Drugmakers consider using venom to treat cancer, diabetes and pain

Captopril, an angiotensin-converting enzyme inhibitor that imitates venom of South American pit viper, was approved by FDA in 1980

Could snake or insect venom yield the next big treatment for diabetes or cancer?

Researchers think so ⁠— and they’re spending lots of time with compounds found in the venom of animals such as scorpions, snakes and snails in the hopes they’ll yield new drugs.

In a feature for the journal PNAS, Amy McDermott explores the trend and its fascinating history.

The science behind venom-derived drugs is complex ( Getty )

“The pharmaceutical industry has a growing interest in venom, as some companies opt to return to drug discovery inspired by natural compounds, a trend that fell out of fashion about 40 years ago,” she writes.

Captopril, an angiotensin-converting enzyme inhibitor with an ingredient that imitates the venom of a South American pit viper called jararaca, was approved by the Food and Drug Administration in 1980. Today, it’s one of 10 approved drugs that mimic the compounds that make the bites of snakes and other creatures so effective.

McDermott explores venom’s fall from scientific favour, which researchers attribute to the complexity of the compounds. 

It’s difficult to target drugs to specific body systems without causing havoc in other systems, and researchers are facing thornier challenges as they try to harness venom’s best qualities ⁠— the ability to act on specific biological pathways.

Serious roadblocks remain, but they’re being overcome by a new generation of scientists who think they can tackle the chemistry challenge.

The science behind venom-derived drugs is complex, but McDermott makes it accessible ⁠— and points to intriguing possibilities for patients with cancer, diabetes, arthritis, pain and more. For now, those advances slither just out of reach. 

But if the scientists she interviews have anything to do with it, they’ll soon turn toxins into medical treasures.

(Source: Independent)

Why are so many people still dying from snake bites?

Tens of thousands of people die from snake bites worldwide every year. Lack of treatment and even the wrong medicine mean many of these deaths are preventable.

Snake bites may not strike you as being a major public health problem.

But in some parts of the world they are a daily risk, and can be lethal or life-changing.

Victims often do not get the treatment they need in time, if at all.

In other cases, they are given medicine to treat an injury caused by a different snake.

About 11,000 people a month are thought to die from venomous snakebites - similar to the number that died during the whole of the 2014-16 West Africa Ebola crises.

A further 450,000 people a year are thought to suffer life-changing injuries such as amputation and permanent disability.

The scale of the problem means snake bites are now classed as a priority neglected tropical disease.

Who gets bitten?
In developed regions - such as Europe, Australia and North America - snake bites kill only a handful of people each year, despite there being many venomous species.

That is compared with 32,000 deaths in sub-Saharan Africa, and twice as many in South Asia.

Children walking to school can be at risk of snake bite

Many rural communities in the tropics are at almost constant risk of snake bites, whether working in the field, travelling at dusk or even sleeping in their homes at night.

Young male farmers are the most at-risk group, followed by children.

While a large rural population is a factor, health systems in some parts of Africa and Asia are often ill-prepared for coping with snake bites.

Clinical training, emergency transport and affordable medicine are often in short supply, with tragic consequences.

Expensive medicine
Venomous snake bites typically cause three main types of life-threatening symptoms: uncontrollable bleeding, paralysis and irreversible tissue destruction.

It is essential for snakebite victims to get the correct medicine as soon as possible following a snake bite.

Antivenom is the medicine of choice for treating snake bites.

It is made using the venom of the snake it is designed to treat.

This means that many different versions are needed, because there are so many venomous snakes found throughout the world - cobras, mambas, kraits, vipers and pit vipers, to name just a few.

The toxins found in their venom differ from one group of snakes to the next, or even between the same group of snakes in a different region.

This means the correct antivenom is often hard to identify and can be very expensive.

In Latin America, antivenom is often produced in the country and subsidised by the government.

A juvenile pit viper

Death rates are significantly higher in sub-Saharan Africa, where the best antivenom costs $140 to $300 (£108 to £233) per vial, with three to 10 vials usually required to save a victim's life.

As the typical Swazi farmer earns $600 a year, this medicine out of reach for most.

The wrong antivenom
This situation has allowed weak or inappropriate medicine to flood the market over the past decade, particularly in Africa.

These antivenoms often cost about $30 per vial - a fraction of the cost of proven products.

Some African health ministries understandably saw this as a win-win situation, with more drugs available and at a lower cost.

These products started being used in hospitals throughout much of the continent.

However, there are now several reports that some of these medicines may be dangerously ineffective.

