 Protea neriifolia variant, Family Proteaceae Photo by the Author New Zealand: A Late-Paleozoic Part of South America
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| New
Zealand: a
Late-Paleozoic Part of South America By Harry Levin copyrighted Abstract In what may be termed “one of the grand puzzles of the earth’s prehistory,” New Zealand and Chile, as a common native habitat, share the earth’s oldest, most primitive flowering plants, side by side with the earth’s most ancient conifers. New Zealand and Chile are now some 9000 km. apart. In The Origin of Species, in 1859, Charles Darwin wrote: “New Zealand in its endemic plants is much more closely related to Australia, the nearest mainland, that to any other region: and this is what might have been expected; but it is also plainly related to South America, which, although the next nearest continent, is so enormously remote, that the fact becomes an anomaly.” This grand anomaly is resolved by evidence presented herein, which indicates that New Zealand was once part of South America on a fully consolidated Gondwanaland during the late Paleozoic more than 300 million years ago. A New Zealand block was then adjoined to the southwestern coast of Chile. This essay addresses the geological and biological relationships of New Zealand to South America and to Australia from the late Paleozoic to the present. 1
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| Molecular Genetic Support of Devonian Angiosperm Origin The basic hypothesis of Devonian origin of angiosperms (before 360 mya) is supported by studies of DNA These studies evince an early divergence of angiosperms from a Devonian plant (seed fern). Brief statements epitomizing five such studies: • V. Troitsky et al. (1) indicate (in 1991) by rRNA sequence comparisons that both gymnosperms and angiosperms are monophyletic groups. The genealogical splitting of gymnosperm and angiosperm lineages occurred at least 360 million years ago. Magnoliales were the earliest angiosperms. They are dicotyledons. • W. F. Martin et al. (2) indicate (in 1993), by chloroplast and nuclear sequence data taken together, that angiosperms and gymnosperms were separate lineages about 330 million years ago and that the separation of monocotyledonous and dicotyledonous lineages of angiosperms took place about 300 million years ago. • T. Kh. Samigulin et al. (3) indicated (in 1999), with partial sequences of the ropC1 gene, that both angiosperms and gymnosperms are monophyletic and that none of the recent gymnosperms is sister to the angiosperm. • S-M Chaw et al. (4) indicate (in 2000), with mitochondrial subunit rRNA sequences, that gymnosperms are monophyletic; that, in conjecture, the angiosperms too are monophyletic and substantially older than the fossil record indicates. • L.M. Bowe et al. (5) indicated (in 2000), with sequence data of evolving mitochondrial genes, cox1 and atpA, that extant gymnosperm genes are monophyletic and that angiosperm origin should be sought among extinct seed plant groups. 2
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| Introduction In The Origin of Species, 1859 (6), Charles Darwin wrote: New Zealand in its endemic plants is much more closely related to Australia, the nearest mainland, that to any other region: and this is what might have been expected; but it is also plainly related to South America, which, although the next nearest continent, is so enormously remote, that the fact becomes an anomaly. But this difficulty almost disappears on the view that both New Zealand, South America and other southern lands were long ago partially stocked from a nearly intermediate though distant point, namely from the antarctic islands, when they were clothed with vegetation, before the commencement of the Glacial period. The affinity, which, though feeble, I am assured by Dr. [Joseph Dalton] Hooker is real, between the flora of the south-western corner of Australia and of the Cape of Good Hope, is a far more remarkable case, and is at present inexplicable: but this affinity is confined to the plants, and will, I do not doubt, be some day explained. On the basis of his 1839-1843 voyages and observations with the H. M. Discovery ships Erebus and Terror, J. D. Hooker, in 1859 (7), averred that the evidence of similar flora on widely separate lands could not be explained without supposing that these lands once formed a continuous expanse. Indeed, for Darwin’s “affinity,” Hooker, perforce, included all biota. The Grand Puzzle In what may be termed “one of the grand puzzles of the earth’s prehistory,” New Zealand and Chile, in common, share native habitat of earth’s oldest, most primitive flowering plants, side by side with the earth’s most ancient conifers. New Zealand and Chile are now some 9000 km. apart. This grand puzzle is resolved herein: New Zealand was once part of South America on a fully consolidated Gondwanaland during the late Paleozoic more than 300 million years ago. A New Zealand block was then adjoined to the southwestern coast of Chile. From that late Paleozoic date to the present, this essay addresses the geological and biological relationships of New Zealand to South America and to Australia. Premises for the Grand Puzzle Three premises are explicit to this essay: • During the late Paleozoic the southwestern region of South America, as part of Gondwanaland, was vegetated by a cool temperate rainforest containing both angiosperms and gymnosperms, both ancestral to the living forests of present-day Southern Chile. 3
