SEED DISPERSAL
 The seeds of bulrushes are dispersed by both water and wind. This plant has a mace-like section consisting of thousands of tiny tightly-packed fruits. As the picture shows, little tufts on the fruits allow the seeds to be transported when the time comes. (Grains de Vie, p. 40.) |
In the creation of the heavens and Earth, and the alternation of the night and day, and the ships which sail the seas to people’s benefit, and the water which God sends down from the sky – by which He brings the Earth to life when it was dead and scatters about in it creatures of every kind – and the varying direction of the winds, and the clouds subservient between heaven and Earth, there are signs for people who use their intellect. (Qur’an, 2:164)
Until now, you may never have wondered how plants, fixed life forms that are not capable of movement, manage to distribute their seeds. However, since the time plants came into existence, they have managed to distribute their seeds by various means, without the need for any assistance or intervention. After pollinated flowers form seeds, some of these fall to the ground beside the plant. Other species’ seeds are carried by the wind, or stick to the fur of animals and are distributed in this way. But this summary of seed dispersion systems is quite superficial, for when you get down to the details, you can see that the lives of plants and animals are directly connected in a number of interesting ways.
As you saw in the previous section, each plant’s seed has a different shape. From the shape of a seed or fruit, it’s possible to determine what kind of journey it has made – that is, how it’s been distributed. Some trees, for instance, have fruits that are colorful, fleshy, soft, and pleasant smelling. These trees, whose seed coats are tough enough to be resistant to digestive juices, attract birds and other animals. Other species’ seeds have needles, hooks or thorns that snag and get caught in the fur of animals, who transport them in this way. Still others travel on the wind, like so many feathers. Others have wings or swell like small balloons to help them catch the wind. Such seeds have to be light enough and of a suitable shape for flight. On the other hand, some plants simply let their seeds fall to the ground as the seed case splits as it dries in the sun, while others eject or propel their seeds, through the tension created in the seedpod while the seeds are growing.
From the examples given so far, the creation of a very detailed dispersion system is immediately evident.
The essential point worth noting is the perfection of each method of dispersion, despite all of the diverse structures. The systems never fail. Seeds carried by animals are invariably spread in this way, and the wind always carries those with the appropriate shape.
As the following examples will show, both animals and plants act in a remarkably conscious fashion in the course of these operations. But what is the source of this conscious planning? It’s of course impossible for a flowering plant to get together with a bird or a squirrel and decide to set up a dispersion system, or for these life forms to make a joint decision as to what each will do to operate the system. Plants are incapable of making a reproductive plan or setting up a system according to it. But when the time comes, every plant starts its reproductive operations, produces its seeds and distributes them in the necessary way. Throughout the world, each plant of the same species acts in the same way in the same sequence, using the same system.
Plants with Ballistic Knowledge
For dispersion of their seeds, most plants require an outside agency – wind, gravity, or animals. But some flowering plants propel their seeds into the air when a drop of rain falls on them or when touched. For instance, the seeds of the evening primrose (Oenethera biennis) are stored in capsules which are sealed when dry. When these capsules get wet, they immediately open in the shape of a goblet. In this position, raindrops are enough to distribute the seeds. The henna plant’s yellow, orange and brown speckled flowers can be seen growing at any roadside. When touched, they propel their seeds like a pistol going off. But this raises a very important point. As we know, plants are static life forms, unable to move around. But for them to be capable of propulsion, some form of energy must be required. This energy is activated during changes in the seedpod where the seeds are located. The pods crinkle as they dry in the sun, which generates latent energy. In much the same way, when the seed is moistened by rain, the swelling seedpod creates energy that can be triggered for propulsion.18
In such dispersion operations, finely balanced mechanisms are at work in plants. The timing of the plant’s dispersion of its seeds is also very important, as illustrated by the Mediterranean squirting cucumber.
