The takah?, a flightless bird native to New Zealand, has long been a subject of scientific debate regarding its history and origins. However, recent research has shed new light on the significant impact of humans and past climate change on the takah? population. Genetic analysis has also revealed that the takah? is closely related to its extinct North Island cousin, the moho, contrary to previous beliefs.
Previous genetic analysis suggested that the takah? and moho were not closely related and descended from separate arrivals to New Zealand by an ancient species of swamp hen. However, new research using palaeogenetic techniques has found that the Australian or Pacific swamp hen ancestor of the takah? and moho arrived in New Zealand four million years ago. Around 1.5 million years ago, a land bridge between the North and South Islands allowed the swamp hen to evolve into the takah? in the south and the moho in the north.
During the last ice age, takah? were restricted to isolated areas in the northwestern and southern South Island. As the climate warmed, their distribution shifted to eastern and southern regions. However, the arrival of East Polynesian colonists in the late 13th century had a significant impact on the takah? population. Over-hunting, habitat destruction, and predation from rats and dogs resulted in the loss of takah? everywhere except Fiordland. This led to a small and inbred population with little genetic variation.
The demise of the moho and near extinction of the takah? allowed the p?keko, a bird from Australia, to colonize New Zealand around 500 years ago. The research highlights the importance of using the fossil record to inform conservation management decisions for endangered species like the takah?. It is crucial to understand their true biological heritage and preferred habitats in order to effectively protect their populations. Conservation efforts should focus on maximizing genetic variation and minimizing inbreeding to ensure the long-term survival of the species.