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• Subsequently, during the late Paleozoic, a landmass of obscure contour, here termed the “New Zealand Plate,” and bearing New Zealand, broke away from South America and drifted toward the southeastern margin of Australia, while carrying a cover of indigenous rainforest angiosperms, conifers and other biota. This landmass came to rest joining margins with Southeastern Australia about 260 million years ago. • No natural transfer of cool-rainforest trees between Australia and New Zealand resulted from the re-location of New Zealand opposite Australia. The above premises are buttressed by absence of fossil evidence of mammals – including Australian indigenous marsupials – ever endemically inhabiting New Zealand, except for bats. This thesis posits that except for flying creatures and the effects of mankind, there has been “total non-connect” of flora and fauna between Australia and New Zealand; that New Zealand never was a part of Australia except by submarine attachment; and that New Zealand is an above-water (outcropping) region of a volcanic-distorted block, herein termed “New Zealand Plate,” that rifted off the western coast of South America during the Permo- Carbonaceous Ice Age, i.e., probably about 280 Ma, and found its way to the margin of southeastern Australia. 4
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| Part1:
Geological Aspects in Evidence Cambrian Existence of New Zealand There is evidence that New Zealand existed somewhere as early as the Cambrian era more than 500 million years ago. This evidence is thus, that the northwest corner of the South Island of New Zealand strongly indicates that it was once part of a perigondwanic craton arc system extending landward out to the western coast of South America. This corner of the South Island is the Kagurangi National Park, which contains Cambrian and Ordovician material in distributed belts among Mesozoic bathylithic intrusions. Interestingly, the belts contain Ordovician fossils such as trilobites and graptolites, among sedimentary rocks. This evidence is convincing that New Zealand, as part of a “New Zealand Plate,” is, in fact, of pre-Devonian age. The New Zealand Plate Evidence will be cited in support of Devonian Gondwanaland origin of angiosperms and in support of both angiosperms and conifers being present over a consolidated Gondwanaland expanse stretching from Australia to South America prior to 300 Ma. Hence, it is highly probable that during the late Paleozoic, the New Zealand Plate, along with contiguous portions of South America, was largely covered by angiosperm and conifer flora bedded on Cambrian and Ordovician substrate. In hypothesis, the New Zealand Plate, a continental block of obscure conformation, broke away from South America, and drifted off toward Australia, to be re-configured by geological activity to its present form as shown in Figure 1. Bathymetric Map of New Zealand Plate and Surroundings Figure 1 presents, a bathymetric map of a region of the Southwest Pacific, in which the present-day New Zealand Plate and New Zealand are in relationship to their immediate surroundings. Also shown are New Caledonia, Fiji, Vanuatu, Norfolk Island, and the Solomon Islands, in context with the Norfolk Ridge, the Lord Howe Rise, the Gilbert Seamount, and the North and South Fiji Basins. All are germane to this presentation. (The basic map is here referenced as K. Hoernie et al (8). It was obtained in Project Zealandia by scientists of the Geomar Research Center of Kiel and others, in 2002-2003.) The New Zealand Plate may have had elongated form when it rifted from what is now the southwest coast of Chile. While still attached, it probably reached from 29 S. toward the Fuegan end of Chile. It likely was the terminus of a South American Cambrian/Ordovician magmatic belt known as the Rio de la Plata Craton. Before the rise of the Andes, that craton extended through the Argentine provinces of San Juan and Mendoza to the coast –and there into the New Zealand Plate. It is likely that Cambrian and Ordovician crustal material once covered much surface of New Zealand. (On a global view, the New Zealand Plate had likely been the extreme western end of a perigondwanic magmatic Cambrian/Ordovician arc that included the following cratons: Kaapaal in South Africa; Kaapvaal-Grunehogna in East Antarctia; Yilgarn in West Australia; and perhaps even the Lachlan Mountains of New South Wales. There are also indications that Africa and South America, during the Cambrian/Ordovician, were united just west of the Kalahari Craton, an older craton in southern Africa.) 5
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Baja South America In severance from South America, (perceived in Figure 2), the New Zealand plate took along members of families of ancient, primitive rainforest trees – leaving behind other members of the same families. Remarkably, high densities of these relic ancient, primitive families are alive today at the southern extremity of South America. This region, which is situated between 37 and 55 S latitude, is here referred to as “Baja South America,” or simply as “Baja”. During the late Paleozoic, this region lay south beyond the devastating ice sheets of the Permo- Carboniferous Ice Age of 300 to 250 million years ago. Hence, its rainforests were able to survive. Today these ancient trees come first into notice on the southern slopes of the Andes from about 37 S southward. They spread cover over two temperate Chilean rainforests, the Valdivian, from 41 to 43 S, and the Magellian, from 43 to 55 S. In these rainforests, 95% of the trees are endemic, and Nothofagus and Podocarpus are prominent. Baja South America can be viewed as “a land of living fossil trees,” isolated from other forested areas. 6
