Evolution Encyclopedia Vol. 2Chapter 12
THE CREATOR'S HANDIWORK: THE PLANTS
We often take the plants around us for granted, yet without them we would quickly die. They provide man and animals with oxygen and nourishment. Only plants can make food out of the raw materials of wafer, sunlight, and minerals. Directly or indirectly, the rest of us eat what they produce.
There are so many wonders in plants; wonders to be found in fruit, flowers, leaves, trunk and stems, and roots. As you read, search for just one item that could be made by the random, harmful effects of an occasional mutation:
CROSS POLLINATION Flowers Supply bees with nectar; bees transfer pollen from one flower to another, thus preserving the life of the plant. Bees with their long slender tongues can reach the nectar, which other insects cannot. The tiny bee just bristles with body hairs. As it takes the nectar, those hairs pick up the pollen from the flower's stamens.
Some bee flowers have stamens with special levers, triggers, or piston devices for dusting pollen on some particular spot on the bee. Going from one flower to the next, the bee deposits that pollen at the next flower. On each bee flight, the tiny insect somehow knows never to gather nectar and pollen from two different species. It always confines itself to just one species. In this way, the pollen is always carried only to another flower of the same species.
Some flowers are pollinated by beetles. Several hold the beetles in a trap while the stigmas receive the pollen and the stamens sprinkle a fresh supply on the bodies of the prisoners. Then they open an exit by which the beetle escapes.
The flowers which sunbirds pollinate, stand erect and provide a landing platform. The petals of the flower are shaped into a tube which exactly fits the length and curvature of the bird's bill.
Certain flowers in the tropics are pollinated by bats which eat fruit. So the flowers give off a special fruit-like odor, but only at night. This attracts the bats to come to them.
Some flowers are pollinated by flies. Since flies like smelly carrion, these flowers attract them with similar odors.
When the beetle, Catonia, lights on a magnolia flower, its weight springs a trigger like trap that releases a sudden shower of petals that sprinkle pollen on the beetle's back. Alighting at the next flower, its back rubs against the stigma and the pollen goes onto it. Neither the insect nor the plant devised these things.
When the bee arrives at the Iris, it follows a distinct marked line--a center line--on the iris flower that directs it down to the nectar well in the center. In the process, the bee moves under the drooping stigma which rolls pollen off its back. This stigma is curved downward like a bent finger. Farther on in, its back picks up a fresh supply of pollen from the anther under which it is forced to stand in order to suck up the nectar. Meanwhile, the stigma "finger" has straightened up--so that as the bee backs out, its fresh pollen supply will not be scraped off and thus self-pollinate the flower.
Certain flowers, such as the honeysuckle and petunia, have only a faint odor during the day. In the evening, when certain insects which should pollinate them are out, they produce a powerful scent.
Each flower has a different story to tell about how it attracts insects, provides a "door step" for them, presents guide-line colors leading into the flower, and works out its various arrangements of anther and stigma.
AJUGA PLANT When the locusts move across North Africa, eating everything in their path, they never touch the Ajuga plant. This is because there is a hormone in the Ajuga which is identical to an insect hormone in locusts and most other insects. That particular hormone induces molting, the shedding of the outer coat of skin as the insect grows.
If the locust eats the Ajuga, it will cause him to molt and shed his skin. But, because the Ajuga hormone is five times stronger than that found in locusts, it would pop his skin too fast. So locusts that eat the Ajuga quickly lose the skin around their mouths and they starve to death. Most leave it alone.
FIG AND WASP When California planters introduced the Turkish fig, they found it bore no fruit. The trees were covered with flower buds which dropped off without ripening. The problem was that they had brought no fig wasps for that particular fig tree. American entomologists went to Smyrna in Turkey and brought back the fig wasp for that particular fig tree. They then named the fine-tasting fruit the Calimyrna.
Most experts believe that every type of fig in the world has its own particular wasp. But others say that some fig species do not need wasps (for example, Black mission and Adriatic figs). At any rate, those that do could not survive without their particular wasp. This wasp spends its life pollinating that one type of fig tree. The tree in turn provides a home for the young of the fig wasp.
Here, briefly, is how the female wasp does her work; the story of the male fig wasp is equally complex.
There are two kinds of figs: (1) the male fig (caprifig) which is very small and not for eating. It grows the pollen which produces the other kind of fig. (2) the female fig (the Calimyrna, Smyrna, or Turkish fig), which is so delicious. Because the flower parts of the fig are all inside the fig, there is no possibility that wind could pollinate the flowers. The little wasp must do it, or there will be no figs and when the fig tree dies, it will leave no descendents.
The fig wasp is the size of a fruit fly, about 1 /16 inch [.159 cm] long. It crawls into the fig through a hole in the male fig, and there it lays its eggs. The fig wasps hatch from the eggs, and the young feed upon pollen inside the fig, which itself is odd since most flowers have their pollen on the outside of the flower, not inside the fruit. Then, after mating, the tiny wasps leave their birthplace. They are covered with pollen as they emerge from the fig. The little female wasp must work quickly for it only lives 12 hours. Going from fig to fig, it enters through the small hole at the end, pushing its way through a row of staminate flowers, and comes to rest on a bed of pistillate flowers found in the center of the fig. It is searching for the male fig, so it can lay its eggs, but it enters every fig, thus pollinating the female figs in the process. That is an important fact: the little wasp knows that it must enter every fig it finds, for it cannot tell them apart from the outside; yet once inside, it knows it can only lay its eggs inside the male fig.
The female wasp deposits eggs which hatch into larvae and which, in due time become a new generation of wasps.
These mate with each other inside the fig. Leaving it, they are dusted with pollen from the staminate flowers surrounding the entrance. The fig wasps fly away and search for another fig tree of the same type to repeat the process. They spend their brief lives going from one fig tree to another, pollinating each one, but they never go to a fig tree that is not of the same type. If they did, we would only have one type of fig, but as it is we have several types. No one knows how they manage to find their particular fig tree, and the tiny hole of the fig on that tree.
Wind cannot pollinate figs, for the pollen cannot get inside the tiny hole. But without pollination, there would be no fruit, no seeds, no fig trees. From the very beginning, there had to be both fig wasps and the fig tree with its fruit. Otherwise we would have no figs and fig wasps today.
YUCCA AND MOTH Without a tiny white moth the pronuba moth, the large yucca would die. This desert plant appears like a cluster of sharp swords pointing out in all directions. Out of its center arises the stalk of a bright, beautiful flower that looks something like a white lily.
