6 Dinosaur myth you must know.

 the first dinosaur bone was described in 1676, it was thought to come from an elephant or perhaps a giant. Over a century later, scientists realised such fossils came from a creature they named Megalosaurus, portrayed as a sort of stocky, overgrown lizard. Then, in 1842, leading anatomist Richard Owen recognised Megalosaurus as part of a whole new group of animals, which he named Dinosauria, or “Terrible Lizards”.

Since then, around 700 different dinosaur species have been described, with more foundever month. Our ideas about dinosaurs have also changed radically. The dinosaurs we know today are very different from the ones in the books you may have read as a child.

3d artist image of the Megalosaurus. Elenarts/Shutterstock

Myth 1: Dinosaurs Were All Big

The name dinosaur tends to evoke images of giants – and certainly many were very large.Tyrannosaurus rex was around 12 metres long and weighed more than five tonnes, the size of an elephant, and it probably wasn’t even thebiggest carnivore. Long-necked, plant-eating sauropods grew to titanic proportions. The enormous Argentinosaurus is known from just a few bones, but its size has been estimated at 30 metres in length and 80 tonnes in weight. That’s larger than any living land mammal and all but the largest whales. And dinosaurs are unique here. No other group of land animals before or since was able to grow as large.

But not all dinosaurs were giants. The horned dinosaur Protoceratops was the size of a sheep.Velociraptor was the size of a golden retriever and had to be scaled up for Jurassic Park to make it more terrifying. Recent years have seen an explosion in the number of small species discovered, such as the
cat-sized raptor Hesperonychus, the rabbit-sized plant-eater Tianyulong, and the quail-sized insect-eater Parvicursor. The smaller species were probably more common than their giant cousins. It’s just that the massive bones of a T. rex are more likely to have been preserved and a lot easier to spot in the field.

Myth 2: Dinosaurs Were All Scaly

When dinosaurs were first discovered, it seemed obvious that because they were related to crocodiles and lizards, they must have been scaly. And many dinosaurs – including duckbills, horned dinosaurs, sauropods, and armoured dinosaurs – dopreserve scale impressions. But in the 1970s, palaeontologists began wondering if some dinosaurs might have been feathered, like their bird relatives.

This was considered wild speculation at the time, but in 1997 a small carnivorous dinosaurnamed Sinosauropteryx was found to be covered not with scales, but a soft, fuzzy down. Since then, feathers have been discovered on the plant-eating ornithopods, fanged heterodontosaurs, and many families of carnivorous dinosaurs including Tyrannosauridae- meaning that T. rex was probably covered in feathers, not scales.

Soft and fuzzy A Gude/Flickr, CC BY-SA

Myth 3: Dinosaurs Were All Green And Brown

Early paintings of dinosaurs favoured a drab palette, with monotone animals dressed in depressing shades of grey, green, and brown. If the Mesozoic era really was that dreary, no wonder they went extinct. But in reality the colours would have been much more vibrant, even garish. Studies of dinosaur scales and feathers have revealed traces of melanin, the same pigment that lends colour to lizard scales, bird feathers and our hair. Analyses show that dinosaurs came in a wide variety of colours including black, white, and ginger. A few show-offs even had an iridescent sheen to their feathers.

Not only that, but many dinosaurs were boldly patterned with spots and stripes, white bellies and dark backs. Some of these patterns probably evolved as camouflage, to help dinosaurs hide from predators and prey. But bright colours and conspicuous patterns would have served to draw the eye of potential mates, much like the tail of a peacock.

Myth 4: Dinosaurs Were Bad Parents

Most reptiles simply bury their eggs and walk away, leaving their offspring to fend for themselves as best they can. This hands-off parenting is risky. A sea turtle must lay thousands of eggs over its lifespan to see a few grow up. Dinosaurs were once thought to use the same “lay ‘em and leave ‘em” strategy. We now know that’s wrong.

Living dinosaur relatives – birds and crocodiles – guard their eggs and their young, so it’s a reasonable assumption that the dinosaurs did as well. And there’s now evidence of this. When expeditions to the Gobi Desert found a dinosaur atop a clutch of eggs, it was assumed to have died while plundering the nest. It was named Oviraptor, or “egg thief”. But then more skeletons were found atop clutches of eggs,sitting on them like brooding birds. It turns outOviraptor didn’t eat eggs —- it was guarding them.