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Voyage of the New Zealand Plate In hypothesis, after breaking away from South America, the New Zealand Plate drifted past Antarctica and entered into the Australia domain. The geography of the Gondwanaland continents during the late Paleozoic suggest a short route, for example, the possible route, shown in Figure 2 (with B. Windley (9) chart, 1995 as a base) Today, in order to go from South America past Antarctica to Australia, a nomad New Zealand would have to travel about 9000 kilometers west from South America. See Figure 3. During its voyage, and especially thereafter, the New Zealand Plate has met with conditions of intense geological foment, attended at times by rapid sea level and climate changes. Regions have been submerged, obliquely subducted, compressed, uplifted, transform-faulted, lava-suffused, contorted, or rifted in geological confrontation with ocean plate tectonics; and these actions have apparently heightened since the late Cretaceous, continuing even at present. |
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The Above-water Region, New Zealand These same geological dynamics applied to above-water New Zealand, as well. There remains very little of identifiable upper surface that it brought with it to the vicinity of Australia, (probably in the late Permian). The New Zealand Plate may have begun its close encounter with Australia about 260 million years ago. 7
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| Indications of late-Permian
arrival are offered by volcanic Red Rock near Wellington; by an
ophiolite belt on Dun Mountain near Nelson; and by other rocks here and
there on North and South
Islands. New Zealand consists of two large islands and a number of smaller islands that have not drifted away. In area, it is estimated to represent about 12 % of the entire New Zealand Plate. Its total area is 250,000 sq km, thus indicating a present area of about 2,000,000 sq km for the New Zealand Plate. Today, the country of New Zealand is about 2100 km from Australia. The Gilbert Seamount Approach, New Zealand to Australia Geological evidence fails to indicate that an overland passage ever existed between Australia and New Zealand. By evidence presented below, New Zealand was, at its closest approach, separated from on-shore Australia by at least 450 km of salt water. The Gilbert Seamount (in Figure I) is evidence of an undersea terminus of the continental New Zealand Plate – of a prolongation of the plate that has imposed a minimum separation of 450 kilometers between the present New Zealand and Australia, the separation later increasing accordingly by the interposition of the Tasman Sea (about 80 million years ago). It implies a formidable rebuttal to any conception of an overland passage of flora and fauna ever between Australia and New Zealand. The Gilbert Seamount is an elevated continental fragment separated from the adjacent Challenger Plateau. It has an area of about 11,500 sq km. It is elongated northwest to southeast. It is located at 450 km west of South Island, New Zealand, and it has been considered continental in origin. The source of the following regarding the Gilbert Seamount is a paper by R. A. Wood, 2001, (10). According to Wood, the Gilbert Seamount appears to be a prolongation of New Zealand, a western margin, a margin extending westward 450 km onshore from New Zealand. Both its continuous geological and morphological connection to the New Zealand mainland support this assertion, since there is a continuous connection of continental rocks between the seamount and mainland New Zealand. Hence, here is indication that, before the intervention of the Tasman Sea about 80 million years ago, New Zealand was in some manner of connection with the continental margin of Australia at the Gilbert Seamount. Hence, the New Zealand inland was never closer than 450 kilometers to Australia’s own southeastern margin. 8
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| To reiterate for its
significance: The above indications clearly argue against
overland passage or land bridge for flora and fauna from Australia to
New Zealand. Contrary to a land connection, they evidence a
450-km underwater shelf, an integral part of the New Zealand
Plate, reaching perhaps all the way to the marginal edge of
Australia from onshore New Zealand and thereby arguing that that
marginal edge of Australia was never closer than 450 km to New
Zealand from the time of the latter’s arrival about 260 million
years ago to the opening of the Tasman Sea. Geological and Climatological Circumstances Concurrent geological and climatological events in context raise serious objections to the existence of an overland biotic passage between Australia and New Zealand. One such objection is that sea level rose worldwide at the beginning of the Cretaceous, from about 130 to 100 Ma. It caused an inland sea in North America from Alaska to the Gulf of Mexico; and athwart Central Australia, it produced an epicontinental saltwater incursion that nearly reduced Australia to the shape of two long islands. The vegetation of Central Australia may have been totally erased, and the flora of East and West Australia isolated. Central Australia emerged as a flat desert. On account of its salinity and aridity, it proved a lasting formidable barrier against the migrating and intermixing of flora. A second such objection is that the Tasman Sea opened about 80 Ma, in the late Cretaceous, and shifted New Zealand and, to a lesser extent, New Caledonia away from Australia. A third such objection is that Eastern Australia and Tasmania were within the Antarctic Circle during almost all of the Cretaceous (until after the breakaway from Antarctica.) This broad region was then dark for a part of the year, and had a cold temperate climate. The climate was, therefore, not conducive to rapid plant diversification and radiation. After Australia broke away from Antarctica, the situation of New Zealand was even more obscure during the Tertiary, due to plate movement, volcanic activity, and sea level changes. A period of low sea levels between 53 Ma and 23 Ma may have permitted overland passage between Norfolk Island and New Caledonia. But New Zealand 29 million years ago seems to have been flooded, at least partially. “The information [of the Tertiary] has been so churned up that it will be difficult to resolve.” Thus, D. H. Tarling, pioneer in the application of paleomagnetism to continental drift, sums it up in a personal communication regarding the Southwest Pacific (11). 9
