The Swansea-based scientist spent years piecing together ancient DNA 2 puzzle that suggests hunting by humans caused this giant seabird's demise.
Dr Thomas studied bone and tissue samples from 41 museum specimens
during a PhD at both Bangor and Copenhagen University.
The findings paint a picture how vulnerable even the most common
species are to human exploitation.
Storybook seabird
About 80cm (2ft 7in) tall, the stubby-winged and bulbous-billed great auks
used to be found all across the north Atlantic - from North America through
Greenland, Iceland, Scandinavia and the UK.
"Being flightless, they were always targeted local people for food and for 12 their feathers," says Dr Thomas.
"But around 1500, when European seamen discovered the rich fishing
grounds off Newfoundland, hunting intensified."
By about 1850, the great auk was extinct; the last two known specimens were 16 hunted down by fishermen on Eldey Island, off the coast of Iceland.
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One of these signatures might be a lack of genetic diversity, suggesting
individuals were inbreeding and the species, as a whole, was becoming
vulnerable to disease or environmental change.
"But their genetic diversity was very high - all but two sequences we found
were very different," Dr Thomas said.
In fact, the genetic timeline Dr Thomas and her colleagues were able to create 26 - published in the journal eLife - showed that, at the time the intensive great 27 auk hunting began, the species was doing "really well".
"They weren't at risk of extinction at all," said Dr Thomas.
"It emphasizes how vulnerable even the widespread and abundant species
are to this intensive, localized pressure."
Source (adapted): https://www.bbc.com/news/science-environment-50563953.
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