We can go to the gift shop after you’ve eaten Dave Catchpole/Flickr, CC BY

Myth 5: Dinosaurs Were Doomed To Extinction

Dinosaur extinction was long blamed on some failure of the dinosaurs themselves, a failure to adapt to the changing environment. In reality, dinosaurs were diverse for more than 100m years with fossils found in North and South America, Asia, Europe, Africa, and even Antarctica.

Although some argue this diversity was in decline, the fossils show that dinosaurs remained widespread, common and diverse until 66m years ago, when an asteroid struckthe Earth in what is now Mexico. Debris from the impact blocked out the sun and plunged the world into darkness. The disappearance of the dinosaurs wasn’t fated – it was a cosmic accident. If the asteroid had deviated by a fraction of a fraction of a degree, dinosaurs would still rule the planet – and we wouldn’t.

Myth 6: Dinosaurs All Became Extinct

The asteroid wiped out the dinosaurs, almost.T. rex, Triceratops and the rest disappeared, but a handful of small feathered dinosaurs, probably less than a dozen species, survived. They were birds — small, flying cousins of T. rexand Velociraptor and the direct descendants of the carnivorous dinosaurs. And they not only survived but thrived, evolving into some ten thousand species of birds.

10 most deadliest diseases

Whilst it is a ecological necessity that infectious disease pathogens evolve to spread more efficiently there is no obvious reason why some of them wreak such horrific deaths on their hosts. You would think it in a pathogen’s interest to keep its host alive for as long as possible to spread to as many more people as possible. But no. It’s almost as if some sadistic fiend sat down and designed these diseases to instill as much terror on the population as possible.

The list of diseases below are all infectious, all frequently fatal and all very, very unpleasant. The order reflects a mix of how deadly they are and how horrific the symptoms are.

10. Influenza (Flu)

To most people flu is a pretty unpleasant illness contracted 2-3 times in a lifetime. However, influenza was responsible for one of the most destructive pandemics of all time – the Spanish Flu (1918-1919) which killed up to 100 million people. The particular type of flu strain (H1N1) was unusual in that most fatalities where amongst the young and healthy. It seems that the flu actually turned the healthy body’s immune system on itself creating a “cytokine storm” which attacked the lungs.

The most recent flu to hit the headlines was Swine influenza. The alarms bells started ringing when it was found to be a new variant of the H1N1 strain. Deaths did occur and it did seem particularly virulent, but nothing compared to the scale of Spanish flu. I actually had Swine flu and it wasn’t nice.

Perhaps the biggest reason to fear influenza is its ability to combine and mutate to form new strains. Chief amongst these fears is that a super-virulent strain will combine with a highly transmissible strain. This could even happen across species as is the case with the potentially lethal H5N1 Bird flu. Currently bird flu is not able to spread from person-to-person, however, just a small genetic event could open the way for a major epidemic.

9. HIV/AIDS

Human immunodeficiency virus infection / acquired immunodeficiency syndrome (HIV/AIDS) works by effectively destroying the body’s defences to any number of other diseases and infections. There is still no cure or vaccine and until very recently, no effective treatment. To date more than 30 million people have died of AIDS with nearly 40 million currently infected.

HIV increases the chances of picking up infections such as TB, toxoplasmosis and hepatitis. It also raises the possibility of developing several forms of cancer. New treatments with antiviral drugs have increased life expectancy greatly for those with HIV. However, it is the ever changing nature of the HIV virus that makes it so difficult to combat. The virus actually inserts itself into the DNA of the body’s cells, becoming part of your genetic template. Not only that but it evolves rapidly within the body to the extent that evolutionary trees can be made from virus samples taken in different parts of the body.

8. TB (Tuberculosis)

Tuberculosis can affect any part of the body

TB is highly contagious and easily spread through airborne droplets e.g. a sneeze. In fact around a third of the world’s population is actually infected with TB. Fortunately this is in the latent form and is more than likely they will never be aware. Only 1 in 10 cases progress to the active disease which has a 50% mortality rate if not treated. Tuberculosis kills around 1.5 million people worldwide every year, second only to malaria.

The disease primarily affects lungs but can affect any part of body including the testicles (ouch!). The most common initial symptoms are coughing up blood followed by rapid weight loss – this is where the name consumption came from. As the disease progresses large areas of the lungs are necrotized and turned into a cheese like substance. In extreme cases the infection can erode into the pulmonary artery of the lung risking the patient drowning in their own blood.

TB affecting the rest of the body (extrapulmonary tuberculosis) occurs in around 20% of cases. It can affect the nervous system, urogenital system and bones, as can be seen in the photo above where the spine has been infected and collapsed in on itself. In some cases TB can be invade many organs (Miliary TB) affecting the liver, spleen, brain as well as the lungs – this is a particularly serious condition. Ironically most of the tissue damage in TB is caused by body’s own immune system bombarding the infected area with cocktail of chemicals.

