It’s not a very satisfying solution, but Aristotle does not help us find a better one. He rarely expresses doubts or speaks of struggles, but almost always projects the confidence of a man who has a grip on the phenomena and a good explanation for them. Sometimes, however, we do glimpse an Aristotle in two, or even three, minds. He seems to be unable to decide whether the porphyrai – the muricid snails of the Lagoon’s muddy bottom – generate spontaneously or not. In spring, he says, the porphyrai gather together and secrete a ‘honeycomb’ upon which the baby snails can be seen crawling. He’s obviously talking about their egg cases but, as with the oyster’s gonads, he doesn’t see that. Instead, in Historia animalium, he suggests that the baby snails generate spontaneously from the mud underneath the ‘honeycomb’. In The Generation of Animals, giving a slightly different account, he suggests that the honeycomb is a seed-like residue which gives rise to baby snails, rather as a plant gives rise to buds. And then, in another passage in The Generation of Animals, he moots the possibility that they might be sexual after all: ‘The only animals of this kind [the ostrakoderma] in which copulation has been seen are the snails; but there has been no visual confirmation of whether copulation results in reproduction’ – more research is needed.
Aristotle’s empiricism is also apparent when he treats insects. He thinks that most animals are spontaneous generators; and it may be supposed that he does not know about complex life cycles at all, but this is not so for, in a beautiful passage, he relates the cicada’s:
The large and the small cicada copulate in the same way, belly to belly. The male inserts himself into the female, not the female into the male as with other insects, and the female cicada has a cleft pudendum into which the male inserts himself. They lay their eggs in uncultivated land, and bore a hole with the sharp point they carry at the rear, just like locusts . . . The cicadas also lay their eggs in the stakes people use to prop up their vines: they bore a hole in the stakes; and also in the stalks of the squill. Their spawn seeps into the ground becoming numerous in wet weather. The larva, when it has grown large in the ground, becomes a cicada-mother [mature nymph] . . . As the solstice approaches, they emerge at night: the covering immediately splits and they become cicadas instead of cicada-mothers. At once they become black, harder and larger and start to sing. In both kinds the males sing but the females do not.
And he adds that, if you flex the tip of your finger near one, it will crawl on to your hand.
TETTIX – CICADA – CICADIDAE
FIGS,
HONEY, FISH
MEMBRAS – PILCHARD – SARDINA PILCHARDUS?
LXXIX
ONCE, AT ERRESOS, I saw a slain tuna. It had been caught far up the coast and was being dismembered on a taverna table: whetting his knives, arms red to the elbow, the proprietor gestured vaguely towards Troy. Aristotle speaks of the fish at length, but evidently did not dissect one, for he says nothing about its anatomy – its hot blood, its heart as big as a child’s, its skeletal struts, precision-milled mandibles and aerofoil fins – the whole astonishing hundred-kilogram, steel-blue, armour-clad, organic killing-machine aspect of the thing. Instead, he speaks of its life.
In the spring, he says, the female thynnos ‘conceives’ or fills with roe. As summer approaches it migrates into Pontos Euxeinos, the Black Sea. Fishermen, spotting the churning shoals from watchtowers, net the glistening bodies at night while the fish sleep. The thynnos spawns only in the Black Sea. As it does so, it becomes lean and spent and infected with a parasite that looks like a scorpion and is as big as a spider, clearly a fish louse of some sort. The young fish grow very fast and in autumn depart for the Aegean’s depths where they hibernate, wax fat and then return to Pontus again.*
All earthly creatures necessarily die. Seeking a vicarious immortality, they therefore reproduce. As Aristotle puts it: they ‘return on themselves’ not as individuals, but as forms. Their life cycles are not autonomous, but are ruled by higher cycles – the moon and the sun revolving around the earth. The moon times the menstrual cycles of women; the sun, veering along the ecliptic, gives the seasons to which all creatures adjust their lives. There is, then, an endless amount to say about when and where animals mate, give birth, hibernate and migrate.