A Natural Rocket System
Plants like the Mediterranean squirting cucumber generate their own force to distribute seeds. As the squirting cucumber ripens, it fills with a slimy juice, which gradually creates pressure until the cucumber bursts off its stalk. Behind it comes a trail of slime like the trail behind a space rocket. By this means, the cucumber’s seeds are dispersed on the ground together with the slime.19 At first glance, this mechanism seems like a plant just exploding at maturity, but it’s in fact very sensitive. It is of vital importance that when the fruit starts filling with juice is synchronized with the time when the cucumber and its seeds start to mature. For if the system were to operate before the seeds matured, there’d be no advantage in the cucumber bursting. This would prevent the plant from reproducing, and mean the end of the species. But thanks to the plant’s perfect timing, the system starts to function and disperses the seeds at exactly the right time.
This fine timing holds true for all plants that disperse their seeds by propulsion. That this works without a hitch raises the question of how any such system came to exist at all. As we have seen, plants need an integrated system in order to reproduce. It is illogical and unreasonable to claim that this mechanism – which must have been present in each plant simultaneously, from the very start – has evolved as a result of changes taking place over thousands, even millions of years. The maturing of the fruit, the fluid it contains, and the seeds must all emerge at the same time. Any hitch would mean that the plant could not disperse its seeds. Take any component you choose out of this system; the result will always be the same: extinction of the species.
The details that go into the distribution of just a single seed plainly show how perfectly and completely plants have come into existence. This cannot have been achieved through pure coincidence, or random natural events. The obvious truth is that God, the Creator of all things, has created them in all their perfection. There is no other deity than Almighty God. Thus it behooves all intelligent people to live in the knowledge of this truth and to be directed to God in everything they do.
Your deity is God alone, there is no deity but Him. He encompasses all things in His knowledge. (Qur'an, 20:98)
Examples Drawn from Other Plants
The broom is another plant that reproduces by opening its seedpod of its own accord, but in a completely different way from that of the Mediterranean squirting cucumber. The broom’s pods burst as a result of evaporation rather than as a result of an increase of liquid in the plant. As the heat rises, the side of the pod facing the sun dries out faster than that in the shade, which creates a tension in the pod. Finally it splits suddenly into two halves, and its tiny black seeds are dispersed in all directions.20 The seedpod of a tropical tree called Hura crepitans, consists of a dozen small chambers fused together. The seedpods burst noisily in the heat of the sun. After the seedpods pop, the seeds and split pods are scattered in the surrounding environment. Hura crepitans is one of the most successful at propelling its seeds to great distances. When the time comes, it can hurl them up to about a few meters.21
The Geranium’s Effective Propagation Methods
Wherever geraniums grow in the world, this mechanism is perfectly preserved. If this were not so, geraniums could not reproduce, and the species would die out. Obviously this intricate and perfect order has not come into being of its own accord. God, Who has perfectly created all living things on Earth, also created geraniums in such intricate detail.
The Incredible Twisting Mechanism of Erodium
As in the geranium, the fruits of the Erodium plant (stork's bill)come together on their syles at one central point. The seeds are located inside the fruits shown in the illustration. At maturity, the stamen attached to the seed starts to curl, extending towards the ground. This is when the plant’s amazing mechanism comes into play, letting its seeds screw themselves into the soil. The system consists of the following:1-The top of the tail on the ripening seed curls into a vertical position. When the tail is twisting into the soil, it functions as a lever.
2-The bottom of the tail is twisted and screws into the soil, functioning like an engine to drive the seed into the earth. 3-The filaments surrounding the tail are long, closely woven and stick in like thorns, providing support.
4-The head, carrying the seeds inside, is like the pointed tip of a cork screw, driven into the earth by the action of the lever at the top.
5-The hairs on the head, short and regular, ease the seed’s passage into the soil and at the same time, act as a kind of fishhook to prevent the seed being pulled out again.
The big picture to the left shows Erodium seeds anchored to the ground.23
The ability of this soft plant to pierce hard ground is naturally not the product of coincidence. God, Who has no partner in His creation, acquaints us with His art with the system installed in this incomparable plant.
