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Denis Giles

12 September 2016

Created: 12 September 2016

Last Updated: 12 September 2016

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By Maneka Sanjay Gandhi

One of the most disturbing movies I have seen was in 1975 – a virus comes through the water system of a building and turns everyone into sex crazed monsters before they die in agony.  I have still not forgotten it. An entire horror movie genre is devoted to parasites – the extremely popular vampire movies are one example.

The word parasite means, "one who eats at the table of another" Parasitism — a survival strategy that involves hijacking a host's nutrients for one's own benefit — has emerged in the animal kingdom in at least 223 species, according to a study published July 19 in the journal Biology Letters. Those inside their host are known as endoparasites, whereas those found outside their hosts are ectoparasites. The majority of parasites in the animal kingdom are invertebrates - virus, fungi, bacteria, amoebae, flagellates and sporozoa (such as the malarial parasites). Worms and flukes are very important parasites of man and mammals. 1.4 billion people have roundworms. In fact, 342 kinds of worm parasites affect all people. Endoparasites include ticks, mites, lice and fleas.

If parasitism was simply the sucking of food/blood from the host, that would be bad enough. But some parasites also capture the mind and make the host change its behaviour to benefit them – in effect creating a zombie.

The Ophiocordyceps unilateralis fungus prefers the undersides of leaves of plants growing on the forest floor as temperature, humidity and sunlight are ideal for it to grow and reproduce. The parasite invades ants and compels them to go to a low leaf, bite a vein on the underside and die hanging upside down. The fungus erupts a long stalk from the ant’s head with which it sprinkles its spores onto other ants.

The chest-bursting alien in Ridley Scott's "Alien" was inspired by parasitoid wasps. These wasps lay their eggs in caterpillars, beetles and other insects. When the eggs hatch, they crunch their way out of their living incubators. One wasp species, Dinocampus coccinellae, target ladybugs. A single egg is laid in the abdomen. The larva eats its way out and spins a cocoon underneath the ladybug who lives on as one of the undead, partially paralyzed on top of the cocoon. The wasp larva provides resources to keep the ladybug alive, while the ladybug provides protection from bugs that might otherwise eat the larva.

The female Hymenoepimecis argyraphaga wasp hunts down the Plesiometa argyra spider and paralyzes it for about 10 minutes with a sting. In that time, she lays an egg, attaches it to the spider's belly and departs. When the spider recovers it goes about its business as though nothing has happened.  All the while the wasp egg is growing. Some days later it hatches, stabs a hole in the spider's stomach and begins feeding off it. The infant wasp injects some kind of psychoactive substance that convinces the spider to spin a new kind of web designed to provide shelter from the weather and predators. When it's done, the wasp kills the spider, eats it and then uses the freshly spun web to wind itself into a cocoon. Two weeks later a fully grown wasp emerges.

Glypatapanteles wasps lay up to 80 eggs on a live caterpillar. When these hatch the larvae snack on the host’s body and then attach themselves to a nearby plant and form a cocoon. The caterpillar who is still alive, strangely, turns bodyguard. It starves itself while standing guard over the cocoons, violently swinging its head to beat away predators. How the parasites cause the caterpillars to turn into faithful guardians is unknown, but unparasitized caterpillars don’t behave like this.

Horsehair worms are parasites of crickets. The larvae live in water and are eaten by mosquitoes who are then eaten by crickets. The worms burrow into the gut and grow to adulthood.  They need to get back into the water to lay eggs. They cause the cricket to become suicidal. Normally crickets stay away from water, but infected hosts run into it and drown. The worms emerge from the dead body.

The parasitic barnacle, Sacculina carcini, invades crabs. It sprouts tendrils that reach throughout the victim's body, even coiling around its eyestalks. Living off nutrients from the crab’s blood, this parasite grows a bulge on the host’s underside where it keeps its eggs. It alters the mind of the crab so that the female crab nurtures this knob as she would her own fertilized eggs. Even the male crab grows a wide female abdomen to accommodate the barnacle's knob and protects the eggs just as a female would. Then the parasite directs its host out to deeper waters where it can avoid predators and competition for food.