Most animals, Aristotle says, pair in spring, but there are many exceptions. Humans pair and give birth at any time of year, but – a further qualification – men are more ardent in winter, women in summer. And the alkyōn, which appears near the setting of the Pleiades (early November), builds an elaborate nest and breeds at the winter solstice (December), when it is often calm and men speak of halkyonides hēmerai – ‘halcyon days’. He means the Eurasian kingfisher, a winter migrant in Lesbos, whose blue-green flash can often be seen in the marshes and creeks that surround the Lagoon. It’s only a charming coincidence that Linnaeus named the bird for Atthis, the sparkling girl whom, of all her pupils, Sappho loved most.*
THYNNOS – ATLANTIC BLUE-FIN TUNA – THUNNUS THYUNNUS ERISSOS, 2012
An annual procession of fishes spawns in the sea. The first fish to do so, in early spring, are the atherinai (sand smelts) which, when spawning, rub their bodies against the sand. Then, Aristotle says, comes the kestreus (a grey mullet), the salpē (salema) in early summer followed by the anthias (swallowtail sea perch?), chrysophrys (gilthead), labrax (European sea bass) and mormyros (striped sea bream). The triglē (red mullet) and the korakinos, whose identity is unknown, breed towards autumn, as does the salpē again. The maenis (blotched picarel), sargos (white sea bream), myxinos and khelōn (two more grey mullets) spawn in winter. Some fishes spawn at different times of year in different places.*
Shunning extremes, many animals conceal themselves against the blazing Aegean sun or Boreas’ winter blasts. At the height of summer all sorts of animals – snakes, lizards, tortoises, a variety of fishes, snails and insects – disappear. At the setting of the Pleiades, bees hide themselves in their hives and fast so that by winter they are almost transparent. The bear, which has mated in the month of Elaphebolion and fattened itself over the summer months, gives birth and goes into hibernation for three months.* Other animals move to more temperate climes. Aristotle records the raucous vernal and autumnal migrations of the cranes between Africa and the Eurasian heartland.
You don’t, of course, have to be an Aristotle to notice the progress of the year. None of this, however, is a paean to the seasons in the fashion of an Alcaeus, Simonides or Thoreau. Aristotle’s aim is to show how animals adjust their habits according to the seasons to ensure that they can breed, raise their young and get food – the fishes that flood into Pontus all do so because it has richer food and fewer predators than the open sea, and because its sweet spring waters aid the growth of their young. He also wants to explain how each animal kind has a certain comfort zone, how the thermal tolerances of ‘weaker’ animals are narrower than those of ‘stronger’ ones – which is why the quail, a weak sort of bird, migrates in front of the stronger crane, and the mackerel in front of the tuna. Above all, he wants to show how living things depend on the structure of the physical world. Their life cycles naturally echo the cycles of celestial rotations: ‘Nature’s aim, then, is to measure the generations and endings of things by the measures of these [celestial] bodies.’ But nature, he warns, doesn’t always achieve its aim, for matter can be intransigent.
LXXX
THERE IS, BURIED within the structure of his physical system, a threat to the very integrity of Aristotle’s world. Science, he says, is the explanation of change; and the world certainly has change enough to be explained. Storms sweep in from the sea; rains fall, rivers gush. Landslides obliterate, mountains erode, volcanoes erupt. Living things – countless living things – live. By his own account, none of this can be taken for granted. That is because the world has an in-built tendency to stasis. But here I must be more precise for, when I say that ‘the world’ has this tendency, I do not mean that the cosmos as a whole does, but only the part of it that corresponds roughl
y to what we call Earth. It’s the part that Aristotle, with greater precision, calls the ‘world under the moon’.
The root of the problem is elementary. Literally so. The sublunary world is, in Aristotle’s view, composed of four elements. Each element has a natural home in the cosmos towards which it tends to travel and where, having arrived, it rests. The natural home of elemental earth is at the centre of the sublunary sphere; that of water is just above earth; of air just above water; of fire just above air. We’re roughly in the middle of this system, hence we usually see fire and air move up, water and earth down. These elementary tendencies are, for Aristotle, as pervasive as gravity is for us. But where gravity keeps our world together, the elements’ movements threaten to turn Aristotle’s world into an onion. Indeed, to a first approximation, the world does look like an onion – it has a core of earth surrounded by successive layers of water, air and fire. However, were the elements perfectly sorted out – were the world at complete equilibrium – then it would be silent. It would be a world locked in elemental rigor mortis. Life itself would not, could not, exist.