Seeds Dispersed by the Wind
Seeds carried by the wind must be light enough and of a suitable shape to be airborne. For instance, any seed the size and shape of a hazelnut or a coconut cannot take to the air. For this reason, all seeds borne on the wind are very light; and bear feathery or wing-like structures.The great majority of wind-borne seeds have matured by the beginning of autumn, when the winds are strongest. Remarkably, the autumn winds begin just at the time when the seeds mature.
The plants whose seeds are dispersed by the wind differ from each other in their structures, in much the same way as do the plants themselves. For instance, in the North African deserts, fruits and seeds are either winged or light and fluffy. The fruit and seeds of plants of the Nubian Desert in Northeast Sudan and the North American deserts are dispersed by light winds. In the Middle East and North Africa, plants assume a round ball-like shape and in times of drought are dragged around by the wind.24
The dandelion, lettuce, and thistle are a few of the plants whose seeds are dispersed by the wind. Another example is the groundcherry, whose seeds are in paperlike sacs that have air in them and act as small balloons to help them move in the wind.25
An important point to be borne in mind is that it’s impossible for a plant’s reproductive system to change over time. For example, a plant whose seeds are being carried by animals and buried in the ground cannot, over time, become light enough to be carried by the wind. However much time passes, be it even millions of years, a heavy seed like an apricot pit cannot become light and develop wing-like structures. Such a claim can’t be reconciled with scientific logic, because the plants and animals, or any other elements found in nature, do not engage in such planning. The plant is not able to bring about the conscious organization in seeds.
Thinking about these facts, you can immediately understand that seeds have had the features they now possess since they first existed. This is one of the countless pieces of evidence that seeds were created in an instant. There are evident signs of creation in the structures of seeds that let them be transported, and this creation is God's, Who has eternal knowledge.
On examining the air-borne Zanonia seed, engineers who study the principles of flight have discovered some interesting things. They studied its center of gravity, the point around which its weight is evenly balanced. If the center of gravity were moved any further back, the seed would move more slowly. However, thanks to the Zanonia seed’s perfect shape and general structure, the breeze can easily carry it for long distances.26
Dust-Like Seeds
When the seedpods of the poppy and the snapdragon sway in the wind, thousands of fine seeds are dispersed into the environment. These seeds are so small that they look like specks of dust in the air. The upper sections of the pods containing the seeds are pierced with little holes like the top of a saltcellar. In fact, at the beginning of the last century, R.H. France, the inventor of the saltcellar, was inspired by the finely crafted structure of these plants!31
The seedpods of orchids have three compartments. When these pods mature they burst, scattering clouds of tiny seeds that are practically weightless and have no reserve of nutrients. Even the embryo has not developed fully, and so orchid seeds need very special conditions to germinate. But this is no disadvantage, because as many as 2 million seeds may be produced from a single orchid seedpod.32
Fluffy Seeds
Just like the seeds with parachutes, fluffy seeds do not fall straight to the ground. Clematis, for example, waits for the wind to make their mother plant sway and carry the seeds away. Plants like pampas grass with their long, feathery plumes wave in the wind like flags, letting their seeds be carried far by the wind.33Plants growing on the seashore or on riverbanks use the nearby water to disperse their seeds. To achieve this, these seeds must be water-resistant and have very special structures. Waterproof and unsinkable, they are created to be resilient enough to preserve their ability to flourish, even after a prolonged journey in seawater.
The seeds of such plants are rendered waterproof by their thick, glossy outer shells. They are able to float, sometimes due to an air chamber or their airy, spongy structure; or sometimes, as in the case of small seeds, thanks to water’s surface tension.
