Thousands of species have humans to thank for
bringing them to islands throughout the Pacific.
But there's one animal that has been a valued travelling companion
for as long as people have sailed this ocean.
Wherever people went,
pigs went too.
In Vanuatu,
1,200 miles north of New Zealand,
the people of Tanna Island have gathered for a festival.
Like an expensive car in Western culture,
here pigs are a symbol of wealth and status.
The Toka festival celebrates the end of warfare between rival clans,
and pigs are at the centre of it.
To attend, each village must bring some to the party,
that's a lot of pigs.
Some will be butchered for a feast,
others given away.
But to take one of these pigs home,
a family must agree to one day repay the debt
and it's these pig debts that help strengthen the bonds
between the different villages.