Whilst many cases of TB are now treatable with antibiotics new resistant forms are emerging raising the spectre of consumption once again sweeping the world.

7. Anthrax

Anthrax is a bacterial infection which in most forms is lethal. There are three ways in which a person can become infected and this is very important to how the disease progresses. The most lethal way is by inhalation. If not treated this is invariably fatal. With prompt antibiotic treatment still only around half survive.
Anthrax can be ingested, often through infected meat. The initial symptoms of this form include vomiting blood and extreme diarrhea. Outcomes are slightly better if treated with a 25-60% mortality rate.
The bacteria can also spread through broken skin. This causes a dark ulcer and may result in whole limb becoming very inflamed. However, death is rare as the pathogen cannot penetrate beyond skin.

The active ingredient of Anthrax is the imaginatively named “Lethal toxin“, although it is not actually lethal until in combination with edema factor, and protective antigen. Together theses cause wide scale tissue destruction and bleeding with dark, non-clotting blood oozing from bodily orifices. Death occurs within a few days to 2 weeks.

Anthrax is rare but has not been consigned to the history books. In recent years two  cases involving drum skins in US and UK have been reported. The mode of infection here was through the drum skins made from animals being contaminated with anthrax spores. This is one of the scariest things about anthrax it can exist as dormant spores which may survive for 100s of years. An island in Scotland was rendered uninhabitable for 50 years after anthrax experiments by the British government. It had to be decontaminated before anyone could return. It is very difficult to eradicate anthrax spores with burning being one of the few options.

Obviously something this deadly attracted the military and anthrax was weaponized by both US and USSR. In Russia 68 civilians were killed  in the 1979 Sverdlovsk incident when weapons grade anthrax accidentally leaked. Bioterrorism is also a possibility with a series of fatal postal attacks in carried out in the USA in 2001

6. Cholera

Cholera is one of the most infectious diseases and is easily passed through contaminated food and water. Historically it has ripped through communities leaving half dead, even now it is estimated to kill 120,000 per year. In the past epidemics killed millions.

Cholera kills through rapid dehydration. The symptoms are non-stop vomiting and diarrhea until you can’t anymore – and then some more. One estimate suggest patients can produce up to 20 litres (5 US gal) of diarrhea a day. What is tragic about the disease is it is very cheap and easy to treat with fluids and electrolytes. When treated only 1% of cases result in death; untreated there is an over 60% chance of fatality. The most virulent strains of cholera can kill within 2 hrs if the patient is left untreated.

5. MRSA

MRSA, or Methicillin-resistantStaphylococcus aureus to give it its full name, is particularly scary as it renders modern medicine ineffective. The so called “Superbug” has the ability to plunge us straight back to the Dark Ages where peasants were afflicted with all manner of boils and hideous skin diseases! But MRSA is more than just a skin infection it has been known to kill within 24hrs.

There are a number of  strains of MRSA with some much more virulent than others(ST1:USA400 and ST8:USA300). But they all have one thing in common; they are resistant to a wide range of the most commonly used antibiotics that are available to mankind. In theory they should produce the same symptoms as a standard staph infection, and most of the time they do. However, not only are they not easily treatable, but in many cases appear much more pathogenic than their non-resistant relatives.

Conditions associated associated with MRSA include:

Necrotizing fasciitis  – a flesh eating condition affecting deeper layers of  the skin.
Toxic shock syndrome  – a systemic infection that can be fatal.
Necrotizing pneumonia – flesh eating infection of the lungs.
Osteomyelitis – a painful bone infection.
Sepsis – a potentially fatal infection of the bloodstream
Endocarditis – infection of the heart

MRSA can effectively eat your body with very few available antibiotics effective – and resistance growing. It seems that the antibiotic era is drawing to an end and much of this is down to people misusing and overusing them.

4. Rabies

Rabies is invariably fatal if not treated immediately after bite. If intervention only occurs after the symptoms start showing there is an 8% chance of survival. Worldwide rabies kills around 55,000 people, mostly in Africa and India, but it does still exist in the US and Europe.

Rabies first infects the central nervous system and ultimately causes disease in the brain leading to death. Symptoms include acute pain, violent movements, uncontrolled excitement/mania and hydrophobia. This is seen as panic when the patient is given liquids to drink even when thirsty and triggers excruciatingly painful spasms of the muscles in the throat. Perhaps the best known symptom though is the foaming at the mouth caused by the excessive production of saliva.