Toxoplasma gondii, a parasitic protozoan, can grow inside any animal, but it has to complete the sexual phase of its life cycle inside a cat. An infected mouse loses its fear of cats, is eaten easily and the parasite continues its life cycle. Humans can fall victim to T. gondii, too, and researchers suspect that the parasite might have links to human mental health, including schizophrenia and brain cancer. Scientists say a high level of parasite infection in a society could change entire cultural behaviour.

Some parasites decide the sex of the host. The Wolbachia bacteria infests 70 percent of the world's invertebrates, and has evolved strategies to keep spreading. In female hosts, the bacteria attaches itself to the eggs. Since males are useless for the bacteria's survival, the parasite often eliminates the male embryos to increase the number of females, or turns them into females.

The female crustacean, Cymothoa exigua, is the only parasite known to replace an organ. It enters through the gills of the spotted rose snapper and attaches itself to the base of the fish’s tongue, where it drinks its blood. The bloodsucking causes the tongue to wither away. The crustacean attaches itself to the tongue stub and acts as the fish's tongue. A male will crawl up from the gills and mate with the female inside the fish’s mouth. She then releases her babies through the fish’s mouth who go on to other victims.

The guinea worm Dracununculus medinensis larvae are ingested by water fleas  who enter humans when they drink untreated water. The stomach acid dissolves the fleas, releasing the larvae who burrow through the intestinal wall. Male and female mate with as many as 3 million embryos inside the female at one time. The female slithers down to the human foot. She pierces the skin. Because it burns, the human dunks the foot in water which is exactly what the worm wants. The female then pokes her head out and vomits embryos from her mouth into the water. Those are eaten by fleas and the cycle starts again.

The parasitic fly, known as Apocephalus borealis, injects its eggs into a honeybee's abdomen, where the fly larvae mature. The parasitized bees abandon their hives and walk in circles till they die. The mature larvae burst out from the dead bees' bodies.

A species of baculovirus infects gypsy moth caterpillars and makes them climb up treetops to die. When the caterpillar's body liquefies, the ooze drips down onto other caterpillars — creating more robots.

In the California salt marshes, the fluke Euhaplorchis californiensis reduces the ability of its killifish host to avoid predators. It makes the fish swim close to the water surface where it can easily be swallowed by egrets, a bird the parasite needs to complete its life cycle. Uninfected fish swim far below the surface.

Why do parasites modify host behaviour? Many require several hosts of different species to complete their life cycles and have to rely on predator-prey interactions to get from one host to another. So it is vital that they change the behaviour of infected hosts, to make transmission to other hosts more likely to occur.

Believe it or not, some people intentionally infect themselves with parasites. Patients with diseases like ulcerative colitis swallow worms in an attempt to have them clean up their insides. Could they have had their behaviour changed by parasites who already exist in their bodies? 

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Denis Giles

29 August 2016

Created: 29 August 2016

Last Updated: 29 August 2016

Hits: 1728

By Maneka Sanjay Gandhi

Birds in tropical climates face predators- larger birds, mammals and snakes- who rob their nests, stealing eggs or killing chicks. In a study published in The American Naturalist, scientists report a novel nesting strategy adopted by a tropical lowland bird that inhabits an area with very high losses to nest predators. The newly hatched chicks of the Cinereous Mourner in Peru have downy feathers with white tipped long orange barbs. The nestling moves its head very slowly from side to side in a way typical of a poisonous caterpillar nearby with similar size and coloration as the nestling. The nestling tricks predators into thinking that it is a toxic, spiny caterpillar rather than an edible nestling. This remarkable adaptation decreases nest predation.

Even chickens exhibit intelligent behaviour within just a few hours of hatching. Newly born chicks are able to keep track of numbers up to five.  When given a choice between two groups of plastic eggs they invariably choose the bigger one, even when the decision was between two eggs or three. And their mathematical ability does not end there. In a paper, The Intelligent Hen, spanning 20 years of research, Professor Nicol proves that the birds are born with an understanding of physics – and particularly structural engineering. This is demonstrated by experiments in which they showed more interest in a diagram of an object that could actually be built rather than one that defied the laws of physics.