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| Question
of Bathylithic Ascension with Overland Passage Citing its current position relative to Australia and New Zealand, it might be suggested that New Caledonia could have been on a raised conduit or land bridge out from Australia more than 80 million years ago. There are indications that New Caledonia came into existence about 100 million years just east of the Lord Howe Rise, the latter then in marginal attachment with Australia. However, the presence of New Caledonia gives no answer to the question whether an overland route, perhaps a sedimentary land bridge, developed, subsequently permitting access of angiosperms from Australia into New Caledonia, and from there, perhaps, into New Zealand. There is no evidence of such a passage – although there is a possibility that such a passage once existed and could have been subsequently destroyed. Vicariance describes phenomena of this nature. The hurdle remains: how to travel overland from New Caledonia to New Zealand? While New Caledonia is about 600 km closer to Australia than is New Zealand, today New Caledonia and New Zealand are about 1500 km apart over the Norfolk Ridge. Again, there may have been overland passage as far as Norfolk Island. But then, an overland route Norfolk Island to New Zealand is vastly more difficult to reconcile. These distances virtually shut the door to previous overland intercourse of angiosperms. Ancient Trees on New Caledonia, Fiji, and Vanuatu New Caledonia, Fiji, and Vanuatu share the store of ancient trees with New Zealand and South America – although, in seeming contradiction of age. New Caledonia is only about 100 million years old; Fiji is less than 80 million; and Vanuatu is less than 10. Here then, in explication: Beginning in the late Permian, upon becoming marginally attached to Australia, the New Zealand Plate entered into a hotbed of geological activity, mainly volcanism and earthquakes. By the Tertiary, the North Island of New Zealand had surrendered most of its Cambrian/Ordovician top cover to volcanism. But some of that extremely ancient cover had fragmented into numerous large and small island shards. The opening of the Tasman Sea (about 80 Ma) gave impetus to these islands drifting away, particularly northward, and finding allochthonous attachment to plateaus, rises, and seamounts – while carrying immigrant, prime-condition, ancient and primitive trees of South American ancestry. Some fragments found their way north to the narrowed top of the South Fiji Basin and became parts of Fiji (Figure 1). Other drifting islands became part of New Caledonia and its offshore islands, entering perhaps by way of the New Hebrides Trench. Less than 10 million years ago, other island shards of New Zealand origin participated in forming Vanuatu by becoming attached to seamounts, by way of the North Fiji Basin or the New Hebrides Trench. 10
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| Part 2: Biological Aspects in Evidence Introduction Fossils are by no means the only witnesses to earth history. The most ancient, most primitive trees and their insect pollinators – living today– at times are better witnesses where details of context and continuity of earth history are sought. These witnesses are especially valuable where fossils are absent. Geography of living plants and animals interacts herein with tectonics, sea level change, and climate in accounting for New Zealand’s past and present relation to Chile. The most ancient, most primitive trees on earth tell the story of the separation of the New Zealand Plate from South America. They are represented here by five families – the angiosperm families, Nothofagaceae, Proteaceae, and Winteraceae, and the gymnosperm families Araucariaceae and Podocarpaceae. These families are badges of the unity of South America and the New Zealand Plate that prevailed more than 300 million years ago. They continue to exist today on continents and islands now separated by thousands of kilometers. They are described in Table 1 below. Table 1: Description of Five S. Hemisphere Exemplar Plant Families |
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In the late Carboniferous 300 million years ago, Madagascar was attached to India and was near to Africa. Moreover, India, Africa, and Antarctica were either attached or in close proximity to each other through Australia. To emphasize, the three angiosperm and two gymnosperm families cited above more than 300 million years ago are averred here to have occupied the whole of the southern hemisphere supercontinent Gondwanaland, which was continuous from South America through Australia. The above five flora were present during the Carboniferous prior to the ice invasion, and before 300 million years ago. They occupied a continuous Gondwanaland expanse stretching from Australia to South America. Africa had been a main (middle) section that route of propagation. 11