Small-scale case studies from hospitals in both Ghana and Central African Republic have suggested that when these cheaper medicines were used, fatality rates increased from 2% or fewer, to more than 10%.

Often, these antivenoms are made using snake venoms from a different region to where the product is being sold - for example an antivenom made with Indian snake venom being used in Africa.

Others are made with the right venoms, but with a low concentration of antibodies per dose - resulting in very weak medicines.

This means the number of vials needed to successfully treat the patient shoots up from three to 10, to as many as 20 or 30.

An eyelash viper

Ironically, this situation has prompted some established manufacturers to cut supply of their much-needed products as they became priced out of the market.

Lack of testing
These problems have been made worse by the lack of antivenom testing.

Most drugs have to be thoroughly independently tested, with clinical trials to prove their effectiveness.

But this often is not the case with antivenom. National drug agencies sometimes approve products without strong evidence of their effectiveness, or comparison with existing treatments.

To tackle this, the World Health Organization has launched a pre-market testing scheme, with the results due to be published later this year.

This should allow health ministries, pharmacists and clinicians to better understand which antivenoms are suitable for their region, while identifying responsible manufacturers of affordable antivenoms.

However, manufacturers do not have to take part in the scheme, and countries are not obliged to remove products from the market based on the results.

Nevertheless, it is hoped that this World Health Organization seal of approval will strongly influence antivenom purchasing decisions throughout Africa.

Looking to the future
Effective antivenom is one part of solving the snake bite puzzle, but many other challenges remain.

More work needs to be done to identify the communities most at risk and to ensure a sustainable flow of affordable medicine is sent there.

Meanwhile, training more clinicians and healthcare workers in how to effectively treat snake bite victims would reduce the number of deaths.

Finally, educating local communities about snake bites would help lower the risk of being bitten, and mean appropriate action was more likely to be taken after a bite.

How antivenoms are made

• A tiny non-harmful amount of snake venom is injected into an animal - usually a horse, or sheep
• This stimulates the animal's immune system to create antibodies that neutralise the venom
• These antibodies are extracted from the animal's blood, purified and made into antivenom
• Antivenoms must be used in hospital because of patients suffering a high rate of adverse reactions to the medicine

(Source: BBC)

A snake named Toothless got braces to fix her overbite

A green tree python named Toothless recently broke a part of her jawbone while eating.

According to a Facebook post from HerpVet, an animal hospital in Mount Ommaney, Australia, specializing in reptiles, Toothless was in the middle of enjoying her dinner when "Somehow, during the swallowing process her left lower jawbone folded and got stuck on her throat."

The python was left with an overbite and a resemblance to a vaguely perturbed Muppet. Seeing their animal in distress, Toothless's owners rushed her to the hospital where an X-ray revealed a break in her jawbone.

HerpVet

9 September at 09:23 · 

Happy Sunday!
Meet Toothless the green tree python (Morelia viridis). She presented as an emergency consult due to a feeding mishap. Some how, during the swallowing process her left lower jaw bone folded and got stuck on her throat. She had recently laid her eggs and this was her first feed post deposition which may have weakened her jaw making it more susceptible to fracturing. After delicately dislodging the stuck portion of the jaw, it was still abnormally positioned. An x-ray image was taken to assess the bone and a break was see in the mandible (arrow). This bone is too small and fragile to fix with traditional surgery, so the bone was aligned and an external brace (a moulded paper clip) was attached. After falling off the next day, the external brace was reapplied. This stayed on until she shed and this was long enough to allow her to heal. The final image was at her recheck appointment. She was given pain relief and placed on a calcium supplement to aid in the healing process. Food will be with held for a couple of weeks at which point a final x-ray will be taken to confirm healing has completed.

Surgery would have been risky, as the bone was too small and fragile to mend using traditional methods. So doctors came up with a truly visionary solution: Braces. Snake braces.

The veterinarians realigned Toothless' jaw and used a paperclip to craft an external brace, affixing it to her scales using a non-toxic super glue. It fell off the next day but was reapplied. This time, it stayed on "until she shed and this was long enough to allow her to heal," wrote HerpVet.

Doctors also posited that the python broke her jaw in the first place because she'd recently laid eggs, which weakened her jaw and made her mandible bones more susceptible to fracturing.

"She was given pain relief and placed on a calcium supplement to aid in the healing process," the doctors explained. "Food will be withheld for a couple of weeks at which point a final x-ray will be taken to confirm healing has completed."

Here is Toothless, all healed up at her final checkup, with "only a single damaged scale to show anything ever happened."