Hiding in the ground is a small moth which never comes out during the day. It only comes out at night, on a certain night.
The flower, in turn, only blooms at certain times of the year and only at night. When it blooms, immediately the pronuba moths break out of their cocoons beneath the sand.
What brought them out of their hiding places down in the desert sand at exactly that moment? How could a tiny wasp in the ground know that a flower had bloomed? No one knows. Struggling up out of the sand, the tiny female moth flies up into the air and circles around until it catches the scent of the flower, and then goes to it.
Arriving there, the moth, which has eaten nothing for a long time, ignores the nectar but instead goes to the top of the stamens of the first flower and, with its tiny feet, carefully scrapes together a wad of pollen that is three times as big as its head. Holding onto it with jaws and legs (it was born with specially enlarged ones for this purpose),the insect flies to another yucca plant. Backing down into the heart of a flower, the moth pierces a hole with an egg-laying needle (a lancelike ovipositor) and lays eggs among the seed cells in the green pod at the base of the pistil.
Next, the insect climbs to the top of the pistil on that same flower. It has a cavity just the right size to receive the wad of pollen. Carefully the moth stuffs the cavity with the pollen. The top of the pistil looks like there is a funnel-shaped opening within it. Into that opening the moth pushes the pollen. By doing this, seeds will grow at the base of that particular pistil. But it was at that same base that the moth laid its eggs. Some of those seeds will provide food for the baby insects when they are later born. If the moth pushed the pollen into the top of the wrong pistil, its babies would die.
Time passes as the pronuba eggs mature and the yucca seeds ripen. When the moth's larvae (caterpillars) emerge from their eggs, they are surrounded by delicious food. They eat and grow larger. But they never eat all the seeds. Their nutritional needs never require eating all the seeds at the base of that particular pistil.
Then, about two months after hatching, each one cuts a hole through the pod, spins a silk thread, and lets itself down to the ground. Arriving there, it digs a hole, crawls in, and waits about ten months till the next flowering.
But what happened to that mother moth? After flying to one flower, taking pollen to another, laying eggs and pollinating the pistil, the little moth dies. After leaving the ground it never once eats, but only does its work of providing for the future of its babies and the yucca plant.
There is still more: Each species of Yucca plant has its own special moth! The flower is so constructed that it can only be pollinated by one particular type of moth.
During certain years, the flowers do not appear on the plants. If the moths came out at that time, they would die, and the Yuccas would die later on. But, instead, the moths only come out when the flowers appear, even if the moths have to wait till the second or third year to come out of the ground!
"Could blind chance have achieved such perfection [referring to the Yucca plant and the pronubia moth]?." 'Ernsi Mayr, "Accident or Design: the Paradox of Evolution, " in The Evolution of Living Things (1962), p. 3.
"It is a considerable strain on one's credulity to assume that the famous yucca moth case could result from random mutations." 'Ernst Mayr, Systematics and the Origin of Species (1942), P. 296.
THORNY ACACIA The thorny acacia tree of central Africa can tell when animals are feeding too heavily on it. When that happens, it begins producing a chemical called tannin k. The tannin combines with other chemicals in the leaves, producing a bad taste. Scientists found that the tannin level is normally quite low, but within 15 minutes after leaf damage, tannin levels in the leaves nearly doubled. In addition, they discovered that when this happens, the tree gives off an odor, warning other nearby acacia trees to be on guard. In response, they immediately begin producing more tannin in their leaves also!
LADYSLIPPER The Lady's Slipper Orchid has two stamens. The lip is shaped like a smooth slipper with in-rolled edges, so the insect cannot get out by the way it entered. So it must move toward the back, or point of attachment to the stem, where there are two small exits. Heading that way, the creature must first pass beneath a stigma which takes pollen from the insect. Then it must brush past one or the other of the two stamens which sprinkle more on it. Leaving the flower, the insect never goes to another flower on the same plant, because only one flower will be open at any given time. In this way self-pollination does not occur.
RICE Rice is a land plant and must have oxygen in its root to survive. Yet it must be submerged in water. often 15 feet [46 dm] deep, in order to grow and seed. The rice must grow and keep above the water! In flood-prone areas, rice grows as much as a foot a day in order to keep its topmost leaves above the surface of the flooded rice paddy. The rice plant draws in water through its exposed leaves, as well as through a sheath of air surrounding its submerged stalk.
Rice gives off one carbon dioxide molecule for every oxygen molecule it takes in. But, because the carbon dioxide dissolves more quickly in water than does oxygen, a vacuum is created within the plant which pulls in yet more air! You could not draw air through a hose to a depth of 15 feet (46 dm], but the rice plant can draw air down its stalk that far, because of that partial vacuum.
PLANT ODDITIES The yellow evening primrose opens only at dusk, and so swiftly that it can be seen and heard. The buds sound like popping soap bubbles as they burst.
Seeds of the African baobab tree sprout more easily if they are first eaten by a baboon and passed through his digestive tract. Its digestive juices erode the tough seed coat, permitting water to penetrate more readily.
In a single growing season, 10 small water hyacinths can increase to more than 600,000 plants, and form a mat of thick vegetation an acre in size and weighing 180 tons [163 mt]!
The stems of the blue-eyed grass, a type of wild iris, are not strong enough to support more than one blossom at a time. So one flower blooms each morning, and then dies that night so that another can bloom the next day.
Bamboo can grow three feet [9 dm] in 24 hours.
The ocean contains eighty-five percent of all the plant life in the world.
A typical plant or tree receives about 10 percent of its nutrition from the ground; the rest comes from the atmosphere and sunlight.
The giant water lily, victoria regia, has leaves so large that a small child could sit on it without its sinking. The leaves are eight feet across.
Lichens have been found on bare rocks in Antarctica as close as 264 miles [424.85 km] to the South Pole. No other plant or animal life lives that near to the South Pole.
The dwarf mistletoe in America builds up hydraulic pressure within it, equal to that found in a truck tire! It does this in order to use that water pressure to catapult its seeds out to a distance of almost 50 feet [152 dm] at a speed of close to 60 miles (96.5 km] per hour. The dwarf mistletoe is a water cannon!
Tiny discs of chlorophyll move about within plant cells and adjust for different light and heat conditions. When the sunlight is too strong, the little discs turn edgewise! On an overcast day, they lie as parallel to the sky as they can in order to take in the most light.
