Trying to make sense of New Zealand's flora and fauna has kept entomologist, George Gibbs occupied for six decades.
Dr Gibbs is a retired university lecturer, and his fascination with the natural world goes back as far as he can remember.
Prior to teaching at Victoria University he studied there and then gained a PhD in insect ecology from the University of Sydney.
The evolutionary history of moths, butterflies and weta has always been at the forefront of his research.
Research trips have seen him travel to a range of destinations, including Patagonia, South Africa, New Caledonia and Australia.
His award winning book Ghosts of Gondwana was first published 2006, and is a previous winner of the environment category at the Montana Book Awards.
A new fully-revised edition has just been published
Dr Gibbs specialises in bio-geography, or what lives where, and why.
“It’s dependent on geology and tectonic theory, continental drift blew it [the field of bio-geography] all apart, had it start again when that came in and it’s continually being adjusted for whatever the latest discoveries are - which is what makes it exciting.”
Dr Gibbs says the book is a big picture exercise, an attempt to put pure science into everyday language.
And he says New Zealand’s flora and fauna has a deep history.
New Zealand and Australia were all part of the same block of land until about 80 million years ago. Which is why so many remnants of Australian-like life can be found here.
The climate here was more once more Australian too.
“We had masses of eucalypt forests, gum trees, 20 million years ago. Otago was covered in gum trees, it had forest fires, had a climate the same as Australia’s today – dry and hot.”
But a severe ice age put an end to that.
“Being bigger and further north, Australia survived it better, we lost a lot of Australian looking organisms at that time.”
The idea that New Zealand was completely submerged 20 million years ago is now largely rejected as a feasible hypothesis, Dr Gibbs says. The debate to prove it true or otherwise, however, provided geology with a fillip.
“After all that effort, there was a conference of the geological society in Nelson and they looked at all the data and they all presented their papers and there wasn’t a single one in favour of it.
“I call it a myth, which is a bit cruel because it’s a hypothesis, scientifically valid, but we’ve dumped it.”
So some of what is now New Zealand remained above water and there was no big extinction.
“It didn’t drown completely, it was above water but it was very broken up apparently probably better thought of as an archipelago of islands - low lying islands - this was before our mountains ever arrived and it had a huge amount of wildlife on it.”
Dr Gibbs says fossilised remains of flora and fauna found in one paddock in Southland indicate more diversity than the whole of New Zealand today.
A discovery made since the publication of the first edition of Gondwana is a kiwi fossil – a surprise perhaps that none had been found before.
“We haven’t got any fossils of moas or kiwis, other than a few thousand year old bones which we find in caves and so on which is really today’s fauna - so we’ve got no history of how these birds went through their evolution.
“To find a fossil kiwi about 20 million years old was exciting in its own right, and it’s a much smaller bird than the one that lives today - a third of our smallest bird today.”
And this ancient kiwi may have been able to fly once, which he says raises the possibility kiwis might have flown to get here rather than hitching a ride on a drifting land mass or walking.