"Thank you so much for fixing my Toothless up!" owner Bo Marsh commented on HerpVet's Facebook post. "She's feeling much better and constantly begging me for food. She's gonna have to wait a bit longer! 🤣"

(Source: Insider)

IIT Delhi’s new anti-venom cuts cost from Rs 500 to Rs 70, spells boon for Kerala!

About 300 species of snakes are found in India of which 10 are venomous. Among these 10, the Big Four—Indian Cobra, Common Krait, Russell’s Viper and Saw-Scaled Viper—are the deadliest.

Scientists in IIT-Delhi, in association with the San Jose State University, USA, have developed a cheaper, much more effective anti-venom to snake bites.

Incidentally, this invention in Delhi will be a great help to the people of Kerala.

As the floodwaters in Kerala recede, people are finally returning home, only to be welcomed by snakes hiding in the nooks and crannies inside.

About 300 species of snakes are found in India of which 10 are venomous. Among these 10, the Big Four—Indian Cobra, Common Krait, Russell’s Viper and Saw-Scaled Viper—are the deadliest and are responsible for causing the highest number of snakebite-related deaths in India, while the venom of the remaining six is capable of making you unconscious.

Currently, the anti-venom used in India is a horse serum that is immunised with snake venom.

Each vial of the anti-venom costs about Rs 500. However, this also comes with its share of medical risks. For example, if you are bitten by an Indian Cobra and are immunised with this anti-venom, you might still develop a reaction to the anti-venom of the other three snakes, or the horse serum.

IIT-Delhi recently found the perfect solution to this. They developed the Lethal Toxin Neutralising Factor (LTNF) which is a peptide-based treatment that eliminates the risk of allergic reaction to horse serums.

GiveIndia and The Better India have come together to help Rebuild Kerala by supporting 41,000 affected families. You too can be a part of this movement and help us raise funds for the NGOs working to rehabilitate these families. If all of us come together with a small monthly contribution, we can make a real and meaningful difference in helping restore normalcy to those who need our help the most.

Source: Matrubhumi News.

Professor Anurag Rathore, a member of the chemical engineering department, told Hindustan Times, “This is a polyvalent anti-venom, which will be effective against a bunch of snake bites, unlike the ones currently available that are effective against only the big four. We have already shown its efficacy in two of the four snakes in mice model(s), and the other two are underway.”

This new anti-venom developed in Delhi will also be much cheaper than its current counterpart.

The IIT scientists are aiming to sell it at the rate of $1 (around Rs 70) per dose. Apart from a low cost of the medicine, the scientists have also tackled another important issue for the anti-venom— that of transportation.

“Serums are not very heat-stable and need to be stored in the correct cold-chain conditions for them to work. This makes transport and storage a problem in semi-urban and rural areas, where most of the snake bites occur,” he told the publication.

Speaking to NDTV, Rathore said, “The LTNF that we are proposing can be stored at room temperatures for several years. We have genetically manipulated the E. Coli micro-organism to make this peptide. When the E. Coli grows, it releases the peptide itself which we purify later.”

The LTNF will be in powdered form, making it far more stable than liquid anti-venoms. The professor said that it could be mixed with saline at the time of administration, letting it flow into the bloodstream—where venom affects a person.

Stable, cost-effective and easy to use, this development by IIT Delhi certainly promises to be a blessing for trekkers, wildlife enthusiasts, farmers, Kerala flood victims and anyone who runs the risk of being bitten by a venomous snake. If you find a snake in your house in Kerala, you can call these helpline numbers.

(Source: TBI)

How a giant python swallowed an Indonesian woman

An Indonesian woman has been killed and swallowed whole by a 7m (23ft) long python, say local authorities.

Though such incidents are incredibly rare, this was the second python death reported in Indonesia in just over a year.

What happened to the woman?
Wa Tiba, 54, went missing last Thursday while checking on her vegetable garden on Muna island in Sulawesi province. A huge search was mounted by local people.

Her sandals and machete were found a day later - a giant python with a bloated belly was lying about 30m away.

"Residents were suspicious the snake swallowed the victim, so they killed it, then carried it out of the garden," local police chief Hamka told news outlet AFP.

"The snake's belly was cut open and the body of the victim was found inside."

Gruesome footage has been circulating on social media in Indonesia showing the woman's body being recovered intact in front of a large crowd.

How do pythons attack?
The python in Sulawesi is believed to have been a reticulated python.

They can reach lengths of more than 10m (32ft) and are very powerful. They attack in an ambush, wrapping themselves around their prey and crushing it - squeezing tighter as the victim exhales.