The incubation period for rabies varies greatly from a few days to several years. Unfortunately once symptoms begin death occurs within 2-10 days.
Rabies can be carried by any warm blooded animal,but in the vast majority of cases it is a bite from a dog that is the source.

3. Smallpox

Smallpox is possibly the most horrific looking of any disease. The classic symptom is the body being covered in pox, fluid filled pustules. This isn’t limited to the skin either they can occur in the mouth and throat. The disease has been around since 10,000 BC and was responsible for 300 million deaths since 1800 alone.

Whilst the mortality rate is only around one third most survivors suffer some scarring with other complications including blindness. The number of deaths is high though because smallpox is incredibly contagious.
The mortality rate depends on the course the disease takes. Of the four forms malignant and hemorrhagic smallpox are usually fatal. In hemorrhagic smallpox, most serious form, there is no blistering of the skin, instead there is bleeding under skin causing it to turn black. Given the name “black pox” this form would  kill in around 6 days.

The good news about smallpox is it has been officially eradicated. The world has been free of smallpox since 1976 with the last recorded case two-year old Rahima Banu in Bangladesh.

Of course the deadly potential of smallpox was recognised by the military. It was first used as a bioweapon by British as early as 1789 against Australian aborigines. Weaponized by Soviets during the Cold War it now only exists in laboratories. One worry is smallpox could potentially be re-engineered from digital viral genome and inserted into related pox virus.

2. Bubonic Plague

If any disease can evoke pure terror then it is Bubonic Plague. Responsible for the Black Death which swept Europe in the middle ages killing an estimated 100 million people. There have been other plague epidemics including one in the 6th century which killed 50 million throughout the Roman Empire.

The plague is spread by a bacteria carried by rat fleas, unfortunately for them it kills them too. Symptoms occur within 2-5 days of a bite;  initially the lymph glands nearest the flea bite swell up like golf balls (buboes). Further symptoms include cramps, seizures and even vomiting blood. Acral gangrene at the extremities causing fingers, toes and noses to turn black are common and the skin may become very discoloured. This is where the name “Black Death” came from. In the latter stages there may be extreme pain caused by skin decaying on the living person.

Bubonic Plague (Yersinia pestis) still exists and sporadic cases occur even in the USA. There have been major outbreaks as recent as 1946 but nothing on the scale of the great plagues in history. The (relatively) good news is it can be effectively treated if antibiotics are given within 24hrs. Otherwise the mortality rate is in excess of 60% .

Naturally the military would not miss out on a chance to utilise something as terrifying as the plague. It is in fact one of the first ever biological weapons having been used in the 14th century. In this case diseased corpses were catapulted over the walls of besieged cities. The Japanese also used weaponized bubonic plague against the Chinese in World War II.

1. Ebola

Ebola is highly contagious with evidence that it can be spread via air. There is no treatment. There is no vaccine. Agonising death has been known to occur in excess of 90% of cases in some outbreaks. For these reasons the Ebola virus trumps any current disease to become the deadliest infectious disease on the planet.

Ebola is actually a group of viruses all of which are native to central Africa. The first reported cases in the mid-1970s appear to have been related to the local taste for bush meat, i.e. indigenous wildlife. One of the scary thing about Ebola is nobody is certain where it came from. And nobody knows for sure where it exists. It is assumed there is a natural reservoir of the virus within some animal population, but the species is unknown.

Infection with Ebola starts out with pain practically everywhere;  joints, muscles, abdominal cramps, headaches. Various rashes usually also appear. Ebola interferes with the blood’s clotting mechanism and bleeding may occur from every orifice.  Near inevitable death is usually caused by multiple organ failure and internal tissue necrosis.
Surprisingly, of those who do survive many make a complete recovery. It is worth noting though that the Ebola virus can be transmitted via semen up to 12 weeks after an infection.

In the post Cold War era no government has taken it upon themselves to try and turn Ebola into a weapon of war. But with its great potential to kill horribly it has been judged a category A bioterrorism agent.

Symptoms of head lice.

A lice infestation can be asymptomatic for two months before itchiness of the scalp occurs.

Itchy papules develop and these often become infected from scratching, resulting in infection of the scalp. The lymph nodes at the back of the head and in the neck are frequently enlarged. The eyelids can also be involved.

In adolescents, pubic and axillary hair may be infested.