Experiments also showed that very young chicks understand that an object that moves out of sight still exists. It takes human babies two years to grasp the key concept that out of sight does not mean out of existence. Chicks also show basic empathy and can plan ahead and exhibit self-control until the time is right. For instance, birds quickly learnt that if they waited longer to start eating food, they would be allowed access to it for longer. Further evidence of hen intelligence comes from tests showing that at just two weeks’ old, they can navigate using the sun, something that requires the creatures to take account of the height and position of the sun during the day.

Even newborn ducklings, according to a study in Science journal, challenge our idea of what it means to be a birdbrain.  Zoologists at the University of Oxford devised an experiment. 1-day-old ducklings were exposed to a pair of moving objects. The two objects were either the same or different in shape or colour. Then they exposed each duckling to two entirely new pairs of moving objects. The researchers found that about 70 percent of the ducklings they studied preferred to move toward the pair of objects that had the same shape or colour relationship as the first objects they saw. In other words, a duckling that was first shown two green spheres was more likely to move toward a pair of blue spheres than a mismatched pair of orange and violet spheres. Ducklings go through a rapid learning process, called imprinting, shortly after birth — it’s what allows them to identify and follow their mothers. These findings show that ducklings use abstract relationships between sensory inputs like colour, shape, sounds and smell to recognize their mothers – meaning that an animal baby can learn relationships between concepts without training.

When people want to direct the attention of others, they naturally do so by pointing their hands/fingers. Researchers, reporting in Current Biology, have shown that even baby elephants spontaneously, without any training, get the gist of human pointing and can use it as a cue for finding food. Elephants that were born or kept in captivity were the same as wild-born individuals when it came to following pointing gestures. Scientists say it is possible that elephants may do something akin to pointing as a means of communicating with each other, using their long trunk. Elephants do regularly make prominent trunk gestures and these motions may be "points."

Foals can get up and gallop in the first minute of life. Whale calves can instantly swim with their pod. Puppies understand social hierarchies within a few days of opening their eyes: “who’s moving up or down the social ladder, and who is sleeping with whom.”

What is animal intelligence? Life has taught me that the answers are irrelevant: it is the questions that are important. A new book called “Are We Smart Enough to Know How Smart Animals Are?” by Frans de Waal argues that the mental powers of animals are far more complex than often generally assumed. Many scientists have been asking the wrong questions about animal intelligence, blaming the creature in the cage for poor test results when it’s the person in the lab coat who is flawed.

It’s a mistake to compare animal intelligence to that of humans instead of seeing it on its own terms, he writes. The Clark’s nutcracker, a bird, can remember exactly where it put many of the 20,000 pine nuts it buries each year — but people forget where they put their car keys all the time.

Young bees can solve complex mathematical problems which keep computers busy for days, researchers from the School of Biological Sciences, University of London have shown. The tiny insects are able to calculate the shortest possible route between flowers discovered in random order.

The classic puzzle involves finding the shortest route that allows a travelling salesman to call at all the locations he has to visit. Computers solve the problem by comparing the length of all possible routes and choosing the one that is shortest. Bees manage to reach the same solution. When researchers showed them a bunch of artificially controlled flowers, the foraging bees took one look at the place and were instantly able to figure out the shortest route between them After exploring the location of the flowers, bees quickly learned to fly the best route for saving time and energy.

The author says that chimpanzees might do better at cognition studies if somebody tickled them first, rather than scaring them by separating them from their parents. And the same applies to rats and fish. If you really wanted to know, signs of animal intelligence are all around you. When you eat and abuse an animal you are really eating someone as bright- if not brighter – than you. The only thing that makes the animal “stupider” is that it refuses to learn violence for violence’s sake – something that a human child is taught in its infancy by watching its parents be cruel to the rest of the world.

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Denis Giles

05 September 2016

Created: 05 September 2016

Last Updated: 05 September 2016

Hits: 1879

By Maneka Sanjay Gandhi

There is only one purpose to all life – to reproduce itself. This cosmic order has been given to every cell in every being. It shapes the way we look, think and behave. In order to follow this order, the Universe has designed a variety of ways: reproduction, using a male and female sperm and egg, seems to be the norm. But there are organisms that multiply themselves by splitting; one species that has seven sexes (Tetrahymena)and can multiply with any; species where females or egg layers don’t need males to give birth; species like bacteria where DNA is simply sent across a tube to another identical being. Creative coupling is the order of the day.