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| The
Ice Age, the Linchpin of Antiquity The Permo-Carboniferous Ice Age (also known as the Gondwanaland Ice Age) began 300 million years ago and lasted 50 million years. Its magnitude dwarfed recent glaciations like those of the Pleistocene. According to D.H. Tarling and M.P. Tarling, 1971, (14), ice fields covered the eastern part of South America above 40 S latitude and well north into Brazil. It vastly obliterated the terrestrial life of Africa. In Africa, each of the above five families was severely affected to this day by the ice: 1) For the Proteaceae in Africa, the phylogenetic composition was altered from 14 tribes to essentially one tribe, the Proteeae. 2) For the Winteraceae in Africa, all traces were removed. 3) For the Nothofagaceae in Africa, all traces were removed. 4) For the Araucariaceae in Africa, all traces were removed. 5) From Africa, the Podocarpaceae were wiped out; but they managed to make a limited comeback along the southeastern coast of Africa probably via Madagascar as the climate later warmed. Hence, the Permo-Carboniferous Ice Age, begun 300 million years ago, is a linchpin date for a thesis of Devonian angiosperm and gymnosperm origin. Both biological and geological evidence have thus been offered in this essay that the New Zealand Plate is pre-Devonian. Further biological evidence will be set forth here that the above five tree families – from the distant past to the present – have simultaneously occupied New Zealand and Baja South America. The Five Examplar Tree Families The five cited tree families, each deduced to be more than 300 million years old, are today native to Baja South America and also to New Zealand, New Caledonia, and Fiji, 9000 kilometers away. Table 2 summarizes the salient facts:
12
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| As a most remarkable
example in Table 2, the same genus,
Gevuina, the
Chile hazel nut tree, of family Proteaceae, is endemic today on
New Caledonia, on Fiji, and also on Vanuatu, – and, amazingly,
on Baja South America, which is about 9000 km and some 300
million years away. Proteaceae cannot tolerate salt water. The Winteraceae are probably the oldest of the angiosperms. Like the Proteaceae, they probably originated in Eastern Australia. The Proteaceae, manifest a “living fossil” genus, Dilobeia, on Madagascar. As a parallel, the Winteraceae manifest a “living fossil” on Madagascar. It is the species Takhtajania perrierii. Both of these ancient living angiosperms mark essentially the same overland route west from Australia through Indian Madagascar through Africa and into South America more than 300 million years ago, before the Permo-Carboniferous Ice Age (300-250 Ma). In Baja South America today, there are the Winteraceae native plants, Drimys winteri and Drimys aromatica, 9000 kilometers and 300 million years from New Zealand. |
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Table 2 is consistent with an estimate here that the New Zealand Plate – bearing the above ancient tree families – broke away from Baja South America just before or during the Permo-Carboniferous Ice Age. (The southwestern coast of Chile is noted to have had no ice age glaciation (14).) It is considered here that the rift may have occurred at the beginning of the Permian about 280 Ma. The basis is an early warming and a momentous rise in sea level at coastal regions of Gondwanaland 280 million years ago. In evidence, M.T. Gibbs et al (2002) (15) wrote: “The Permian Period . . . contains the most recent transformation from a major glaciation to a generally ice-free state . . . Apparently, the deglaciation was relatively rapid, being mainly confined to the Early Permian Sakmarian [285-280 Ma] Stage . . . [A Glossopteris forest cover replaced ice sheets] and the early and ubiquitous Gandawanan sequence, from tillites to coal swamp deposits, indicates a major climate warming . . . ” The probability is high that at that time (280 Ma) tree-bearing landmasses other than the New Zealand Plate rifted off elsewhere – for example, from Antarctica or Australia – ferrying ancient trees to far-away continental and island sites. 13
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| Part
3: Further Biological and Geological Aspects in Evidence Introduction The task ahead is, namely, to provide evidence, example upon example, in support of Premise 2 that the New Zealand Plate was once attached to Baja South America (here 37 to 55 south latitude) and in support of Premise 3 that an overland passage has never existed for flora and fauna between Australia and New Zealand since the New Zealand Plate rafted to the vicinity of Australia. Territorial Family Ties That Outweigh Time and Distance The gymnosperm, Lepidothamnus, (family Podocarpaceae in Table 2) attests in strong support of Premise 2 that three of its species are very closely related although one is endemic to Baja South America, and the other two to New Zealand. The following is cited in 1981 by C. J. Quinn and P. Gadek (16): “Despite the marked geographical discontinuity, the [three closely related] species are united by their distinctive cone morphology with its erect ovule, the absence of resin ducts in the leaves which occur universally elsewhere in the family and a large number of cupressoid cross-field pits not found elsewhere in the family. Chemically, these species are also unique in the family, having cupressuflavone as their major biflavenoid constituent.” |
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| Though not mentioned in