Some plants die as soon as they have flowered, while some trees live up to 4,000 years. There is a bamboo plant in the mountains of Jamaica which takes 32 years to mature, and then flowers once and dies.
Puffball and mushroom spores have been found in large amounts 35,000 feet [10,668 m] in the air.
The Mediterranean squirting cucumber uses water pressure to shoot its seeds 40 feet (122 dm] away.
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GALL When the gallfly lays its eggs in the leaf or stem of a plant, a large ball-like growth occurs. This gall, as the growth is called, serves as a home for, and gives food to, the developing insect. Galls are of great variety, both in shape and color. Several different types of insects produce galls in plants as "nests" for their young.
Until recent decades it was thought that the gall was produced by the plant as a means of protecting itself from injury. But it is now known that the gall was produced because the insect injected a plant growth hormone into the leaf or stem! This is incredible; an insect manufacturing plant hormones in its body! Once injected, the hormone causes the growth to occur. How could an insect invent plant hormones?
THE COLOR OF PLANTS Light from the sun contains all the colors of the rainbow. When it strikes the plant, the plant absorbs the red and purple rays and uses them in photosynthesis. "Photosynthesis" is that marvelous action by which a chunk of sunlight and a chunk of water are transformed into carbohydrates (simple and complex sugars).
Because the plant absorbed the red and purple rays, the yellow and green ones are reflected back outward. This gives the landscape its great beauty.
It could have been the other way around, and the plant could have absorbed the yellow and green, and reflected the red and purple! Instead of the restful colors, we could have been surrounded with violent ones. If red, yellow, and green had been absorbed, we would see deep blue and violet in the plants. This would have been too depressing. If green, blue, and violet had been absorbed, we would only see brilliant reds and oranges all about us. This would have been too exciting and over-stimulating to the nerves. Instead we have soothing green as the predominate color of vegetation.
MADRONE AND MANZANITA In California, the madrones and manzanitas have thick, heavy leaves that can endure the cold winters. In wintertime they are broad-leaved evergreens. But in mid-summer, when their leaves are in the greatest danger of drought, they shed their leaves. When the stem leaf breaks off and the leaf falls, at the base of the petiole is to be found a corky layer. This seals off the plant, so that, even though the leaf is gone, no fluids will evaporate out through that opening. This serves as a plug to stop the passage of water from the stem. Otherwise these large bushes would dry out and die.
AIR PLANTS Some plants grow on trees and not in the soil. But they are not parasites, for their nourishment is not obtained from the tree, but from the air! Air plants, such as tropical orchids, have a mass of tissue around the roots which absorbs water from the air.
EELGRASS Eelgrass grows submerged in the shallow water of bays and estuaries near the seacoast. It is like regular grass, but much longer. Eelgrass is the only flowering plant that blooms underwater! Its pollen is shed into the water, and is carried by currents to other nearby plants.
POLLINATION Night-blooming flowers are white or yellow, so they will be visible in the darkness. To make sure they will be found by pollinating insects, they are also provided with fragrant odors. Many of them are closed and odorless during the daytime.
Wind-pollinated flowers do not have brightly colored corollas. They do not need them, since they do not need to attract insects to pollinate them.
The brilliant flowers are generally pollinated by insects. These flowers are also equipped with odors emitted into the air during the day in order to attract insect visitors.
Sometimes the petals have guidelines (stripes) to help insects land and enter the flower at just the right place. In order to get into the nectar pots, the insect first passes by the anthers and stigma, which are always in front of the nectar pots.
AUSTRALIAN PLANT ROOTS In the Australian back country (the "bush") the natives search for a certain small plant which, although it only has about 4 inches [10.16 cm] of leaves above the soil, has roots which are larger than footballs and full of water. These roots are reservoirs to be drawn upon during the almost continuous dry weather in those regions. Finding these, the aborigines split them open and drink the water.
There is another desert plant in the Australian "out-back" which has roots which are shaped like long strings of sausages, 10 to 18 feet [30-55 dm] in length. Finding them, the natives will hang them on trees so that the water will run out.
MALLOW As do many other plants, the leaves of the mallow weed follow the movement of the sun across the sky. Then, as soon as the sun sets, all the mallow plants turn and face east to where it will rise in the morning.
DUVANA The Duvana dependens grows a special gall, an enlargement, on its stem which is of no use to the plant itself. But the moth Cecidosis eremita needs that gall in order to survive. It comes to the Duvana and lays its eggs in that gall.
KELP The California Kelp is to be found a half-mile off the coast of California. It grows in giant kelp forests which are 25 feet [76 dm] tall. Millions of baby fish and crabs grow up in the tangled leaves of these forests. Thousands of other fish and sea creatures live there also. It provides food, shelter, and nesting places for millions.
In addition, bald eagles swoop down and obtain their food from creatures at the top of this forest, and harbor seals get their food from it also. But most of the creatures in the kelp forest are not caught and they grow up and replenish the marine ecological system.
All the creatures eating the kelp leaves are no problem; it simply grows more leaves. Yet the spiny sea urchin is different; it is a menace, for it cuts through the kelp stem. But the sea otter is in the kelp forest also, and it thoroughly enjoys eating sea urchins.
Thus the balance continues. Only man can upset it by over harvesting the kelp or killing the sea otters.
COAST REDWOOD This tree on the Northern California coast sprouts from one of the smallest of seeds, yet grows taller than a 35-story building or the Statue of Liberty. It easily reaches 350 feet [107 m] in height, and the tallest one is 375 feet [114 m]. Twenty feet across and 65 feet around, its roots only go down 3 or 4 feet [91-122 cm] , but they spread out 80 feet [244 dm] on each side. The first branch is over 150 feet [457 dm] up, and its bark is over a foot thick. It more than a thousand years old (while the giant Sequoia in the Sierra Nevada Mountains is 4,000 years old).
These 350-foot [114 m] high giants along the Northern California coast rain down their tiny seeds, but most of them are eaten. Only 10 percent of the redwood in the forests came from seeds; 90 percent came from sprouts.
At the base of each tree, and surrounding it in a circular collar, are wartlike growths from its roots. These are called "redwood burls." If a tree gets into serious trouble from fire, bugs, etc. , it will send a hormone message to the burls and immediately they will sprout! As many as 100 will sprout up around the parent tree. In 20 years, each sprout will be 50 feet [152 dm] tall and 8 feet [24 dm] in diameter.