In some deep-sea anglerfish species, like the needlebeard seadevil, the tiny male bites into the female, who is often 10 times his size, and soon begins to disintegrate, melting and fusing into her until he’s nothing but testes and a tail sticking out of her side—a sperm supply she’ll use to fertilize her eggs. How do the sperm get to the eggs? Males release sperm and females release eggs, which are then fertilized in the water.

Male squid use a tentacle to stick sperm packets, called spermatophores, on to the heads of females. The sperm burrow into the skin. After that, their route is a mystery.

Dragonfly sperm scrapers are a unique tool in the reproduction game, according to entomologists at the University of Arizona. Before mating, male dragonflies use one penis to scrape the female’s organ and remove the sperm of any prior mating before delivering their own. They then use their other set of genitals and move sperm from the testes into the penis and then mate her.

The male Adactylidium mite technically becomes a father while still inside his mother's body. The mother mite hatches up to nine eggs inside her body, and usually only one is male. This lot lives inside the mother and eats her body. Once matured, the females mate with their brother, then cut a hole in mom’s dead body and leave, while the male dies of exhaustion.

Osedax worms live in the deep sea, where they feed on whale bones. The males are much smaller than the females. They live inside the females and “ejaculate” through the top of their heads, releasing sperm right near the opening where the female's eggs come out.

Flatworms are hermaphroditic sea slugs. When it is time to reproduce, one has to be the bottom and the other the top. To decide, they spar with their penises, and the one who is stabbed receives the sperm and bears the babies.

Some other animals get to be both sexes but not at the same time. The clownfish is born male but it can become female. Clownfish live in groups where only one couple gets to have sex. If the female dies, one of the larger males transforms into a female and the cycle continues. Similarly, some frog species will have members of a population change sex, either from male to female or female to male, in order to maintain the proper proportion of each gender to ensure the continuation of the group.

The New Mexico whiptail is a female lizard of a species that has no males. They don't require fertilisation for their eggs to develop and hatch into new female lizards. However, they undertake mating rituals with each other, one taking a 'male' role, and this has hormonal effects on the other, causing her to lay more eggs. A lizard will tend to take on the male role soon after she's laid her own eggs.

The aquatic Pipa frogs look like someone ran over them. Their breeding is quite unusual. When the female is ready to become a mother, her back becomes very soft like a rotting sponge. The male climbs on the female's back and holds her body with his front limbs. The male and female then turn over in the water. When the female is belly up and the male beneath her she ejects some eggs, the male fertilizes them but collects them between his belly and her back. They turn again and resume a normal "upright" position and the male uses his belly to push those eggs into the spongy back of the female. They keep doing these loops until she's give up all her eggs, and he's pushed them all into the spongy tissue on her back. The eggs develop into froglets on the female's back and emerge.

Male orb-web spiders know they will be eaten by the female during sex. So they have developed an unusual strategy to save themselves. Once they've penetrated the female, they detach their genitalia — structures called palps — and scuttle away, out of the female's reach. The palp continues to deliver sperm until the female manages to pull it out, which can take up to seven hours.

The South American fresh water Copella has a unique reproductive method. The male positions himself underneath some overhanging vegetation and invites a female. When one accepts his invitation,she positions herself directly alongside the male, and the pair leap out of the water together, attaching themselves by fin suction to the underside of a leaf. They produce and fertilise 6-8 eggs, before falling back into the water. This procedure is repeated until as many as 200 eggs are attached to the leaf. The female carries on and the male keeps guard till the eggs hatch.

Most flowers have a relationship with bees and butterflies that helps reproduction. The insects get nectar and in return carry pollen from one flower to the next. Once this happens, the receiving flower starts the process of making the seeds that will grow into new flowers.