Table 2,
impressive angiosperm family ties
belong to the order Laurales and contribute to the ancient rainforest
trees found in both Chile and New Zealand. Of family Monimiaceae, they
are represented by both Laurelia sempervirens and Laureliopsis
philippina, in South America. These species are in indigenous abundance
among the temperate rainforest trees on the Andean slopes and offshore
islands of the upper reaches of Baja South America. They are closely
related to the species Laurelia novae-zelandia present today in New
Zealand. A remarkable example of affinity of Fiji fauna to South America are two iguanas. One is the Fiji crested iguana, Brachylophus vitiensis, indigenous only to Yaduataba Island, near Vanua Levu in Fiji, and to a few smaller islands. Nearby, the other is the Fiji banded iguana, Brachylophus fasciatus. Their relatives are opined to live 10,000 km away in South America and on the Galapagos Islands (once within reach of South America by archipelagos now under water). No iguanas are native to Asia, Africa, or Australia. There are 24 genera of orthocerous weevils endemic to New Zealand. Relatives of these weevils are found in New Caledonia, Australia, Sulawesi – and across the Pacific, in Chile. On his journey on the Beagle, Darwin described the fungus genus Cyttaria on Tierra del Fuego and on Tasmania. In New Zealand, three species of the fungus occur. They are C. gunnii, C. pallida, and C. nigra. The distribution of the genus follows the distribution of Nothofagus, which today has 9 species in South America and 5 species in New Zealand. Banksia Ericifolia, The Dog that Did Not Bark A “star witness” to the issue of passage of angiosperms from Australia to New Zealand is Banksia ericifolia, of family Proteaceae. Banksia ericifolia offers testimony to Premise 3, in paraphrase: No natural transfer of cool rainforest trees between Australia and New Zealand resulted from the relocation of New Zealand opposite Australia. If ever there had been an overland passage from Southeastern Australia to New Zealand 250 to 80 million years ago, Banksia ericifolia would have had the abundance and the cold-hardy capability to travel that passage and to flourish in New Zealand. Banksia ericifolia, the hearth banksia, bears the imprint of the Primo- Carboniferous Ice Age in its flowers and in its short, needle-shaped leaves. It is a survivor of a Permian glacial orogenic foray into New South Wales 250 million years ago. 14
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| Thus, it is a living example of how the icy cold of 300 to 250 million years ago altered the angiosperms that were just beyond the reach of destruction. B. ericifolia came as close to the glaciers of New South Wales as nature’s chemistry allowed. Ice molded it into an entity hard and frugal. Its husbandry enabled it to retain only the essentials of growth and reproduction. Today B. ericifolia grows in abundance throughout Victoria. It was in high density during the Cretaceous in Southeast Australia, where its needles were probably a prime source of nourishment to the cold-adapted members of the dinosaur infra order Ornithopoda, dominant among the Cretaceous herbivore dinosaurs of Australia. Like other Proteaceae, B.ericifolia trees favor coastal hillsides on the flanks of the ancient Great Dividing Range. Long years ago, they looked down on the cold water that separated Australia from that advent New Zealand Plate that, perhaps 260 million years ago, seemed to have moored offshore. Surely they could have made that polar passage from Australia to New Zealand, had there been an opportunity. They stood by to watch as 80 million years ago the widening Tasman Sea took away any further hope of overland passage. There is no record of endemic Banksia ericifolia in New Zealand. Hence, here is a star witness that an overland passageway never existed from Australia to New Zealand. Negative evidence as forthright evidence? In “The Hound of the Baskervilles,” the key evidence was provided by the dog that did not bark. Part 4: Mammals, in Crucial Support of New Zealand as a Part of South America Absence of Mammals from New Zealand For mammals, as well as for ancient rainforest trees, Premise 3 of no overland passage between Australia and New Zealand applies highly significantly. The beginning of the Carboniferous likely marked the beginning of the land reptile; and as the period ran its course, mammal-like reptiles known as therapsids came upon the scene. Later, the mammalian lineage emerged – roughly 300 million years ago. At the close of the Carboniferous 280 million years ago, both monotreme and marsupial mammals roamed Gondwanaland. Eutherian (placental) mammals may have begun to evolve at that time. “New Zealand was home to only three land mammals before the arrival of the [aborigines some 46000 years ago], and all were bats,” according to T. Flannery and P. Schouten in 2001 (17). And in an earlier discussion by T. Flannery in 1995 (18): “The New Zealand wattled bat [Chalinolobus tubercalatus] is the only New Zealand mammal with Australian affinities . . . ” Not one marsupial present there on New Zealand, or, as it follows, not one on New Caledonia! 15
