ONCE UPON A TIME
From the beginning
When the sperm whale, Parāoa was very young and lived on land it was best friends with Kauri, but the call of the sea became strong as their Godwanaland home broke apart and ancient New Zealand began to sink beneath the waves. Parāoa went to sea, leaving Kauri with a gift of his skin to protect him when the sea rose over him, but this never happened and Kauri lives on on dry land as Parāoa roams the oceans.
While this ancient story of the whale and the tree may sound fanciful to many, it is surely not as bizarre as that constructed by geologists and palaeohistorians from the meagre evidence of lonely fossils and patterns in rock.
They tell us that Kauri is truly ancient, emerging in the primeval forests of the greatest landmass that has ever existed on Earth, the huge southern continent known as Godwana. That happened some 250 million years ago, well before the forebears of whales began to crawl out of the forest and down to the sea. Those creatures, having gifted their skin to Kauri as the story tells, are known as creodonts, and by the time they decided to take to the sea Kauri was already 190 million years old, the tupuna of a great family of trees, called conifers, that have matched whale’s wanderlust by colonising almost every area of land on Earth. By the time the creodonts morphed into archaeocetes, the first creatures we could identify as ancestral whales, New Zealand had been usurped by the Great Southern Ocean and reverted to a collection of islands that was isolated from the rest of Godwana. New Zealand began to resemble the oceanic group of islands we now recognise, while the rest of Godwana was driven off by the fantastic forces of plate tectonics to become Australia, South America and India.
While the break up of Godwana is an immense event, it did not happen quickly, rather it moved with such profound slowness that many of the creatures disrupted by it would have been unable to measure its progress through the span of their generations. During this colossal disruption Kauri was isolated from his descendents, the whanau of conifers that the scientists call Araucariaceae. In the full flush of its youth, this family, headed by Agathis Australis, to give Kauri its formal name, shared the earth with dinosaurs for almost 200 million years, and in the isolation of New Zealand, Kauri’s original home, has kept company with one small remnant of that epic era ever since, Tuatara that scientists call Sphenodon.
Tuatara is often referred to as a surviving dinosaur although this is not strictly correct, even if its spiny back and lizard like appearance suggest otherwise, but it is not the only ancient one that Kauri once shared the forests with since the time of Godwana.
Amongst these is the remarkably large and diverse family of native earthworms which work the soil from leaf litter to deep clay, including the giant that reaches 1.5 metres in length and 12 cm thick, driving its tunnels 4 metres underground.
There is also the weta, the large cousins of crickets that have taken on the role of small mammals once occupied by Parāoa’s ancestors the creodonts, and have grown to become the largest of the fantastic insect family. There are also giant carnivorous snails, one of which is mistakenly known as the Kauri Snail, and rare native frogs that are the most primitive of all surviving frog species.
Another creature that Tuatara would recognise from Godwana days is the silky, worm-caterpillar found in Northland bush today that was ancient before Kauri was born. Peripatus looks relatively benign, but it has a wicked way with its prey, spitting slime onto its victims which hardens and keeps the unfortunate still throughout mealtime. But this horrific phenomenon is not the reason Peripatus fascinates biologists, rather it is its place in the order of living things. Neither an annelid (a segmented worm) nor an anthropod,( an animal with legs) Peripatus fills a unique niche that could be a link between the two orders, or simply an evolutionary dead end. Either way, it draws researchers to lifting rocks in Northland’s forests.
What tuatara, weta and Peripatus do show is what a time of innovation Godwana occupied in Earth’s history. Large and dry the continent offered numerous environments where evolving terrestrial creatures could find new opportunities for biological innovation, and many of them, Araucariaceae included, did just that.