Coconut palms can be found on tropical shores all over the world. The coconut seed, one of the seeds dispersed by water, is contained in a hard shell to provide safe travel. Everything it needs for its long journey, including fresh water, is contained inside this hard shell. The tough texture of the outer layer protects the seed from the harmful effects of water. One of the coconut’s most interesting features is the air spaces and corky floats that keep it afloat, enabling it to travel thousands of kilometers on oceanic currents. When it reaches the shore at high tide, it lodges in the sand, the seed within germinates and grows into a new coconut tree.34
Coconut is most successful at dispersing its seed by ocean currents. What essentially prevents coconut from sinking is its fiber float, where air gets trapped between the fibers. In addition, its outer shell is smooth, polished and waterproof, characteristics that enable it to remain at sea for months.35
Another of the seeds traveling in tropical latitudes is one of the large legumes, the sea-bean, whose seeds are not as big as those of the coconut and only use rivers for transportation. Their very thick and waterproof outer shells and great longevity make them a most successful traveling plant. Thanks to the air chambers in the seeds, they do not sink in the water. 36
The seeds of sea heart (Entada gigas), a tropical African sea-bean, have an interesting heart shape. The seeds grow inside the seedpod, which is of great dimensions. Violent rain can carry seeds of this plant, which grows on the banks of rivers, as far as the Atlantic Ocean, where they go on journeys lasting for years and reach places as far as Europe, the Gulf of Mexico or Florida.
The seeds of gray nickers (Caesalpinia bonduc) can also travel long distances on sea currents. This small, round gray seed does not sink, thanks to an air chamber under its thick coat. It can stay at sea for years without losing its ability to germinate.
Another plant whose seeds are dispersed by water is the sea daffodil (Pancratium maritimum). This plant, found on sandy Mediterranean and Atlantic shores, is distributed by means of its angular black and incredibly light seeds, which are enclosed in a seaweed-like casing.37
The tiny seeds of plants like nasturtium (Tropaeolum majus) are covered in a hydrophobic polish that lets them make use of surface tension to keep from sinking. By this means, the seeds are able to travel by floating along rivers.38
Seeds distributed by water are formed so as to reduce their weight and increase their surface area. Air-filled buoyant structure is usually found in fruits and seeds. Their floating tissue can take a variety of forms, but is likely to be a spongy structure with air-filled cells, or a structure of tightly packed cells that traps air inside. In addition, the cell walls have to prevent the entry of water, and there must be an inner layer to protect the plant’s embryo and its genetic information.39 This evident arrangement in seeds is just one of the countless pieces of evidence of God’s creation on Earth.
As seen from the examples in this section, the most important characteristic of seeds transported by water is that they germinate once they get to land. This is an exceptional situation, because as we know, seeds usually start to germinate when they come in contact with water. However, plants using water to disperse their seeds are different in this respect thanks to their seeds’ special structures. If these seeds were to start germinating as soon as they came into contact with water, their species would have died out long ago. However, thanks to mechanisms suited to the conditions they live in, these plants can perpetuate themselves with ease.
All plants on Earth enjoy the structures most suited to them, with exceptional characteristics unique to each species. Why are the features of every kind of plant in perfect harmony with its environment? And how did such features come into being?
Taking plants that disperse their seeds by water as an example, we see once again evidence that these species couldn’t have appeared by chance. For the seeds of these plants to remain viable in water for so long, they need to be more resilient than average, with casings that are quite thick and special structures to protect the embryo from water. Obviously, such structures are not formed by coincidence, much less by the plant’s own efforts. On their long journeys, moreover, the seeds will need more nutrients than usual and exactly the right amount of nutrient is installed in them. Evidently this characteristic could not occur by chance. It is evident that chance could not calculate the amount of nutrients a plant needs for its journey and then provide the seed with exactly that amount. In contrast to all other plants’ seeds, these do not germinate in water, but as soon as they come into contact with land. Such timing could not possibly be achieved by coincidence.
