Page 78 - BBC Wildlife - August 2017 UK

The conservationists have been doing basic genetic
tests on kakapo for years. To avoid inbreeding, it’s
important to know how the birds are related to one
another. Kakapo are polygamous, meaning both sexes
mate multiple times with multiple partners. A female
may then lay a mixed clutch containing eggs from
different fathers, and when they hatch the males make
no contribution to raising the young. It makes working “SEQUENCINGTHE GENOMES OFALLLIVING
out ‘who’s the daddy’ a total nightmare.
In 2003, Bruce Robertson of New Zealand’s Otago KAKAPO COULD GIVE US MUCH MORE
University developed a ‘relatedness’ test based on small
snippets of kakapo DNA. It indicates whether or not INSIGHT INTO THE PROBLEMS WE HAVE.”
Kakapo with egg & feeding: Andrew Digby; researchers: Tui De Roy; camera trap & weighing: Stephen Belcher
two kakapo are related, though can’t tell the difference
between siblings, cousins or parent-offspring pairs. The
test has been a breakthrough. The birds’ transmitters Above: females that, they’d be able to tell how inbred, or not, the birds
relay information, not just about location, but about nest inside hollow are, if there’s a genetic basis to their fertility problems or
logs, rotten
activity. This can be sent directly to the recovery team’s the sorts of disease they develop, and whether birds from
stumps or under
computers, so when they arrive at work in the morning they knotty tree roots. different places have different DNA.
can tell exactly which birds have mated during the night. They lay two Preliminary tests suggest that birds descended from
If a tryst is deemed unsuitable – if the birds are related, to three eggs the Fiordland and Stewart Island populations are indeed
and rear their
too young, or already overrepresented in the gene pool – genetically different. For example, one of the original
offspring alone.
then the team spring into action. They catch the female Fiordland birds, known as Richard Henry, had different
kakapo then inseminate her with freshly collected sperm wing markings, sang in a different dialect (he boomed
from a preferred suitor. The hope is that the new sperm but did not ching) and carried unique versions of two key
will outswim its rivals. In addition, it’s been shown genes related to immune system functioning. But of his
that multiple matings increase a female kakapo’s fertility, three offspring, so far only one – Gulliver – has been shown
so the strategy gives would-be mothers the best chance to have inherited this unusual DNA and he has yet to
of starting a family. become a father. When the researchers decode the genomes
of Gulliver’s siblings Sinbad and Kuia, and of Kuia’s chicks,
FAMILY HISTORY they expect to find other unique DNA sequences.
Digby realised if they had the full genetic sequence for If the team could analyse the full genomes of all the
every single bird, then the foggy kakapo family tree would kakapo, they would undoubtedly uncover more of these
become resolved with crystal clarity. They’d be able to tell idiosyncratic DNA patterns. Then they’d be able to tailor
exactly how every bird is related to every other. Not just their breeding programme based on a detailed knowledge
78 BBC Wildlife August 2017