The coast redwood grows in only one place in the world: the northern California coast. This is partly due to the moderate climate, but another reason is the fog that comes in nearly every day during the hot and dry part of the year and drips down, moistening trees, ground, and roots. Without that fog the coast redwood could not live.
SORREL On the ground beneath the tall coast redwood is the tiny sorrel. This is a three-leaved plant which is designed to grow in the continuous shadow of the giant trees, above which the sky is frequently overcast with fog. The small leaves of the sorrel lie flat catching every bit of skylight they can.
But occasionally the sunlight shines through a patch in the tree tops and hits those leaves. Immediately, the little plant must do something or it will die. This is because it is designed for shadowed living, not sunlit living! Within a short time, the sunlight will wither the plant and it will perish.
Quickly, the little plant folds its three leaves upright--like shutting an umbrella. This shuts out the sunlight and heat. Only exposed now is the bottom side, which on most plants also has chlorophyll, but on the sorrel has a purple screen to protect the plant.
As an added protection, sorrel primarily grows by sending out runners. In this way, many plants are connected underground. They all cooperate with one another in an emergency and if one gets into a patch of sunlight, it sends out a message to the others and they send more moisture to it.
ANCHOMANES Plants of the Anchomanes genus only have one leaf, produce heat like warm-blooded animals, and make insect food. Anchomanes only grow in Africa. Above the root, there is only one leaf, but it is about 20 feet [61 dm] tall and 6 feet [183 cm] wide! When it blooms, it generates heat by burning carbohydrates. The flower only opens at night, has no scent, and is a dark maroon color. Yet somehow it is located by a certain pollinating beetle. Arriving at the flower, the beetles feed on small granular lumps on the underside of the flower, made especially for them. Soon large numbers of beetles have arrived, and they mate and lay their eggs on the flower, where the young develop without damaging the plant.
DUTCHMAN'S PIPE The Dutchman's Pipe has a tubular leaf that wraps around its flower. This leaf is coated with wax. Certain insects are attracted by the strong odor of the flower and land on the leaf. As soon as an insect does, it slides down its slippery sides into a chamber at the bottom. There, the ripe stigmas receive the pollen that the insect brought with it, and pollination takes place.
Three days then pass by with the insect trapped by hairs near the bottom and the wax farther up the sides. After that, the flower's own pollen ripens and dusts the insect. As soon as that happens, the imprisoning hairs wilt and the waxed slide of the funnel-like flower bends over until it is nearly level. The insect now walks out with his supply of pollen and flies off to do it again. One might think that the insect could starve living like that, but all the while it is inside the flower it is feeding on a feast of stored nectar.
CORNSILK TUBES Cornsllk is that golden hair which protrudes out of an ear of corn. When a single bit of corn pollen lands on the pink silk at the top of the ear, it stays there because the silk thread is sticky. That extremely tiny pollen grain then begins making a tube that eats its way into the thread. If the grain lands near the outer end of the silk, this tube may lengthen by ten inches as it travels down the inside of the thread of "silk." It is striving to reach an egg cell far below at the base of the thread. Arriving there, it will slowly transform it into a kernel of corn.
LONG-LIVED POLLEN Each grain of plant pollen is enclosed in a case that is almost indestructible. It does not decay as do the other parts of the plant. Pollen grains thrown out by plants have survived for long periods of time. Even after they finally die, the outer hull continues to retain its same shape. This is why pollen can be found wherever man searches for fossils. Pollen grains have been found in the lowest strata, the Cambrian of Grand Canyon, showing that plants were living and thriving way back in the beginning. And would we expect otherwise? Without plants in the beginning, none of us would be alive today!
VARIEGATED POLLEN There are over half a million flowering plants in the world, plus large numbers of trees, bushes and other plants. Yet every species of plant in the world that produces pollen, makes a uniquely shaped pollen grain! No two plant types form the shape of their pollen in exactly the same way.
Under a microscope, a grain of pollen looks like an exquisite jewel. The grains may look like disks, footballs, canoes, dumbbells, crystals, etc., but no two will be exactly alike unless they come from the same species.
OPHRYS ORCHIDS Certain varieties of the Ophrys orchid have on their petals what appears to be a three-dimensional picture of a female wasp, complete with eyes, antennae and wings. The petal even gives off the odor of a female in mating condition! When the male arrives to mate, he only pollinates the flower.
MILKWEED The milkweed produces glycosides which provide no nourishment to the plant, but instead protect the monarch butterfly which feeds upon the plant. Without that protection, the Monarch could not survive, for it only eats from the milkweed during its lifetime.
Certain plants, including the milkweed, produce a sticky fluid which protect them against aphids. When aphids come to dine, they suck out some of this fluid and it causes a sticky, coagulated mess in their tubes and stomach. The aphids either depart immediately or die.
RABBIT AND AMANITA The Amanita is one of the deadliest things in the world. Mushroom experts declare that the Amanita is the only mushroom in the world which will kill a person. Unfortunately, it comes in many different colors. (In America it is most commonly seen in the "death angel," a pure white variety; if you see any growing on your lawn or in the woods, warn your children to leave them alone!) If no antidote is given within 30 minutes, death will follow.
But the rabbit can eat the Amanita without experiencing any ill effects. The poison in this mushroom (phallin) causes it no harm. No one knows why the rabbit is unaffected by one of most powerful poisons known to mankind.
MOVING THE POLLEN AROUND In most instances, a plant places the fresh new supply of pollen on exactly the place on the insect where, but a moment before, it removed the pollen from the previous plant. Yet there are exceptions. Sometimes the pollen is collected by the plant in a different location on the insect's body than it was deposited by the previous flower. So what does the insect do? In such cases a certain type of insect will pollinate that particular species of flowerand before entering the second flower, it will obligingly shift its load to the proper flower pick-up point!
SCORPIURUS The pod of the Scorpiurus, resembles a nice, tasty centipede. Sighting it, birds grab it and fly off with it. Gripping it in their teeth, the pod breaks open and scatters seeds as they go. Landing, they find that it is not edible and spit out the now-empty pod.
BUCKET ORCHID This orchid has a slightly fermented nectar which makes the bee wobbly on its feet, causing it to slip into a bucket of liquid. The only exit is along a route that causes it to wriggle under a rod that dusts the bee with pollen.
ANT AND ACACIA TREE Acacia trees have beautiful flowers in the spring. If you were to look closely you would find the Pseudomyrma ant in them. It lives in the Acacia tree and feeds on special fruit on the leaves. This fruit does not contain any seeds, and has nothing to do with producing more Acacia trees. It is only there to provide food for the Pseudomyrma ant.