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The dates tell the story. There is considerable evidence that the New Zealand Plate rifted from South America about 280 million years ago – about the time that the earliest mammals were just coming into existence. Hence, there were no mammals other than flying mammals on New Zealand before the coming of man. Equally significant, from the time of approach of the New Zealand Plate to Australia about 260 million years, Australian marsupials never made direct passage to New Zealand, (or indirectly by way of New Caledonia). Except for flying creatures and effects of mankind, there has been “total non-connect” of mammals between Australia and New Zealand. The above-stated absence of monotrimes, marsupials and placental mammals from New Zealand is prime testimony that 1) these animals never crossed over from Australia or from other parts of Gondwanaland to New Zealand and 2) Australia and New Zealand were never connected for overland passage. Part 5: Dinosaur, Bird, and Inter-island Aspects Were There Dinosaurs in New Zealand? The dinosaurs came into existence about 230 million years ago (during the Triassic). The dinosaurs raise a moot question regarding New Zealand: Did they ever come to New Zealand? From Australia? Even by way of New Caledonia about 100 Ma? It is doubtful that there was ever a native presence of dinosaurs in New Zealand. It is doubtful, even though dinosaur nesting sites with theropods, ornithopods, and ankylosaurs undoubtedly existed at Dinosaur Cove in Southeastern Australia (in Victoria) about 115 million years ago – but at an extreme sea-travel distance from New Zealand, even for an aquatic reptile such as a dinosaur. A few bone fragments of theropods, ornithopods, and ankylosaurs were found in a stream bed at Hawkes Bay, off North Island, about 1980. There appears to be no exacting authentication whether these few bone fragments were brought by nature to that stream bed at a tourist haven; or, in conjecture, whether there may have been a transplant, perhaps from Dinosaur Cove. This thesis is not aware of any explicit dinosaur nesting sites or of any sequence of dinosaur bone discovery and recording by a professional paleontologist in New Zealand. 16
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| Basic
Distinction among Birds It would be remiss not to mention that there is at least one flightless bird that traversed the briny deep from Australia to New Zealand. It is the penguin – prodigiously-long-distance swimmer. It is at home today in the coastal waters of New Zealand. There are seven species on New Zealand shores. Most well-known is Eudyptula minor, the fairy penguin. Flying birds evolved from flightless birds of theropod descent. A very early stage of bird evolution – a stage from feathered theropod to flightless aquatic bird – goes back about 145 million years ago to the late Jurassic. Fossil records of 50 million years ago indicate a large penguin and another large flightless bird, the great auk. True flightless birds, neither one ever flew. The latter, recently extinct, was patriarch of the bird family Alcidae, about 21 living species, all of them illustrating a smooth transition from flightless to flying bird. Like the penguin, they all are prodigious swimmers. Attention is given here to the true flightless birds because they are in sharp distinction to the ratites – the kiwi and the unrelated extinct moa – natives to New Zealand. Ratites are ground birds that evolved polyphyletically on ecological opportunity from birds capable of flight. The ratite amply illustrates a course of evolution in birds, of different families, that had already evolved flight capability. The trend to flight is reversed in birds where food is plentiful upon the ground; nesting on the ground is relatively safe; and there is danger on the wing from predators. Under such conditions, the body tends to lose its streamlines; wings become abridged; and flight becomes short and eventually is lost. The precursors of the kiwi and the moa flew to New Zealand, perhaps from Australia, perhaps from elsewhere – and found it hospitable. Inter-island Biotic Commonality It is relevant to emphasize the close biological relationships among the islands themselves that stem at least partially from New Zealand. On New Caledonia, Proteaceae consociate with Nothofagaceae and with the conifer Araucariaceae. On New Zealand, Nothofagus and Agathis, sister genus to Araucaria, are together in mixed stands, with Proteaceae nearby. Both Fiji and New Caledonia have Podocarpus forests. Two Proteaceae genera are Knightia and Kermandecia. On New Caledonia, there are two native species of Knightia, the honeysuckle tree; on New Zealand, there is one. On New Caledonia, there are two native Kermandecia species; on Fiji and Vanuatu, there is one each. The genera are native nowhere else. 17
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| There is a large bulimoid
snail,
Placostylus, prominent in New Zealand, Norfolk Island, New Caledonia,
Fiji, Vanuatu, and the Solomon Islands, and where land appears on Lord
Howe Rise. Australia and the Louisiades have none. Species are
numerous on Fiji, but Samoa has none. The distribution is said to be in
no way connected with trade winds or ocean currents. On New Zealand, on both North and South Islands, is found a single species of an achlorophyllous root saprophyte, an angiosperm of the family Balanophoraceae. It is Dactylanthus taylori and is found nowhere else. On New Caledonia is found a single species of Balanophoraceae. It is Hachettea austrocaledonia and is found nowhere else. The two species are so closely related anatomically that it has been recommended they be placed in a separate family of their own, the Dactylanthaceae. As indicated by their long isolation, they are probably older than other Balanophoraceae. (Their imputed ancient ancestors, the Amborellaceae, described below, are now found only on New Caledonia.) Sole Small-Island Habitations of Significant Ancient Flora and Fauna It is startling that among the candidates for the badge of most ancient angiosperm tree one is solely in New Caledonia and another, solely