Certain species of orchids don’t find this strategy good enough. They don’t want the bee to simply go to the next flower, as this causes inbreeding. In the Mediterranean, a bee orchid, Ophrys apifera, looks exactly like the rear of a female bee, fur and all, with its head buried in a blue-petalled flower. Not only that, Ophrys mimics the scent of the female bee. Male bees fall to mating so vigorously with the flowers that they dislodge pollen packs pre-loaded with a special adhesive, that sticks to their backs. After some frantic efforts at achieving bliss, the bee realizes he has been fooled and flies quite far collecting his wits. By the time he forgets and falls for the trick again; and he has chosen an Ophrys which is far away and so the strategy of the flower, in finding new flowers to pollinate, is successful.

An Australian marsupial, Antichenus, resembles a mouse with the bristly fur of a hedgehog. During the annual mating season, males copulate with many partners one after the other, for up to 14 hours at a stretch. Days later this marathon sex causes the males to develop sores, lose their hair, go blind and finally die of exhaustion.

Hermaphrodite land snails have both male and female sex organs. Once they've selected a likely partner, they flex a muscular sac inside their bodies and eject a dart into the other snail's head, which delivers mucus that readies the snail to receive a sperm packet. Some species jab their mates over and over with their dart, with one stabbing its mate more than 3,000 times. These darts pierce its head completely even hitting the eyestalks.

Male bedbugs use their needle-like penises to puncture the females' exoskeletons wherever they can. Sperm is deposited into the wound, where it travels through her body fluid to the ovaries.

Male bees, after inseminating the queen, die because their testicles explode inside her. Thisis an evolutionary necessity: with the penis inside the female, which seals off any chance of another male getting a mating with her. That is a serious commitment to the future.

Why look at animals for weird, wonderful and scary reproduction. Our own mythology is full of strange examples.

Shiva and Parvati enjoyed an intimate moment and Shiva’s seed fell on the ground. So much heat began emanating from it that it threatened to engulf the world in flames. Agni devoured the vital fluid. He felt so hot that he transferred the fluid to the wombs of six women, called Kritikas, who were turned into stars. They aborted their foetuses on the Himalaya mountains. The holy river Ganga carried the foetuses and Kartikeya was born in the reeds.

Zeus, the head of the Greek pantheon of Gods, swallowed his lover Goddess Metis. A few months later he developed such a headache that he had his head chopped open with an axe. Out jumped his daughter, Athena, goddess of wisdom. 

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Denis Giles

22 August 2016

Created: 22 August 2016

Last Updated: 22 August 2016

Hits: 1570

Maneka Sanjay Gandhi

I think it is possible that what we see as the Universe could simply be a collection of blood cells floating in plasma/ether inside another body. Imagine if we were simply a floating cell in the stomach of a large being. The cells inside us could be worlds of their own and they could have astronomers in there who look at other cells and call them stars. The human body is not a collection of “human” cells. We are a world, a planet, of millions of creatures which are simply not human and which, seen under a microscope cause a normal person to recoil in horror!

More than 70% of the human body is made of other beings. If an artist were to paint a body looking through a sophisticated microscope, what you would see is a hybrid creature like the man-lion-eagle form of mythology, except with many more combinations of beasts. At least 500 species of bacteria, weighing about 1.5 kg, live inside the human gut. Firmicutes and Bacteroides are the main families that live inside your intestine. They break down carbohydrates and make essential nutrients like vitamins K and B12. They battle all the time with the bad bacteria warriors. Good bacteria —notably members of the Lactobacillus family—inhabit the vagina, secreting lactic acid and fending off hostile invaders like Candida albicans.

Microbes, fungi, virus, animals, insects – all of them contribute to making a “human being”. For all the creatures that live in and on us, our bodies are simply food. Like us, bacteria on the surface jealously guard their home and invading bacteria find it difficult to find nutrients and space to grow. Invading bacteria can also be attacked by existing bacteria using chemical warfare.

