Sunday, 29 April 2007

Maori sweet potato from afar

THE great kumara conundrum is set to be solved, throwing up a bit of long-distance controversy on the way.
As you’ve tucked into your Sunday roast, or battled your way through bumpy purple skin inadequately armed with a (sweet) potato peeler, you may have presumed the roots of this vegetable are firmly embedded in Polynesian soil.
Not so.
Fresh studies from Massey University show the kumara hails from South America.
PhD student Andrew Clarke says linguists learnt long ago the word “kumara” is not actually Maori, but a word given to the sweet potato by South American Indians.
“The major thing we are interested in is whether Polynesians sailed to South America about 1000 years ago during which they collected the kumara,” says Clarke, who is studying at Massey’s Allan Wilson Centre for Molecular Ecology and Evolution in Palmerston North, New Zealand.
“It was definitely in Polynesia about 1000 years ago,” he says.
Fossilised kumara found in the Cook Islands confirm this and now genetic fingerprinting shows that a family of sweet potato from Peru is closely related to those from Polynesia.
Maori brought kumara to New Zealand when they settled in these southern islands 700 years ago, and Captain Cook found it when he charted these waters in the 1760s.
While this may all sound ho-hum, the kumara connection points to a contentious scenario previously way beyond European imaginings, Clarke says.
If the kumara does indeed come from South America, then Polynesians must have undertaken massive ocean voyages through wild seas many years before Europeans could sail these areas. “It’s controversial because it’s such a long way to sail and then you are sailing into the wind,” he says.
Easter Island is the closest to the continent and that’s still 3000kms away, he says.

Kauri says 'no' to theory

WHILE people today face the rising tides of global warming, some Kiwi scientists are debating flooding theories from the past.
Way back – about 30 million years ago – in the Oligocene period New Zealand was allegedly completely under water.
This hypothesis, released in a paper last year, is being refuted by Associate Professor Peter Lockhart from Massey University and a mighty tree.
“The kauri says ‘no’. It’s an example of a plant group that’s got an unbroken heritage with Gondwana,” he says, referring to the land mass New Zealand was part of before it began breaking away from Australia about 80 million years ago.
Fossil records and molecular clock dating show kauri was here 100 million years ago and has survived through the ages.
Dr Lockhart does agree that a great deal of New Zealand was under water in the Oligocene period, but for the kauri to have continued its family tree, unbroken, proves without doubt, the completely submersed theory can’t be right.
And what about our wee living dinosaur: “Where was the tuatara during this time – was it hanging out in hamburger bars in Sydney?”

Brains even brainier

REMEMBER that old threat thrown at people with a liking for liquor: “You’ll kill your brain cells and they won’t grow back.”
Here’s a slight reassurance – only the killing part is right.
Research from Auckland University’s brain research team has shown that we do grow new brain cells.
Professor Richard Faull and his team discovered that amazing fact back in 2003.
This year, they have made another major breakthrough.
“We have found the pathway which the new brain cells follow in the human brain,” Prof Faull says.
This finding offers new hope for people suffering from Huntington’s, Parkinson’s and Alzheimer’s disease, plus stroke victims.
“It’s not a cure; it’s another means whereby we can help people with brain disease in the future,” he says.
“By knowing how stem cells move around, we can now look at new ways to regenerate cells and repair damage to the areas of the brain affected by these conditions.”
Prof Faull, originally from Tikorangi in Taranaki, has the more brains than anyone else – literally.
He is responsible for amassing the world’s largest human brain bank, which has provided the neurological material for his team to study.