What (or who) is a nut?
So far in this book we have looked at how plants spread and change, and at the evidence for the occurrence of Continental Drift and Earth Expansion. Now we will combine these two diverse topics, to provide a new approach to determining specific details of these movements of the Earth's crust, using first as an example the area of nut trees.Because the term 'nut' is applied to a whole range of different plant structures, occurring across almost the whole gamut of plant life, nuts are a useful starting point for this work. To the botanist, 'nut' has a much more specific meaning than the general understanding. What we call a nut may be a seed, a fruit, a tuber (tiger nut), a bulb (water chestnut), a pod (peanut), or any one of a range of specialized plant structures to the botanist.
Nuts not only grow on trees, they grow underground, under and on top of water, in giant gourds on 30-metre vines, in jungles, deserts, everywhere from the tropics to within the arctic circle. Examples of things called or treated as nuts occur in most of the main plant families, and appear in both the gymnosperms (conifers) and both branches of the angiosperms (broadleaved plants). Even the ginkgo, that strange fossil half-way house between them, is a nut producer.
In Fig. 4.1 is shown a world map giving the present distribution of the Proteaceae, the plant family containing the macadamia nut, the avellano, and some other less well-known nuts. The dark parts show heavy concentrations of species, the lighter shading the more lightly populated areas.
Now remember the principle (Proposition 3A) that species that are related must have had common ancestors existing in a single range. The only way for the current distribution of the Proteaceae to have come about, is for the species to have spread naturally by their inbuilt dispersal mechanisms (the conventional view), or for the areas of population to have been in contact with each other in the past and since moved apart through continental drift, or a combination of both.
The Continental Drift approach, which is not disputed at this time, provides a satisfactory broad-scale explanation. The continents involved are the same southern ones as those concerned with the Glossopteris fossils (Fig. 3.2). Notice, however, that the modern Proteaceae extend beyond the range of the Glossopteris fossils, and in particular exist all over southeast Asia and up into southern China.
As the rocks containing the Glossopteris fossils are now widely separated, then using the principle of Continental Drift it was only natural to assume that these rocks were in continental masses which had drifted apart, and it was not hard to suggest how they had once fitted together (Fig. 3.2).
Now look at Fig. 4.2, the distribution of species of true pines (Pinus), containing many nut-bearing trees. Notice that this map more or less complements the first one; there are only small areas of overlap, in Central America and the Malesian area, and these are well within the range of what might be expected from natural dispersion.
The distribution of pines is paralleled also by that of the oaks, species of Quercus and some close relatives. People with European connections tend to think of oaks as a typical European tree, but in fact there are two areas with high concentrations of oak species. One is in the USA/ Mexico region, the other is in southeast Asia. In spite of this, native oaks are completely lacking in the adjacent areas of Australia and South America, just as with the pines.
We will see later on that this situation is repeated with many other plant families. The explanation is fairly obvious at this point -- the Proteaceae developed in Gondwanaland, and the pines and oaks in Laurasia. This is an unremarkable continental drift implication.
Proposition 4A
Plant families tend to be identifiable either with Gondwanaland
or with Laurasia
Now to move on to some detailed distributions. First, in Fig. 4.3, we see the distribution of species of Elaeis, the oil-palm, and a major world source of oil from its kernels and fruits. In view of the accepted former juxtaposition of Africa and South America, this distribution is entirely as might be expected.
In Fig. 4.4 we have the map for the Araucarias, sources of those excellent nuts the Bunya Pine in Australia, the Monkey Puzzle in Chile, and the Parana Pine in southern Brazil. Another species is the Norfolk Island Pine, and there are also species in New Guinea. The inference from this map is that eastern Australia once fitted against the west coast of South America, and if you try it with a model, you will find that this match is a very good one.
This distribution is our first hint that the 'basic' continental drift theory requires modification. No conventional reassembly of the Earth on a sphere of current size (eg Fig.3.3) places Australia against South America; in fact the plant distributions show that this link is both strong and relatively recent.
