[mamelukesabre]

presumably an adaptation to cope with carrying loads.
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More likely an adaptation to slower speeds. Hauling water or food for a human doesn’t require fleet footedness.

[Kenny Bunk]

More likely an adaptation to slower speeds. Hauling water or food for a human doesn’t require fleet footedness

These adaptations are much more likely due to selective breeding for compactness and load-carrying ability. Evolution doesn't work all that fast.