The presence of fossils from the same species on continents that are now separated by oceans could be explained through several mechanisms, even without the existence of a supercontinent. Here are some possibilities:
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Land Bridges: In the past, there have been periodic changes in sea levels due to glaciation or other geological processes. During these times, land bridges could have formed between continents, allowing species to migrate between them. For example, the Bering land bridge once connected Asia and North America, facilitating the movement of species.
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Island Hopping: Some species may have been able to migrate from one continent to another via a series of islands. If a species was able to travel over water or was capable of surviving on islands, it could eventually reach distant land masses.
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Continental Drift: Even without a fully formed supercontinent, the theory of plate tectonics suggests that continents have been drifting apart over millions of years. Fossils of the same species could be found on different continents if they were once connected and the species lived there before the continents split and drifted apart.
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Similar Environmental Conditions: If two continents had similar environmental conditions (e.g., climate, ecosystems), a species could evolve in both locations separately. This would lead to similar adaptations in different locations without direct migration or a common ancestral population being present at the same time.
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Floating Debris: Some small organisms and their larvae can survive long durations on floating debris or vegetation. This mode of transport could allow organisms to drift from one landmass to another over time, leading to the establishment of populations in distant locations.
Each of these mechanisms could provide a plausible explanation for the presence of the same fossil species on now-separated continents, illustrating the complex histories of life on Earth.
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