Proposition 4B
Plant distributions are evidence that the Expanding Earth
proposition represents the situation better than the simple
Continental Drift theory
The next map (Fig. 4.5) shows where the three species of Gevuina exist, in Chile, eastern Australia, and New Guinea. The Chile species produces the Avellano or Chile Hazel nut, and the Queensland species also produces an edible nut [44]. These two species are some 13,000 km apart, about one-third of the distance round the planet. It would be hard to explain this as chance dispersal, say by drifting on ocean currents.
The distribution of Adansonia, the boab or baobab family, is shown in Fig. 4.6. There is one species in Africa, extending to India (supposedly introduced by Arab traders!), and one in northwest Australia. But the real concentration is in Madagascar, which has around 12 species. The distribution suggests that Western Australia was once in contact with the east coast of southern Africa, or possibly both were linked through Madagascar or India.
The next map (Fig. 4.7), the distribution of the Canarium family (which contains the pili nut and the java almond), again links Madagascar with Africa (at a more central spot) and with the areas of southeast Asia, the Malesian archipelago, and northern Australia. The range extends well out into the islands of the Pacific.
Similar links, displaced somewhat to the south, are shown by the distribution of Santalum, the Sandalwood family (Fig. 4.8). The focus of the family is in Australia, and it includes the Quandong, a native West Australian nut. Important former sandalwood sources are in India, Timor, and in Hawaii; there is one species in New Zealand, and there was one on the tiny Juan Fernandez islands right across the Pacific off the coast of Chile. There is also a close relative, once classed in Santalum but now given its own species (Colpoon), in the Cape area of Africa.
Links between central Africa, Madagascar, the Malesian islands, northern Australia, and Central America are shown by the range of Omphalea (Fig. 4.9), which contains many edible nuts such as the Jamaica Cobnut, and the Candoo nut from Queensland [44]. The range extends some 28,000 km. It is a relatively narrow, long strip, stretching almost three-quarters of the way around the planet -- a shape virtually impossible to explain by mechanisms such as winds and ocean currents.
It is appropriate here to make another point. When you take into account the relatively fast rate at which plants evolve and genetically diverge (Propositions 2H, 2I), you have the implication that the whole of the Pacific has opened up very quickly and in relatively recent geological time. The links across the Pacific demonstrated here are, in fact, much stronger than those which exist across, say, the south Atlantic.
Proposition 4C
The Pacific Ocean is a relatively recent formation, and was
largely created after the initial formation of the Atlantic Ocean
All the last seven species were ones with southern distributions. It appears that all developed in the southern 'supercontinent' of Gondwanaland, which included South America, Africa, Australia, India, and also Southeast Asia and Southern China. All fall within the current range of the Proteaceae (Fig. 4.1).
Proposition 4D
Gondwanaland included much of southeast Asia and
southern China
The next map, showing the Pistacia family (Fig. 4.10), takes us into the northern supercontinent, Laurasia. As well as the pistachio nut and its relatives native to Central Asia, the Mediterranean area, and the Middle East, there are other species in Burma, China, and the Atlantic islands over to Mexico, Texas, and Guatemala. The range confirms the former contact of Europe and North America, and is in no way unexpected.
Figure 4.11 illustrates the range of Carya species, the pecan and hickories. Almost all of these are in North America; however, a few little-known species are wild in China and the eastern Himalayas. The range confirms the former connection of North America and Asia across what is now the North Pacific.
Figure 4.12 shows the range of the evergreen chestnuts, Castanopsis. They are almost all in Southeast Asia, around 100 species, with just two isolated species way across the Pacific on the west coast of the United States. If you think this could be due to ocean currents, consider that in both parts of the range, Castanopsis is a hill or mountain species which avoids seacoasts.
The maps for Carya and Castanopsis demonstrate that the links across the south Pacific are matched by ones across the north Pacific as well; Laurasia must have been wrapped round on itself too, as well as Gondwanaland.
The next map (Fig. 4.13) shows the distribution of cycads, the zamia palms common to areas which once formed part of Gondwanaland. Their nuts, after treatment to remove toxins, once formed part of the diet of the Australian aborigines. The cycads are a very ancient plant family, and their ancestors are known to be of world-wide occurrence from abundant fossil remains.
The implication of the map is that the modern species are not just those which happened to survive from a former world-wide distribution. It may be that they are closely related, all coming from a common ancestor which achieved an evolutionary step, somewhere in Gondwanaland, which enabled it to adapt to changing conditions, while its relatives became extinct. This particular distribution has a number of other implications which we will return to later.
