The ancient tetrapod footprints in Poland were found on a former marine tidal flat or lagoon in an abandoned mountain quarry, suggesting the evolution from fins to limbs occurred in an intertidal or lagoon environment rather than a seasonally flooded forest.
Sources
- Oldest Land-Walker Tracks Found--Pushes Back Evolution (nationalgeographic.com)
- https://www.nature.com/articles/nature08623 (nature.com)
- https://www.earthmagazine.org/article/tetrapod-tracks-reset-timing-four-legged-evolution/ (earthmagazine.org)
- https://www.nbcnews.com/id/wbna34730426 (nbcnews.com)
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