All these delicate calculations and measurements are carried out to perfection by God, the Creator of seeds, Who knows all their needs and characteristics. He has eternal intelligence and knowledge. A verse of the Qur’an tells how God has created everything in due measure:
As for the earth, We stretched it out and cast firmly embedded mountains in it and made everything grow in due proportion on it. (Qur’an, 15:19)
Plants that Get Others to Disperse Their Seeds
As you wander through long grass, the seeds that stick to your clothing or your dog’s fur have special structures that let them be carried in this way. To cling to animate objects, some of these seeds use needles, hooks, tacks and thorns. Other species have attractive smelling, colorful or tasty fruits, as though they are decoratively created in terms of color, smell, shape and presentation, to entice animals into carrying them away. The fruits, which are rich in sugar, water, energy and mineral salts, are attractive to animals that eat them, thus helping proliferate plants by dispersing their seeds over a very wide area.
Mistletoe (Viscum album) stays green all through winter when its host trees have all lost their leaves. Throughout the winter season it produces small seeds that usually germinate on the trunks and branches of other trees rather than on the ground. So how is this done?
The seeds have to cling to a branch of a host tree and not fall to the ground if they are to germinate. But under normal circumstances, the rounded seeds would fall directly to the ground. This problem is solved for the mistletoe seeds by the thrush, which is very partial to mistletoe seeds. This is very important, because in order for the plant to reproduce, its seeds must pass through the thrush’s digestive tract. In the belly of the thrush, the seeds are coated in a very effective substance called viscin, which, after passing out of the bird’s body, bonds the seed to the host. In this way, a new parasitic plant starts to germinate. (Grains de Vie, p. 47.) It is quite thought-provoking that reproduction in the mistletoe is linked to the thrushes’ love for its berries. Obviously this association is no coincidence. Mistletoe has used this method of propagation since it first existed, for this is how it has been created. It is God Who makes the two life forms aware of each other.
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The strangler fig tree, native to Borneo, shares its life with a kind of wasp. The figs provide an ideal safe shelter for the wasp’s eggs. In return, the wasp helps pollinate the fig by carrying the tree’s pollen.
Strangler figs mature at the same time as the larvae of the wasps. After weeks, male and female wasps hatch from the eggs. The male bites a small hole in the flower's ovary wall. He then inseminates the female through the hole. In the male wasp’s short life, his last duty is to open an exit tunnel for the female, and he usually dies as soon as he reaches the surface. The female wasp is then able to leave, and flies to another tree, carrying pollen from her host tree. She enters a ripe fig through an opening at the bottom. In the process of laying her eggs in the ovaries of the flowers, she pollinates the long-styled female flowers. When the female wasp has done her duty, she too dies.
After a time, new wasps hatch from the eggs she’s laid, and leave, covered in pollen, by the tunnel previously opened by the male wasp. And to perpetuate the reproductive chain they move on to another fig. (National Geographic, “Borneo’s Strangler Fig Trees,” Tim Laman, April 1, 1997, p. 41.)
The wasp can’t possibly have invented such a complex method of its own accord or taught others how to do this. It is perfectly obvious that the fig’s reproductive system has been specially created to live in cooperation with the wasp.
This shows once again that this system has been created by God and that wasps act according to His inspiration.
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Symbiotic Relationship between Ants and Plants
As just mentioned, some plants’ reproduction depends on animals to carry their seeds. This shows an interesting harmony between plants and animals. To illustrate, let’s take a seed covered in an oily, edible tissue, called an eliasome. This tissue, seemingly quite ordinary at first glance, actually plays a vital role in the plant’s survival, for it is the reason why ants are interested in the plant and play a role in its proliferation. As with almost every other seed, this one must also go underground in order to germinate, and to make germination happen, the core of the seed must be exposed. The plant cannot do this by itself, but ants can. To them, the oily covering is a very attractive food, so they collect the seeds with great zeal and carry them to their nests. Thus initially, the seeds are carried beneath the soil.
Then begins the second important stage for the seeds. Having spent lots of effort to carry them to their nest, the ants gnaw off the eliasomes and abandon the seeds themselves. In this way, the part of the plant that allows for reproduction reaches an ideal position underground.41
So how did this harmony between ant and seed emerge?