Finally, the fascinating story of the coconut and its relatives. It is often possible to determine the original home of a species which has been widely dispersed from such things as the number of insects specific to it, or occurrence of close relatives. The coconut has baffled and confused researchers in the past [26; 29] because there is strong evidence that it is a native of Southeast Asia (Fig. 4.14). There is also strong evidence that it is native to the West Coast of northern South America. You can see now that both claims are right -- its area of origin was split apart by Earth expansion.
Fig. 4.14. Distribution of Cocos, Jubaea, and Jubaeopsis
The true coconut has some very interesting non-tropical relatives, the Pygmy Coconut from Chile (Jubaea), and the Pondoland Palm (Jubaeopsis) from Cape Province in South Africa. Their fruits are just like tiny coconuts, complete with the three eyes, and with a little 'milk' inside. They are very distinctive indeed, and although it is now extinct, what was almost certainly a close relative has been found as a fossil in North Auckland, New Zealand (Fig. 4.15). These 'fossil coconuts' are believed to be about 16-17 my old [35] -- another indication that the separation of New Zealand from South America may not be so very old.
Fig. 4.15. Modern Jubaea nut (left) and fossil 'coconut' from New Zealand
These interesting distributions are all readily explicable on the assumption that the current land areas of the Earth were once all physically linked, capping the whole surface of a much smaller sphere. The Earth has since expanded under this cap, which has split into parts which have become separated and, in some cases, moved relative to one another.
Proposition 4E
The Earth's current continents were once all joined together
to completely cover the surface of a much smaller sphere, which
has since expanded
In the next article we will go on to examine some of the details of this process. For the moment, we will just note that the 'unexpanded' Earth must have had less than 60% of the current radius. More detailed work suggests the figure was closer to 50%, a half-radius Earth.
If you find this Proposition hard to swallow, you should ask yourself, is there a better one? Certainly current explanations for such things as the close cross-Pacific links -- usually based on hypothetical land bridges across the Bering Straits during glacial times -- do not stand up to any sort of close scrutiny.
It is quite inconceivable that tropical Asian plant genera could migrate all the way north up the Bering Straits, pass over them when they were much colder and covered with more ice than now, then migrate down again to the American tropics, leaving no trace of their passage. And it is equally inconceivable that they could do this so quickly -- the last glaciation ended only about 10,000 years ago, and the start of the Ice Age is not much more than a million years ago.
As Sherlock Holmes said, "when everything that is impossible has been eliminated, then what explanation remains, however improbable, must be the truth". We will go on to demonstrate that these explanations are not even improbable, but are supported by a solid weight of evidence.
(Full list of references at NURefs)
[26]. Alphonse De Candolle. Origin of cultivated plants. Kegan Paul, London, 1886.
[29]. D R A Eden. The quest for the home of the coconut. South Pacif Bull/ July p39-42, 1963.
[35]. J A Grant-Mackie. Personal Communication, 1986.
[44]. Tony Irvine. Nut species of Northern Queensland. West Australian Nutgrowing Society Yearbook/ p26-30, 1980.
[50]. P Maheshwari. Pinus. CSIR, New Delhi, 1971.
[66]. C Venkata Rao. Proteaceae. CSIR, New Delhi, 1971.
NU005 : How The Earth Fell Apart
NU003: Continental Drift And Earth Expansion
Version 1.0, printed edition ("Nuteeriat: Nut Trees, the Expanding Earth, Rottnest Island, and All That...", Planetary Development Group, Tree Crops Centre, 1989).
Version 2.0, 2004, PDFs etc on World Wide Web (http://www.aoi.com.au/matrix/Nuteeriat.htm)
Version 3.0, 2014 Sep 18, Reworked from Chapter 4 of "Nuteeriat" as one article in a suite on the World Wide Web.
Version 2.0, 2004, PDFs etc on World Wide Web (http://www.aoi.com.au/matrix/Nuteeriat.htm)
Version 3.0, 2014 Sep 18, Reworked from Chapter 4 of "Nuteeriat" as one article in a suite on the World Wide Web.