In fact, you are not even the only animal using your face. In the vicinity of your nose, there are at least two species of microscopic mites living in your pores. Demodex mites are microscopic relatives of spiders and ticks that live in and on the skin of humans. These eight-legged beasts live inside the follicles of the eyelashes, coming out at night to roam over your face feeding on skin cells. Generally, they live out their lives unnoticed. But if they multiply then they cause mange, rosacea and blepharitis in humans. Every human sample of DNA has also shown demodex mite DNA as well. The two species on our faces, Demodex folliculorum (long, skinny) and Demodex brevis (short, chubby), are not even close relatives. We just share the same space. And just as we have different racial traits so do the mites: D. brevis mites from China are genetically distinct from mites from the Americas, East Asians and European populations.

Thousands of different nations of microscopic bacteria- each shaped and coloured uniquely- live on the tongue, teeth, skin and in the intestine. Perhaps strangest of all are the self-replicating, virus-like pieces of DNA that infected ancient humans, and make up about 8 percent of all our genes. Your body is home to 90 trillion or so microbes which live peaceably. And some really bad ones, like herpes simplex who stay dormant for years or human papillomaviruses which cause pimples, boils and warts, cause surface membranes to erupt in nasty pustules or warts. There are more than 100 types of papillomaviruses and they can extend to causing cancers of the cervix, penis, vagina, anus, and rectum.

From time to time bedbugs, fleas, ticks and lice attack. The more common one is the louse that settles down in a schoolchild’s hair, sucks on human blood and cements its eggs to our hair. The human body louse, Pediculus humanus humanus, looks a lot like the human head louse, but it lays its eggs in the seams of clothing. Overcrowded living conditions and lack of access to clean clothes and bedding help infestations spread, causing typhus and trench fever. The 800 species of ticks feed on many hosts, including humans, and they pass along a menagerie of pathogens, from the bacterium that causes Lyme disease to the virus responsible for Colorado tick fever. The human botfly lays its eggs on a mosquito that passes them on to the human. The botfly larvae burrow into the skin and feed on the host's tissue for a month or two before emerging. Bed bugs are tiny, beige creatures that feed on human blood. They pierce the skin of their host with hollow, tube-shaped tongues. Fleas burrow into their host’s skin and suck their blood. They also feed on the faeces of other fleas. Scabies mites don't suck your blood; they eat your skin. Living in burrows just beneath the surface of the skin, scabies mites cause intense itching and a pimply red rash. Although the mites themselves are too small to see, their burrows sometimes appear on the skin as raised ridges. People that live in leech infested areas can get small leeches in their noses or between their fingers/toes.

Here are some of the alien species that enter your body:

Trichophyton and Epidermophyton are filamentous, parasitic microbes that latch onto bare feet. These species creep into the toenails and display themselves as athletes foot. They move higher and reach the scalp and genitalia, where they trigger ringworm and jock itch.

It is estimated that there are over 100 different types of parasitic worms that can be found living in humans. Many are tiny, while others grow long. When small they travel around the blood stream finding suitable places to grow and develop. They can cause diarrhoea, fatigue, skin rash, nervousness, asthma, anaemia and more.

The Guinea worm’s larvae live in the water you drink. Once the larvae get into the stomach, they pass through the digestive track and enter the anus areas where they grow into three-foot-long adults who poke through the skin.

The Filarial worm lives in the human lymph system brought in through mosquito bites. The worms grow into adults, living up to seven years. Although most people with lymphatic filariasis will not develop symptoms, a percentage will suffer from excess fluid in the legs, arms, breasts and genitalia.

The eye worm, or loa loa, comes through deerfly bites and causes itchy swellings . You can see the tiny worm inching its way across your eyeball.

Flatworms include Tapeworms and Flukes. They feed on the blood, tissue fluids, or pieces of cells inside our bodies and range in size from microscopic to 20 metres long. Tapeworms live in human intestines where they feed on the partially-digested food in their host’s intestines.

Roundworms, like Pinworms, Threadworms, Hookworms, Ascaris and Heartworms, have hollow bodies and generally grow between 2-5 inches long.

Some of the smallest animal parasites in the human body are called protozoa. Protozoa breathe, move and reproduce by splitting into two. Amoeba are single-celled animals. They come through water/ food.

See the Documentary “Life on Us”. Are we one species or a collection of thousands of species whose only aim is to strive to multiply.

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