But, because that fruit is there, the little ant is there. In turn, the ant travels about over the tree and chases off, or eats, other insects which would eat the Acacia leaves. They even destroy climbing vines which would kill the tree, as well as small nearby trees which could grow and shade their special tree. Each tree has its own resident colony of ants which feed on and protect it. This acacia is the only plant in the world that produces the animal starch, glycogen.
One type of acacia has swollen thorns in which the ants hollow out nests. When an ant queen discovers an unoccupied tree, she burrows into a green thorn and lays her eggs. The larvae are fed with carbohydrates from the leaf tips. Eventually the colony of ants on one tree may number 30,000, when all the thorns are occupied. Then the colony splits into two, and part of it swarms to another tree.
CAMBIUM LAYER A marvelous outer circle of cells is on every tree. It is called the cambium. This is the growing edge of the tree. On the inside, it makes xylem tubes thus increasing the amount of wood in the tree. On the outside of the cambium layer, it makes phloem tubes which adds on more outer stem or bark. No scientist can explain where the cambium came from. But without it, there would be no plants
LEAVES What are leaves? Each one is a power station. The leaf includes chloroplasts, guard cells, special chemicals, and much, much more. Filled with tubing through which fluids flow, it has five layers of water-proof coatings, and the top coat is akin to varnish.
The location of each leaf dovetails into the others, so that each leaf can obtain as much sunlight as possible. In order to do that, each leaf must be moved into the best position relative to the others. Where are the brains to do this? in the leaf? In the branch?
Each leaf is a sunlight machine. It takes in sunlight and, together with minerals and water from the roots, the plant turns out all the basic food used by every plant and animal in the entire world! Without the leaf, we would all quickly perish.
Man makes solar panels to catch the sunlight. These are spread out so each plate will receive sunlight. Imagine how much space the leaves of a tree would need, if they were spread out flat all over the ground? God's way is much more efficient. All the life on our planet is fueled by solar power!
CHLOROPLASTS Scientists estimate that over 400 million-million horsepower of solar energy reaches the earth every day. Photosynthesis is the process by which sunlight is transformed into carbohydrates. This takes place in the chloroplasts. Each one is lens-shaped, something like an almost flat cone with the rounded part on the upper side. Sunlight enters from above.
Inside the chloroplast are tiny cylinders that look something like the small circular batteries used in hearing aids and small electrical devices. These are called lamellae, and is actually a stack of several disk-shaped thylakoids. Each thylakoid is the shape of a coin. Several of these are stacked on top of each other, and this makes a single lamelium. A small narrow band connects each stack to another stack. They look like they are all wired like a bunch of batteries.
Sunlight is processed by chlorophyll in those stacks, and then stored there as chemical energy in the form of sugar molecules. Chlorophyll, itself, is very complicated and never exists outside of the plant, just as DNA and ten thousands of other chemical structures never exist outside plants and/or animals. If they are not found outside, how did they ever get inside?
BLUE-GREEN ALGAE This IS probably the simplest of the plants. Yet its structure, functions, and chemistry is awesome, and all of it had to be present and functioning from the very beginning.
Blue-green algae produce more oxygen than almost anything else in the world. They are found in oceans, waterways, and lakes. They photosynthesize and respire almost like higher plants. Some of them can fix nitrogen from the air, so that their food requirements are minimal. These algae serve, under the name plankton, as the basic food for animal life in fresh and salt water throughout the entire world.
MITOCHONDRION AND ATP Mitochondria within the plant cell are little capsule-shaped containers. They take in sugars, fats and even proteins, which are made elsewhere in the plant, and change these substances into ATP.
Each molecule of ATP is a miniature storage battery and contains electrical power. ATP molecules are stored in the plant and used whenever needed for a variety of purposes, whenever energy is needed. ATP is an amazing substance.
PLANT BLOOD A drop of blood contains about a hundred million red cells. Each of these small doughnut-shaped discs is covered with one of the largest and most complex molecules in nature: hemoglobin. Hemoglobin has been called a "molecular lung," for it is an oxygen processor just as is the lung. Remove the iron from the center of hemoglobin and place magnesium in its place,and you have chlorophyll, which is so important to the life of the plant.
Are people related to peas? A nitrogen-fixing bacterium, Rhizobium, in the root nodules of peas, enables the legumes to make hemoglobin genes. Rhizobium has hemoglobin genes also. What is hemoglobin doing in peas and bacteria!
But that need not surprise you. The water flea, Daphnia, has hemoglobin also! Then consider the ice-fish, which lives in Antarctic waters averaging 2C [35.6F). It has no hemoglobin, but instead has a form of antifreeze which circulates through its veins!
RYE PLANTS A single plant of winter rye has roots one hundred times greater than all the parts growing above ground. Its regular brown roots grow three miles of new roots per day. In addition, billions of microscopic white root hairs branch out from them, sliding through spaces between grains of soil. Adding these to the already large total, scientists decided that rye adds 53 miles [85 km) of additional roots per day.
SEEDS UNLIMITED Plants pour out seeds. A single plant of red clover only a few inches tall turns out 500 copies of itself. The weedy crabgrass makes 90,000 seeds on each plant. Pigweed produces a million seeds per plant.
One orchid was estimated to grow 3,770,000 seeds on a single plant. Orchids grow high up in jungle trees, and their seed must find a limb which is wet and the bark slightly decayed. So millions of seeds, as fine as the finest powder float off into the air.
Dandelion seeds come equipped with parachutes. Maple seeds have wings and flutter off like butterflies. Some water plants produce seeds with air-filled floats. When released, they just sail away, as the wind blows them along.
Other plants have pods that snap open and shoot their seeds out as from guns. Witch hazel pods gradually press tighter and tighter against their slippery seeds, until out they pop and travel some distance before landing. As the squirting cucumber grows, its pod thickens inwardly. The fluid center comes under ever-increased pressure till--bang! and the pressure becomes so great that the seeds shoot out like a cork from a bottle.
A small number of dry bean seeds, accidentally left under a concrete sidewalk, will, when they get wet, swell with such power that they will break the concrete.
Some desert seeds just lie on the ground and refuse to sprout--till a desert rain of a half inch or more occurs. Only a heavy rain will provide them with enough moisture to go through their brief cycle of life. Then they go to work fast!