Other symptoms of head lice include:

- A tickling sensation like something is crawling in your hair

- Intense itching that causes red bumps due to an allergic reaction to the saliva that lice inject while feeding

- Lice nits that resemble tiny buds which can be mistaken for dandruff

The doctor will diagnose head lice by using a special light, called Wood's light under which the nits appear pale blue.

Using a fine-toothed comb is also another effective way of identifying head lice. Stroke it from the crown of your head downward over the scalp at least twice.

However, finding nits this way doesn't mean that there is a live active infestation. The best way to identify an infestation is if you find a live louse.

8 facts you should know about pubic lice.

Below are some facts about pubic lice.

1. The name “crabs” refers to the crab-like appearance of public lice. The louse has a rounded body, six legs, some of which have claws which help it hang onto coarse pubic hair.

2. The most common symptom of crabs is itching in the pubic area. This itching is caused by an allergic reaction to the bites, and usually starts about five days after a person gets crabs.

3. Much like head lice, crabs cannot jump; they crawl from one host to another.

4. Pubic lice found on children’s eyelashes may be a sign of sexual exposure or abuse.

5. When you have pubic lice, it’s advisable to get tested for other STI’s. A check-up is usually recommended as a precaution. 

6. The “ITCH” usually start at night because pubic lice tend to burrow when their host isn’t moving around too much.

7. Excessive scratching has been found to cause secondary bacterial infections.

8. The only other animal known to be affected by this wingless terror is the gorilla.

Pubic lice

10 facts you should know about Zika.

Many people, however, don't know what all the fuss is about, how it affects us and if we should be worried at all.

Here are 10 facts about Zika:

1. The word “Zika” refers to a virus. The virus belongs to the family Flaviviridae and the name derives from the Zika forest in Uganda where it was isolated in 1947 in monkeys. It was identified in humans in 1952 in Uganda and Tanzania.   

2. The Zika virus is spread to humans mainly through the bite of an infected Aedes aegyptior Aedes albopticus mosquito. These are the mosquitoes that also spread the dengue and chikungunya viruses. They usually bite during the daytime. Zika virus infection can be confirmed by laboratory tests on body fluids like blood, urine, saliva or semen.

3. Before 2015, Zika outbreaks occurred in parts of Africa, Southeast Asia and the Pacific islands. It has since spread to Brazil and, according to the WHO, from 1 January 2007 to 6 April 2016, Zika virus transmission was documented in a total of 62 countries and territories. The virus is likely to continue spreading and it is difficult to predict where it will spread to and how long it will take.  

4. The symptoms of Zika virus disease are similar to dengue, and include:

• Fever
• Skin rashes
• Conjunctivitis
• Muscle and joint pain
• Malaise
• Headache

Symptoms tend to be mild and last for two days to a week. The incubation period is estimated to be a few days. There is currently no drug treatment or vaccine for Zika virus disease.

5. Known complications of of Zika virus disease, according to the WHO, are microcephany and Guillain-Barré syndrome. There may be a link between the Zika virus and a number of neurological disorders. Microcephaly is a birth defect where babies’ heads are smaller than those of their peers. It is also associated with incomplete brain development. Guillain-Barre syndrome is a condition where the immune system attacks nerves, leading to muscle weakness and sometimes paralysis.

6. The Zika virus can also be transmitted:

• From mother to child. A pregnant mother can pass the Zika virus to her foetus while she is pregnant.  
• Through sexual contact. The virus can be spread by a man to his sex partners.
• Through blood transfusion. There have been a large number of blood transfusion cases in Brazil and the virus has been found in blood donors in other countries.
• Through laboratory exposure. There have been four reports of laboratory acquired Zika virus infections.

7. South Africa is not likely to be at risk of Zika, according to The National Institute of Communicable Diseases (NICD) – even though Zika virus disease is spreading explosively in the Americas. (The Zika virus tends to favour tropical regions.) Professor Lucille Blumberg, a deputy director at the NICD, however, warns that pregnant women should be careful about going abroad, especially to Brazil. 

8. Because Zika can be transferred though sexual intercourse, couples and individuals returning from Zika-affected areas should practise safe sex for at least eight weeks.

9. Zika is not the end of the world. Although ithas been declared “a global public health emergency” by the WHO, as stated above, most people who contract Zika virus disease have very mild symptoms. The link between the Zika virus and microcephaly has also not been conclusively proven, only "strongly suspected".

10. There is definitely no need for the Olympics to be cancelled, postponed or moved. In response to the news that golfer Rory McIlroy withdrew from the Olympics over Zika fears, an expert said that only pregnant women and people planning a family need fear Zika.