Of course, that the ant does this consciously, acting in knowledge of what the seeds need to sprout is an untenable idea. And it’s completely unreasonable to theorize that the ant discovered the seed by accident one day, took it underground and, seeing that it grew into a plant, informed the next generations of ants that they should do the same thing. It’s equally preposterous to claim that somehow, the plant learned what this species of ant likes, and tailored its seeds accordingly in order to reproduce.
This harmony must have been specially arranged, because this plant’s very first seeds had no other mechanism by which to reproduce. If it hadn’t been able to attract the attention of ants, there would be no likelihood of its continued existence. (And if the ants didn’t exist, they would have no way to survive.) But the reality that this plant's existence shows us is plain to see. The consciousness behind this perfect harmony is neither the plant’s nor the ants’. The supreme source of this consciousness is God, Who knows the characteristics of these two life forms and has created them in harmony with each other. God makes known how every living thing is submissive to Him in a verse of the Qur’an:
Everyone in the heavens and Earth belongs to Him. All are submissive to Him. (Qur’an, 30:26)
The Symbiotic Relationship between the Agouti and the Bertholletia Tree
The seeds of South America’s bertholletia tree, or Brazil nuts, are enclosed in a large round capsule, which, after falling from the tree, lies on the forest floor and remains intact for a time. This is because it has little attraction to many animals; it has no smell, is very hard to break, and there is nothing remarkable about its appearance. But for the nuts inside the capsule to sprout, they must somehow be removed and buried in the soil. Yet none of this is a problem for the bertholletia tree, because living in the same habitat is a creature with the necessary characteristics to get round these obstacles.
The agouti, a South American rodent, knows that there’s something edible inside the thick, odorless capsule. Agoutis’ sharp, pointed teeth can easily break through the hard shells. In every capsule there are about twenty nuts, far more than an agouti can eat at one sitting. So a satisfied agouti carries the nuts in its cheek pouches and digs small holes to store them in and covers them over, much as a squirrel does with acorns. Even though the agouti does this with the intention of eating the nuts later, it never does locate a considerable proportion of the nuts it buries. In this way, the majority of the bertholletia tree’s large heavy seeds are distributed to germinate in the earth.42
The feeding habits of the agouti and the propagation system of the bertholletia tree are remarkably well suited, but this compatibility is not the result of coincidence. These living species have not discovered one another by accident. The bertholletia tree can’t afford the luxury of waiting for such an unconscious coincidence to happen, because this tree has been dependent on the agouti to propagate since the very first day of its existence. It follows that these two species have been created to be compatible with one another.
To clarify this situation with an example, imagine a television with a remote control on the table beside it. You pick up the remote, switch on the TV and flick through the channels. Probably you would assume that the remote control has been designed to control the TV. But what if someone else enters the room and says, “This remote control and the TV have evolved over time as the result of a series of coincidences, and eventually – also by chance – they’ve become compatible.” You’d probably suspect that this person had taken leave of his senses.
Yet the relationship between the bertholletia tree and the agouti is far more complex than between a television and a remote control. The systems of both living species have been organized to be mutually beneficial. And where there is organization, naturally, there is an Organizer.
These living things have been created by one Creator, God. This harmony, just one of the countless examples in nature, is undoubtedly the product of a supreme intelligence. In His unbounded wisdom, God has created these two life forms together with these characteristics.
There is no creature on the Earth which is not dependent upon God for its provision. He knows where it lives and where it dies. They are all in a clear book. (Qur’an, 11:6)
Fruit-eating birds have no gizzards and accordingly they do not use pebbles to grind their food. This feature is extremely important, because were the seeds ground in the bird’s alimentary tract, they would be destroyed and plants might become extinct. But birds without a gizzard can carry the seeds and let them germinate. Between birds and plants, a symbiotic relationship exists. The plant’s seeds are carried by the bird, which it nourishes in return. (Grains de Vie, p. 49.)
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