Scientists tried to figure out a problem here: Why is it these seeds will not sprout if they are only wet from below? Why must they also be soaked from above! The reason is this: The desert soil has too many salts in it--salts that will prevent the seeds from sprouting. So a rain is needed to wash down the salts so that the seeds can sprout and grow.
KNOBCONE PINE SEEDS The knobcone pine has fire insurance. Unlike most pine trees, which open their cones and let the seeds slide out when ripe, the knobcone holds its ripe seeds sealed inside the cone. This cone is almost as hard as rock and will remain on the tree for as long as 50 years. These cones hug the trunk of the tree, so they are eventually swallowed by bark growing around them. But inside those cones, the seeds are still alive. Even if the tree dies, the waiting seeds continue to be alive. Still more time passes, and then a forest fire occurs.
Since only a fire can release those seeds, they now spring into action! As the fire passes over the tree, the cones explode like popcorn. This explosion flings seeds everywhere, and they take root in the ashes after they have been cooled and wet by rain. In this way, these young trees grow and protect the forest floor from erosion. Later, other trees reforest the area along with them.
TRAVELING SEEDS Some seeds are inside fruit, and when eaten the seeds reach the ground and sprout. Acorns are carried off by squirrels who know enough to bury them, and then forget where many of them are so they can sprout.
The burdock seed has big hooks that hitchhike on passing animals and people. Seeds of burr, marigold, ticktrefoil, or Spanish needles, travel in the same way.
Other seeds rely not on hooks but sticky surfaces. Still others are coated with oil, so ants carry them off to their underground homes where some of them will sprout.
Then there are the seeds which are part of such contraptions as slingshots, catapults, spring mechanisms, exploding parts, and cannons.
What about the overcoat seed on the wild oat? It has an overcoat called an awn which looks like a partly-bent leg of a grasshopper. On warm, dry days, the leg suddenly straightens with such force that the seed is lifted over rough ground and partially burrows itself into the ground.
SMALLEST TO THE LARGEST One of the very smallest of the seeds, eventually grows into the biggest living thing on earth (and probably the heaviest too). The giant sequoia of the Sierra Nevada range grows over 300 feet [91 m] high, with a diameter which may be 36 feet [11 m]. One tree may contain enough wood to build 50 six-room houses. The bark is two feet [61 cm] thick, and its roots cover 3 or 4 acres [1.2-1.6 ha].
Yet its seeds are little more than a pinhead surrounded by tiny wings.
ROOTS Green leaves feed the world, but they cannot function without the roots. Each tiny rootlet has a small cap protecting its end as it grows outward. Each tiny cap is lubricated with oil. Continually these rootlets, covered by caps, are pushing through the soil.
Behind them, root hairs absorb water and minerals, which travel up extremely small channels in the sapwood. This fluid moves upward at 200 feet [610 dm] per hour! Up and up it goes, till it reaches the factories in the leaves. Here sugars and amino acids are made, which are then sent throughout the tree to nourish it.
Large amounts of excess water evaporates from the leaves into the atmosphere, which rise upward and form clouds to later fall as rain and help plants, animals, and man.
ULTRA-VIOLET PLANTS Certain flowers, such as Jasminium primulinum, have been found to have hidden patterns, generally on the rear of the flowers, which can be seen only under ultraviolet light. After careful investigation, scientists have decided that certain insects find these flowers by ultra-violet light!
It is known that some insects (how many has not yet been determined) can see ultra-violet light, at least the near ultra-violet spectrum. For example, bees can see UV light. No one has so far been able to figure out how they do it.
TREE PUMP On a warm summer day, a large tree may pump over a thousand gallons [3785 I] of water from the ground, up through its trunk and branches, and out into its leaves. That is four tons [3.6 mt] of water in one day! Drop by drop, the water is drawn out of the soil by the roots. But it is what is happening in the top of the tree 30 to 100 feet [91-305 dm] up in the air, that causes the water to be taken on up. As water evaporates from the leaves, it produces a negative pressure inside the tree's tubing If you were to cut one of those vessels, a hissing sound, of air rushing in, could be heard. Negative pressures as low as negative 20 atmospheres have been found high in trees. This is what draws the water up the tree.
REPELLING AN INSECT THROUGH ITS STOMACH Certain plants, including the tomato and potato, have special ways of defending themselves against insects. If a leaf is damaged as an insect begins to eat it, the plant produces a considerable concentration of a substance which causes problems in the insect's stomach so it cannot digest its food. The substance causes the insect's stomach digestive juices--proteinases--to stop flowing! Henceforth, the insect leaves that plant alone.
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TITYRA AND CASEARIA In the forests Of Costa Rica, there is a bird and a tree that work together for mutual benefit. Most birds eat fruit wherever they might find it, dropping the seeds at the base of the tree where most of them die. But the tityra bird consistently depends on the Casearia corymbosa tree for food. In turn, that tree depends on the tityira to scatter its seeds so more Casearia trees will grow.
Two species of tityra birds pluck Casearia fruit, but immediately fly off with the fruit some distance from the parent tree, dropping the seed where it has a much better chance of successful germination and growth.
H.F. Howe, the plant researcher who discovered this relationship, commented that it is clear that without either the bird or the tree, the other would perish.
FIRE SEED Many trees depend on forest fires to propagate them. They lay there for years until a fire passes through, and then, afterward, they sprout. The lodgepole pine, on the West Coast, has special fire insurance. It produces two types of cones. The first cone opens and releases its seeds at the regular time in the spring. But the second remains unopened, falls to the ground and lies dormant for years. When a forest fire occurs, it shocks those sealed cones into opening. The seeds fall out and a new forest begins growing.
BULL'S HORN ACACIA AND THE ANTS The myrmecophytes are plants in South America which are inhabited by ants. A species of ferocious stinging ants come to these trees and make their home there. They pierce the thorns to use as nests, and eat small green bumps on the twigs and little brown nubbins on the leaf tips. Thus these ants get both food and shelter from these trees.
In return, they protect that tree from encroaching insects, goats, and other foraging creatures of various sizes. In addition, the ants make regular forays in all directions from their tree and destroy strangler vines which would kill it, and nip off every green shoot that might threaten to encroach upon the space reserved for their tree to grow and thrive.
To see what would happen to the tree if it lost its ants, scientists carefully killed all the ants on several of these trees, and then made sure that no more ants arrived. Within 2 to 15 months the trees died, either eaten by foraging animals and insects or suffocated by the vegetation of the surrounding jungle.