in Fiji. One of these is Amborellaceae, a single species, Amborella tricopoda, found only on New Caledonia. It has been specifically cited as the most ancient angiosperm and is considered to be the ancestor of the root holoparasite Balanophoraceae. And there is found only on Fiji the family Degeneriaceae, two species, Degeneria vitiensis and Degeneria roseiflora, marked as earliest primitive by their leaf-like, three-veined stamens and their carpels. How strange that each among the oldest is found isolated on a separate small oceanic island! How out of biological and tectonic context it must seem -the one, only on New Caledonia; the other, only on Fiji! They could hardly have been imported. The tuataras belong to the order Rhynchocephalia, a sister to Squamata, the large, world-wide order of lizards and snakes. Hook-nosed and lizard-like, the Rhynchocephalia are well-noted in the ancient fossil record. They are represented today only by the two tuatara species on tiny islands. They are Sphenodon guntheri and Sphenodon punctatus. They are native to tiny Lady Alice Island and Stephens Island in New Zealand. There they find shelter from mammal predators. They are found nowhere other than in New Zealand. How much out of biological and tectonic context are the two species of tuataras? 18
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| Conclusions Three premises of the thesis of late-Paleozoic origin of the angiosperm and gymnosperm have been presented herein. They are restated, in paraphrases below, so that the reader may ponder drawing his or her own conclusions. As Immanuel Kant wrote in 1784, “Have courage to use your own understanding.” 1. Cool temperate rainforest angiosperm and gymnosperm trees were conveyed forth on a “New Zealand Plate” rifted from southernmost South America in the late Paleozoic, probably during the Permo-Carboniferous Ice Age, leaving close family members behind. 2. Ferried to the vicinity of Australia on the New Zealand Plate, these ancestral angiosperms and gymnosperms have become today living, though ancient, tree species of New Zealand and New Caledonia, Fiji, and Vanuatu. 3. No significant natural transfer of said rainforest trees between Australia and New Zealand appears to have resulted from the relocation of the New Zealand Plate offshore of Australia. The many observations of affinity of ancient biota to both southernmost South America and the islands of New Zealand, New Caledonia, Fiji, and Vanuatu are a powerful voice that New Zealand was once attached to South America. Highly significantly, the New Zealand absence of Australian marsupials and placental mammals (excepting bats) proclaims that there never was an overland passage crossable from Australia to New Zealand. L’envoi: This voyage of Discovery Ofttimes on perilous seas Unfurls an unexpected sail In wonderment and beauty. –Dedicated to J. D. Hooker 19
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References 1. Troitsky, A.V., Melekhovets, Yu. F., Rakhimova, G.M., Bobrova, V. K., Valiejo-Roman, K.M., and Antonov, A.S., Angiosperm origin . . . deduced from rRNA sequence comparisons, J. Mol. Evol.32 (3), 253-61, (1991). 2. Martin, W.F., Lydiate, D., Brinkmann, H., Forkmann, G., Saedler, H., and Rudiger, C., Molecular phylogenies in angiosperm evolution, Mol. Biol. Evol. 10 (1), 140-162 (1993). 3. Samigulin, T. Kh., Martin, W.F., Troitsky, A.V., and Antonov, A.S., Molecular data from the chloroplast rpoC1 gene suggest a deep and distinct dichotomy: gymnosperms (including gnetales) and angiosperms, J. Mol.Evol.49 (3), 310-315 (1999). 4. Chaw, S-M., Parkinson, C.L., Cheng, Y., Vincent, T.M., and Palmer.J.D., Seed plant phylogeny inferred from all three plant genomes, PNAS 97, 4086-4091 (2000). 5. Bowe, L.M., Coat, G., and dePamphilis, C.W., Philogeny of seed plants based on three genomic compartments, PNAS 97, 4092-4097 (2000). 6. Darwin, C., The Origin of Species: By Means of Natural Selection, Chapter VIII, Random House and others. 7. Hooker, J.D., The botany of the Antarctic voyage of H. M. Discovery ships Erebus and Terror in the years 1839-1843, under the command of Captain Sir James Clark Ross, in Flora Tasmaniae, 3, ~1859. 8. Hoernle, K., Mortimer, N., Werner, R., and Hauff, F., (Eds.) (2003) FS Sonne, Fahrtbericht/Cruise Report SO168 Zealandia “Causes and Effects of Plume and Rift-related Cretaceous and Cenozoic Volcanism on Zealandia,” Geomar Report 133: 127pp+. 9. Windley, B., The Evolving Continent, John Wiley and Sons, West Sussex, 1995. 10. Wood, R. A., ABLOS Monaco report, “Finding the Continental Shelf – Examples from the New Zealand Region,” ABLOS 01Folder/Wood. 11. Tarling, D. H., Personal communication to H. Levin, Sept. 28, 2003. 12. Whitmore, T.C., Phytogeography of Eastern Tethys in Wallace’s Line and Plate Tectonics, ed. T.C. Whitmore, Claredon Press, Oxford, 1981. 13. Whitmore, T.C., Phytogeography of the eastern end of Tethys, 307-311, in Gondwana and Tethys, eds. M. G. Audley-Charles and A. Hallam, Geological Society, Oxford Press, 1988. 14. Tarling, D.H. and Tarling, M.P., Continental Drift, a Study of the Earth’s Moving Surface, G. Bell and Sons, London, 1971. 15. Gibbs, M.T., Rees, P.M., Kutzbach, J.E., Ziegler, A.M., Behling, P.J., and Rowley, D.B., Simulations of Permian climate and comparisons with climate-sensitive sediments, The Journal of Geology, 110, 33-55, (2002). 16. Quinn, C.J. and Gadek, P., Biflavones in Dacrydium sensu lato, Phytochemistry 20, 677-681 (1981). 17. Flannery, T., and Schouten, P., A Gap in Nature, p. 167, Atlantic Monthly Press, 2002. 18. Flannery, T., Mammals of the South-West Pacific and Moluccan Islands, p. 366, Reed Books, Chatswood, N.S.W |
