Stuff To Blow Your Mind The Wallace Line, Part 2
Aug 21, 2025
Discover the fascinating life of Alfred Russel Wallace and his groundbreaking contributions to natural selection. Explore the intricate Wallace Line and its significance in biogeography, revealing how geological history has shaped today’s biodiversity. Unravel the migration patterns of vertebrates between Asia and Australia, learn about unique barriers faced by species, and dive into the ecological challenges facing sharks today. Join the journey through nature's boundaries and Wallace's enduring legacy in science.
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From Sharp Line To Transition Zone
- The Wallace Line began as a sharp boundary but later became seen as a permeable transition zone called Wallacea.
- Biogeographers updated the idea as more exceptions and mixed faunas were discovered across the region.
Deep Trenches Keep Faunas Apart
- Deep ocean trenches like the Lombok Strait prevented land bridges even during low sea levels, keeping faunas separate.
- Plate tectonics later explained these trenches and long-term isolation of Sunda and Sahul.
Lost Continents Filled Scientific Gaps
- Continental extensionism (lost continents) overused land-bridge ideas to explain distributions and led to mythic hypotheses like Lemuria.
- Wallace and others moved toward explanations combining land bridges and long-distance dispersal.
