In contrast with previous work, which emphasised changes to protein-coding DNA as driving flightlessness, the new study associated loss of flight more strongly with regulatory evolution in "non-coding" DNA. The study, led by Harvard University researchers, drew on genetic analyses of kiwi blood samples that were permitted by Ngai Tahu and Te Ati Awa iwi, along with moa and kiwi specimens collected by the late Professor Allan Baker.
Another Otago University researcher who wasn't part of the study, Dr Nic Rawlence, said the evolution and loss of flight in ratites had long fascinated scientists. Are there glaciers in the North Island? Are there moose in Fiordland? Why Can't Kiwis Fly?
Crammed full of fascinating, fun and sometimes challenging facts, it's a lively, bite-sized introduction to our natural world. Gerard Hutching. He is married with three children and lives in Wellington. Search books and authors.
Gerard Hutching Buy from…. Darwin noticed, and he predicted that ratites were related to each other. His contemporary, Thomas Huxley , found another commonality among them: The arrangement of bones in the roofs of their mouths appeared more reptile-like than that of other birds. At about the same time, another biologist, Richard Owen , assembled the remains of a giant ostrich-like fossil skeleton, the first extinct moa known to the western world.
But a pesky detail puzzled Huxley: Small, ground-dwelling South American tinamous didn't seem to fit neatly with the ratites or other birds. Tinamous fly, albeit reluctantly. And they possess keeled sternums, suggesting that they evolved with flying birds. But their palate bones match the ratites. Where do they belong? Scientists have debated this question for years. Now, a new study in the journal Molecular Biology and Evolution , analyzing the largest molecular dataset to date, clarifies the tinamous' place on the evolutionary tree and offers clues about the origins of flightlessness.
To sort out the details, scientists probed almost 1, DNA segments from tinamous, emus, ostriches, the extinct little bush moas, and others. After sandblasting and pulverizing an ancient moa toe bone to chemically extract and sequence the DNA, scientists compared its DNA with that of the other species and ran multiple computer models simulating molecular evolutionary changes.
Some earlier studies, which have generally showed tinamous on the outskirts of the ratite group, relied solely on morphological traits like skeletal details. Other investigations of limited genetic information suggested tinamous were evolutionarily tangled with the flightless birds. The results were staggering, Baker says.
The tinamous evolved within ratites, not as a separate lineage. Moa breastbones, toe bones, leg bones, and even the occasional skull rested in the mud, the final resting place for birds chased and slaughtered by humans about 12, years ago. The kiwi is much more than just a native New Zealand bird, it's an iconic symbol of the nation. Although the kiwi is a bird, kiwi are not able to fly. This isn't unusual in New Zealand, which is home to more species of flightless birds than anywhere else in the world.
The unique location and history of the country has meant historically birds didn't need to fly to avoid land-based predators, they could happily forage and nest on the ground. The fact the kiwi could only really have evolved in New Zealand, combined with their quirky characteristics , makes them the perfect symbol to represent the unique characters you'll meet on a trip to New Zealand.
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