Aristotle sees the problem posed by his theory of elements and proposes an elaborate solution. Something, he argues, must continually deflect them from their natural place of rest; something must stir the sublunary pot. To keep the elements in motion he begins by giving them a cycle. Each element is a combination of two dichotomous sets of more fundamental properties, opposed ‘potentials’: hot v. cold and dry v. wet. Thus elemental earth is cold and dry, water is cold and wet, air is hot and wet and fire is hot and dry. These potentials dictate the possible bi-directional transmutations – fire ↔ earth; earth ↔ water; water ↔ air; air ↔ fire – the cycle is complete.
This elegant scheme cannot, by itself, stop the world from turning into an onion. To cycle through their transmutations the elements must come into contact with each other. So he looks to those celestial mixers, the sun and the moon. As they approach and retreat by day, month and year, they heat and cool the world upon which they shine. The summer sun heats the soil to produce a hot, wet, air-rich vapour that forms clouds that, with the arrival of winter, cool and transform back into the cold, wet, water-rich substance we call rain: ‘We must think of this as a river, flowing up and down in a circle, and made partly of air and partly of water.’ By a similar cause the winds blow too – ‘even the wind has a sort of lifespan’.
Aristotle explains these processes in Meteorology. Much of it is about cycles. It’s an argument against entropy; a model of how the world can both change and persist; of how it maintains its dynamic equilibrium. The surface of the earth, he says, is always changing, but so slowly that we scarcely notice it. During the Trojan war Argos was marshy and Mycenae productive; now the Argive marshes are cultivated and Mycenae is dry. Egypt is also desiccating which is why the Nile has changed its course. Some people, he says, think that such changes show that the earth has been drying out since it was formed, but that’s a narrow point of view. Rather, as one part of the earth dries, another subsides into the sea because its interior parts are continually ‘growing and decaying’. Aristotle is trying to penetrate Deep Time, but his evidence comes from Homer.
All this biometeorology raises the question of how Aristotle conceives the sublunary world. Does he think that it is an organism? Are the meteorological cycles life cycles? Are they for the sake of anything? There is a passage in Physics II, 8 – a much discussed one – in which Aristotle seems to say that the winter rain falls for the sake of the spring crops, implying that the physical world is set up for the sake of the living things that inhabit it, perhaps even for man who, after all, reaps what he sows. In his Meteorology, however, he says nothing of the kind. Its cycles are explained entirely in terms of material and moving causes; final causes appear to be completely absent. The sublunary world does have homeostatic mechanisms that keep it going, but they are much simpler than the cybernetic feedbacks that he invokes when explaining living things. The organic language is metaphorical; the earth does not have a soul. He is trying to convey his sense that the cosmos, the seasons, the elements, life itself, are all in some way a unity; that they are all linked together in their coming to be and passing away: cycles within cycles within cycles.
LXXXI
AS ARISTOTLE LISTS THE spawning of the fishes by the seasons, so Theophrastus lists the blooms. The first flowers of spring are the stock and the wallflower. Then comes the poet’s narcissus, the bunchflower narcissus, the windflower and the tassel hyacinth. These are the flowers that the garland-makers use. The dropwort, the gold-flower, the peacock anemone, the field gladiolus, the alpine squill and all the other mountain flowers come next; the wild rose blooms last, and is the first to end, for its time is brief.
For all the flowers that Theophrastus knows, he does not know what they are for. He sees the stamens and pistils, but does not know that they are a flower’s sexual parts, that pollen is the male seed, and that the glory of their scents and colours exists only to seduce their pollinators. The Loves of the Plants (to borrow from Erasmus Darwin) were unknown to him.