MANGROVE'S SALT-FREE DIET The mangrove tree is one of the few trees that grows in salt water. Its roots suck up the seawater, yet the salt in that water would kill the tree within hours if taken up through the roots and sent up the trunk into the leaves. To solve this problem, the roots carefully filter out the salt by passing it through special membranes that remove it.
One species of mangrove does it differently: Partly-filtered sea water is sent up to the leaves, where it passes through small glands on the underside of leaves, where excess salt is taken out and dropped through tiny holes in the bottom of the leaf.
CAP-THROWING FUNGUS The cap-throwing fungus has a built-in clock mechanism that is keyed to the movements of the sun. Throughout the day it turns with the sun. Then, the next morning at about 9 a.m., it knows that the best time has come to throw out its spores. In response to its light-sensing system, the cap-throwing fungus explodes its top, and hurls out its spores. Upon landing, they are picked up by passing animals and carried elsewhere. A glue coating on the spores aids in this process.
PLANT BLADDERWORT The common bladderwort (Utricularia vulgarls) lives in ponds. It is shaped like a funnel and spends its time snaring small aquatic insects and crustacea. Its mouth has a hinged trapdoor with a very sensitive trigger. To set the trap, the sac of the funnel is collapsed by pushing all the water out of it.
Along the outer edge of the funnel top are trigger hairs and also a hinged trapdoor. When a swimming insect or plankton touches the hair trigger, the bladder, the inside of the funnel or body of the bladderwort expands in 1/50th of a second! This produces a strong vacuum which sucks the insect into the funnel. The vacuum pressure thrusts the entire bladderwort forward a distance.
THE FIBONACCI SERIES Plants and many other things in nature are keyed to various involved mathematical formulas, one of which is the Fibonacci series. Leonardo of Pisa, nicknamed Fibonacci (c. 1170-1230 A. D.) discovered this particular formula.
It begins with: 0,1,1,2,3,5,8,13,21,... and runs onward, with each number the sum of the previous two numbers (8 + 13 = 21, 13 + 21 = 34, etc.). This series is to be found in the reproduction of male bees, the number of spiral floret formations visible in many sunflowers, spiraled scales on pine cones and pineapples, the arrangement of leaves on twigs, as well as many other structures. If you were to look . downward from above on a tree trunk, you would find that the branches emerge in accordance with the Fibonacci pattern. One will issue from the trunk at a certain point, the next one above it will emerge on a different side of the tree at a point in relation to the series. Gaze into a sunflower head and you will clearly see the Fibonacci series in the manner in which the seeds are arranged; there you see lines spiraling outward. Look sideways at a closed pine cone and you will see the series spiraling around the cone.
MONARCH AND MILKWEED The milkweed plant produces a latex that is sticky and poisonous. Most birds, insects, and animals avoid it. But the monarch butterfly feeds exclusively on it. Females lay their eggs on the milkweed, and their larvae feed on the leaves. As they do so, they pack away the deadly, active ingredient into special sealed-off body cells. While the poison does the caterpillar no harm, it makes the insect distasteful to predators. If an inexperienced blue jay eats a monarch, it immediately vomits it up, and will never again go near that butterfly.
MONARCH AND VICEROY The viceroy butterfly looks strikingly like the monarch, but it lacks two special qualities which the monarch has: (1) The monarch has the milkweed latex in its body to protect it against enemies. But the viceroy looks so much like the monarch that predators leave it alone also, thinking it is a monarch. (2) The monarch migrates in the fall to the far south, wintering over in southern California and Mexico. The viceroy dies in the fall.
MAINTAINING BODY HEAT It is Well known that one of the special qualities of mammals is that they maintain an even body temperature. But certain plants do the same. The Philodendron selloum at certain times maintains a core temperature of 38 to 46C (100.4-114.8F], despite air temperatures all the way from 4 to 39C [39.2 102.2F]. Small male flowers are responsible for equalizing plant temperature. It is thought that the heat helps the plant diffuse scent and attract insects. Perhaps there are other reasons.
There is evidence that some insects have organs which can detect infrared (heat) radiation. At any rate, plant temperature may be one of the factors attracting them to its flowers.
TREE MECHANICS Auxins are plant hormones which determine growth, where it will occur on the plant and to what extent. Wherever the auxins flow to, that is where the growth will occur.
In the spring, growth begins in the twigs and progresses down the stem or trunk. Differences in auxin concentrations cause trees to grow toward the light, and help the end of a tree that has been bent over to grow upward.
One scientist, T.A. McMahon, worked out the formula for the general size and height of trees. The mathematical formula goes something like this: "The diameter of trees will vary with height raised to the 3/2 power; that is the length times the square root of the length." This is a lot of complicated mathematics for a tree to keep track of, yet somehow it does it. Here is a little more of this formula: "The mean height trees obtain is only about 25 percent of that which they could obtain and still not buckle. In other words, in regard to buckling, trees are designed with a safety factor of about four."
Another scientist analyzed the knees of cypress trees, and decided that they provide exactly the type of mechanical support an engineer would provide for a tree growing in a swamp.
PREPARING FOR WINTER Plants know that winter is coming because the weather keeps getting colder. In addition, many, if not most, also
measure the length of the day. Many flower plants measure the length of the dark period in every 24 hour day. By this they can know that winter is nearing. Many seeds depend on winter to crack their seed coats enough to soak up water for sprouting in the spring. Many tree buds will not open up until after a certain amount of cold weather. Apple buds need 1,000 to 1,400 hours of near-freezing temperature before they will open in the spring.
DIATOMS The humble diatom is probability one of the simplest plants in existence. Simple?
It is extremely tiny and mostly made of fragile glass with many little openings, yet it is almost indestructible. It is fireproof, yet makes dynamite. It has explosive properties, yet is used in mines to reduce explosions. It tastes like fish oil, yet is used in toothpaste. It has no apparent means of locomotion, yet it travels around by straining its own cytoplasm through one window and out the other. It looks something like an exquisitely carved pillbox, yet this pillbox duplicates itself by growing a new lid on the box, and then the lid grows a new box.
There are over 5,000 different types of diatoms. All are tiny glass houses; all are intricately marked with design work, yet no two varieties look exactly alike. It is something like an algae, yet decidedly different. Each diatom can comfortably live in a thimble-full of water with 14 million other diatoms.
It moves in the water with the agility of an animal, yet it is a plant which manufactures chlorophyll and produces oxygen and food. But it does not produce carbohydrates, as do other plants. Instead, it produces the oil that give fish a "fishy" smell. Yet its skeleton is used to refine sugar!
