosystems and species distributions.
5. Modern advancements in technology, like GPS and satellite imaging, have provided more precise measurements of continental movement, affirming the principles of continental drift.

Review Questions

• How does the theory of continental drift relate to the distribution of species across different continents?
  • The theory of continental drift explains how continents have shifted positions over millions of years, which has influenced the distribution of species. When continents were joined as Pangaea, species could move freely across land. As they drifted apart, geographic barriers formed, leading to isolation and divergence in species evolution. This process helps explain why similar species are found on distant continents and how they adapted to different environments.
• Evaluate the evidence that supports the theory of continental drift and its impact on modern biogeography.
  • Evidence for continental drift includes fossil records showing similar organisms on separate continents, the matching geological formations on different landmasses, and patterns in species distribution that correlate with historical continental positions. This evidence highlights how continental drift has shaped modern biogeography by influencing how species evolve in isolation or adapt to new environments after being separated by oceans. It underscores the importance of geological history in understanding current biodiversity.
• Analyze the implications of continental drift for understanding climate change and ecosystem shifts over geological time.
  • Continental drift has significant implications for climate change and ecosystem shifts. As continents move, they can alter ocean currents and atmospheric circulation patterns, which can lead to drastic climate changes over time. These shifts affect ecosystems by changing habitats and influencing species interactions. The study of past continental movements provides insight into how current climate changes might impact biodiversity and ecosystem stability in the future.

Related terms

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

Pangaea:

A supercontinent that existed during the late Paleozoic and early Mesozoic eras, believed to have started breaking apart around 175 million years ago.

Biogeography:

The study of the distribution of species and ecosystems in geographic space and through geological time, influenced by factors like continental drift.