The reasons for his ignorance are, at first glance, obvious. Stamens and pistils are rather small; pollen is smaller yet. Then, too, many plants can be grown from cuttings (a true gardener, Theophrastus is quite a bore on this) and there’s no sex going on there. Perhaps he was also influenced by Aristotle’s definition of a male as ‘an animal that reproduces inside another animal’, which doesn’t even begin to work for plants. When explaining how plants reproduce, Aristotle just asserts that they ‘contain both the male and female principle’.*
Except when it comes to figs. In Historia animalium, Aristotle tells a curious tale:
Wild fig fruits contain what people call psēnes. It starts off as a larva but once the skin [pupal case] has split open, the psēn flies out leaving the fruit behind. It then enters the cultivated fig fruits via their openings and causes them not to drop off. That is why smallholders plant [wild] fig trees close to cultivated ones and attach their fruits to them.
As Asian as sheep, there have been figs in the Aegean since before Homer’s time. These days, as anyone will tell you, the best figs on Lesbos come from Erresos. The groves there are as cool and green and full of life as the surrounding hills are hot and dry and barren. Many fig varietals are grown on the island: apostolatika, vasilika, aspra (white), maura (black), diphora (double-bearing, spring and autumn), but the most famous is the smyrna, named for the city in Asia Minor. It’s the one whose fruit you see in the markets, as big as a child’s fist with midnight-purple skin and crimson flesh.
Aristotle’s cultivated fig could have been any of the ancient cultivars. The psēn is the fig wasp, Blastophaga psenes, which emerges from the fruit, just as he says.* The wild fig, which today is called the ornos, flourishes in riverbeds. The business of tying wild to cultivated figs to ensure their fruiting is called ‘caprification’ since the wild fig is fit to be fed only to goats. Once widespread, the practice is now rare in Greece; on Lesbos farmers simply plant wild and cultivated fig trees in a ratio of 1:25.
All this is clear enough, but still leaves us puzzled. What, exactly, is the relationship between the wild and cultivated figs? And how does a wasp that originates in one keep the fruit of the other from falling? Theophrastus, who came from Erresos and so knew all about figs, discusses these questions at length. He repeats Aristotle’s story and adds a few details such as the fact that the fig wasp has an insect predator, the kentrinēs, probably the parasitic wasp Philotrypesis caricae.* He also gives some hypotheses to explain how wasps keep figs on trees. The details don’t matter – they’re mechanical and quite wrong. More intriguingly, both he and Aristotle consider the possibility that this business of the two kinds of figs has something to do with sex.
In The Generation of Animals, when talking about the sexes, Aristotle returns to figs and says: ‘There is some small difference like this [among the sexes], since even in plants of one and the same kind we find some tr
ees that bear fruit and others that do not but assist in concocting the fruits of those that do. This is what happens in the case of the [cultivated] fig and wild fig.’ Theophrastus gets even closer, for he compares figs directly to date palms. Evidently drawing on an Eastern report by Herodotus or Callisthenes, he says that date palms have ‘male’ and ‘female’ flowers and that farmers assist the formation of dates by scattering the ‘dust’ – pollen, obviously – from the one on to the other. That, he continues, is much like the practice of tying wild figs to cultivated ones, and both are like a fish scattering its milt over eggs.
They adduce the analogy. They come so close to the truth. The two kinds of figs are just different sexes of the same kind. A fig is not so much a fruit as an agglomeration of tiny flowers sealed within a fleshy shell. ‘Wild’ and ‘cultivated’ figs are both Ficus caria, but the first contains both male and female flowers, the second only female; the wasp carries pollen from one to the other. Figs won’t mature without having been pollinated, hence the need for their proximity. Our two Greek scientists toy with the idea. Yet neither just says that plants have sex too.
An object lesson, then, in the dangers of theory. Or is it? Perhaps not. The fig is a protean plant. To fruit, Theophrastus notes, some figs need wasps and the business of caprification that goes with them, but most don’t. ‘Isn’t that strange?’ Yes it is. Some fig cultivars, it’s now clear, require pollination, but others do not for they are asexual mutants, and both types were widespread in the fourth century.* Theophrastus, generalizing from the fact that some figs could dispense with sex, concluded that all figs could do so. No reason, then, to believe that plants need sex at all.
The Lagoon Page 24