Although one of the smallest of the one-celled organisms, the diatom recycles 90 percent of the oxygen we breath, and also provides most of the food for fish and whales. This "simpler form of life" is so complex in construction that it is used to test the resolving power of microscope lenses.
ROSE OF SHARON This little plant grows in the dry deserts of Palestine and is not actually a rose but a member of the mustard family.
Its scientific name, Anastatica, means "resurrection plant," because when the dried up skeleton of the plant, nothing more than a dried-up ball of twigs, is immersed in water, it opens up and extends its branches like a miniature tree.
It begins to bloom in March and April, and by May its seeds are ripe, but they do not open. They remain dormant, tightly enclosed within little pods or balls. By that time the leaves have fallen off and the dry, hard, twigs of the plant have shrunken together and resemble a closed fist.
But that apparently dead plant is all the while continually measuring rainfall. When some comes, little by little it releases a few of its seeds. Here is how this complicated action takes place,and all done by a plant that appears to be dead:
The seeds are enclosed in a ball. The first part of a rain causes some of the upper balls to open. If more rain falls right away, some of the peripheral seeds will drop out. If more rain falls rather quickly, some more balls will open and drop part of their seeds. Seeds farther into the center of the cluster of twigs may wait for decades or even centuries to open.
The twiggy mass is so tightly held together that it requires rain to expand it. When that happens, then additional rain can fall on the seed balls and permit them to open and a few seeds to fall. Additional rain and more seeds will drop out. At any point if the rain stops, then the twiggy mass will close up again.
It requires 4 millimeters [.157 in] of rain to open the twig mass, which gradually opens in about 2 hours. When the seeds fall to the ground, they germinate rapidlyin 8 hoursbefore the earth dries out.
This plant is only found in the driest part of Palestine. In those areas where there is more rainfall, none are found. This is due to the fact that a small gerbil lives in the wetter areasand relishes Rose of Sharon seeds.
In nature, everything is in perfect balance.
WALKING "SEEDS" AND "TWIGS" The male flowers in oak trees are called catkins. Sometimes the catkins start walking away! What happens is that a certain caterpillar feeds on catkins until it is so full of them, that it begins looking like them! In this way, it avoids being eaten by birds who are looking for juicy caterpillars, not catkins.
The caterpillars which eat these catkins in the spring, end up looking like them. even to having fake pollen sacks! But those caterpillars of that same species, which hatch out in the fall, also feed in the oak trees, and end up looking like oak twigs! In both cases it is the same type of caterpillar; the only difference is their diet.
DIFFICULT LIVING Some flowers push their way up through snow and ice, while others lie dormant in the hot sands of the desert for years, and then spring forth and bloom after a rain that may come only once in a decade.
Some bacteria can live in hot springs at a temperature of 175F [79.4C], while spores of other bacteria have survived after being exposed to the temperature of liquid air (-310F [-190C]).
UNUSUAL PLANTS Bamboo grows all over the world, yet every so often it dies. No one knows why. When it dies, all the bamboo plants throughout the world also die, even though separated by thousands of miles! Then, all over the planet, new sprouts shoot up and this fast growing plant is seemingly resurrected.
There are several kinds of "air plants" (epiphytes) that get their nourishment from the oxygen, water, and minerals they find in the air around them. The staghorn fern is an example. It grows on other trees, with its leaves pressed against the trunk of the tree to conserve moisture. Beneath the leaves are large masses of roots which extract nourishment directly from the atmosphere.
The great water lily of the Amazon and Indonesia has leaf blades that are five feet in diameter. Some palms have leaves 20 feet [61 dm] long. There are seaweeds that grow 450 feet [137 m] down in the ocean where there is almost no light.
HELICONIUS AND PASSION FLOWER Butterflies of the genus Heliconius only lay their eggs on the tropical vine, the Passiflora, which is the passion-flower plant. The vine has features which appear to mimic the distinctive bright yellow eggs of the butterfly.
Each species of this butterfly lays its eggs on only one species of passion-flower, so this makes it difficult for the female butterfly to locate the proper plant. For example, on the island of Barro Colorado in Panama, there are 1,369 plant species, but only 11 of them are passion-flower species. So the little butterfly has available to it only a few of all the plants on the island.
Lawrence E. Gilbert has carefully studied the little butterflies. Arriving at a passion-flower, the female must figure out if it is the correct species. Using a specially modified pair of front legs, it "drums" on the surface of the leaf, trying to figure out if it is the correct species. Somehow it is able to identify the plant in this way.
Next, the butterfly must ascertain whether the plant has room for more eggs. If too many are laid, the plant will later be stripped of its leaves by the butterfly's offspring--the caterpillars--and die. The death of that species of passion-flower will bring death to the type of butterflies depending on it.
So the female must next make "an egg load assessment." This is a well-documented occurrence not only in Heliconius butterflies, but other insects as well. As a result of this survey, the female may lay an egg, or may fly off to check out another passion-flower plant. Research studies reveal that very few eggs are ever laid on any one plant. In addition, as part of the "assessment," the female will check on the possibility that the plant might be too young. If the eggs are deposited too early, the hatching caterpillar may devour the shoots before its new leaves appear. The caterpillars will then only have tough old leaves to eat and will die from starvation. A lot of careful, yet complicated, thinking must be done by that tiny insect.
Certain passion-flower species have yellow markings similar in color to the Heliconius eggs. It was found in greehouse experiments that eggs were deposited on 5 percent of the plants which had the yellow markings, compared to 30 percent of those without them.
In another experiment, female butterflies were turned loose in a greenhouse with plants, some of which already had eggs on them and some of which didn't. The egg-free plants had new eggs placed on them 70 percent of the time, whereas only 30 percent of those with eggs had additional ones deposited. In addition, the butterfly took twice as long to lay eggs on that 30 percent of the plants, because it first checked out all the other plants, and finally, in desperation, laid additional eggs on plants that already had other eggs. But when this was done, the new eggs were laid on the plant as far as possible from where other eggs were already on itto insure that there would be enough food for both clutches of caterpillars when they hatched.
Pretty smart butterflies; too smart for a creature that tiny.
Similar studies of butterflies and plants in America have resulted in similar findings. This would include the swallowtail butterfly and plants of the genus Aristolochia. So there are a variety of other insects which go through the difficult decision making process about plant species, and egg assessment that the Heliconius must make.
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Chapter 12 The Plants
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