The current evolutionary narrative suggests the kiwi lineage diverged from other ratites very early on. Approximately how long ago might this separation have occurred?
Answer
Around 85 million years ago
The timing of the initial divergence for the kiwi lineage is estimated to be profoundly ancient, potentially around 85 million years ago. This timeframe aligns with the initial separation of New Zealand from the larger Gondwana landmass. Such an ancient divergence places the kiwi’s initial evolutionary split alongside the late Cretaceous period, long before the major diversification events seen in many other modern bird groups. This immense temporal depth is what explains why the kiwi's closest relative, the elephant bird, ended up on Madagascar, emphasizing a dispersal event linked to ancient continental positions.
Related Questions
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