Reticulated pythons are usually said to avoid humans

They kill by suffocation or cardiac arrest within minutes.

Pythons swallow their food whole. Their jaws are connected by very flexible ligaments so they can stretch around large prey.

When it comes to eating humans, "the restricting factor is human shoulder blades because they are not collapsible," Mary-Ruth Low, conservation & research officer for Wildlife Reserves Singapore and a reticulated python expert, told the BBC in an earlier interview.

Do they eat other large animals?
"Pythons are almost exclusively mammal feeders," Ms Low points out, though they do occasionally eat reptiles, including crocodiles.

Typically they eat rats and other small animals, she said, "but once they reach a certain size it's almost like they don't bother with rats anymore because the calories are not worth it".

"In essence they can go as large as their prey goes."

That can include animals as large as pigs or even cows.

Sometimes the size of the meal can be misjudged. In 2005 a Burmese python - the largest in the python family - tried to swallow an alligator whole in Florida. It burst in the process and both died, their bodies later being found by rangers.

But these opportunistic hunters can be surprisingly picky too. If they don't see suitable prey, they can go for long periods on very little food until they see something big enough.

Is this the first time a python has eaten a human?
No. In 2002, a 10-year-old boy was reportedly swallowed by a rock python in South Africa.

And in March last year - also in Sulawesi - a farmer was swallowed by a 7m-long python.

The 25-year-old from West Sulawesi was on a palm oil plantation near his village when he was attacked. Video footage showed his body being extracted.

Video showed the snake being cut open with a long knife to free the man's body

Also last year, a man from the Indonesian province of Sumatra managed to fight off a 7.8m-long python who had attacked him while he was on a palm oil plantation. He survived with serious injuries.

Previous claims often involved hard-to-prove cases that happened some time before they were reported, in remote areas and without reliable witnesses.

Anthropologist Thomas Headland, who spent decades among the Agta, a group of hunter-gatherers in the Philippines, had claimed that a quarter of the tribe's men had been attacked by reticulated pythons at some point.

Though almost all fended them off with machetes, adult Agta - who are physically small - were occasionally eaten, his research said.

Snake expert Nia Kurniawan from Indonesia's Brawijaya University, told BBC Indonesia that pythons are sensitive to vibrations, noise and heat from lamps, so they normally avoid human settlements.

The latest victim's garden was located at the base of a rocky cliff littered with caves, known to be home to snakes, according to the local police chief.

The reticulated python (Python reticulatus)

• The longest snake in the world, capable of reaching over 10m (32ft) in length.
• The longest in captivity is held in Kansas City, US, and measured 7.6m (25ft) in 2011, according to Guinness World Records.
• If often lives in forests, is normally fearful of humans and is rarely seen.
• Is often treated as a sacred animal in parts of Indonesia when caught.
• Dozens of other python species are found in sub-Saharan Africa, Australia, Nepal, India, Sri Lanka, Burma, China, and across South East Asia.

(Source: BBC)

Venomous sea snake found off California: How did it get there?

The yellow-bellied sea snake usually roams the world's tropical oceans.

The yellow-bellied sea snake has the widest range of any snake on the planet. And if the last few years are any indication, its range might be getting even bigger—thanks to climate change.

In January, one of the highly venomous, brightly colored serpents washed up on southern California's Newport Beach—only the fifth such snake ever recorded in the region.

Native to the world's tropical oceans, the reptile was several hundred miles north of its typical range, from southern Mexico north to Baja California. It follows three others that washed up in the winters of 2015 and 2016, and a fourth from 1972.

The yellow-bellied sea snake found on Newport Beach was close to death and humanely euthanized. 

The previous four snakes all had something in common: They washed up during El Niño years, when ocean currents change and sometimes carry unwitting species far from home.

"Currents are doing weird things, and ocean temperatures are much warmer, so that kind of makes a lot of sense," says Greg Pauly, a herpetologist at the Natural History Museum of Los Angeles County.

What makes less sense is why one would show up in 2018, which is not an El Niño.

THE OCCASIONAL WAIF
The yellow-bellied sea snake is the only sea snake that lives in the open ocean, feeding on small surface fish and floating on currents, according to University of Florida biologist and sea snake expert Harvey B. Lillywhite.

The animals survive by drinking rainwater that falls on the sea surface, and give birth to live young—typically three to six offspring at a time—right into the water.

The species is happiest in waters above 65 or 66 degrees Fahrenheit; any colder and they're unable to digest food. Still, because ocean currents largely dictate their movements, the reptiles sometimes float outside of their preferred habitat, Lillywhite explains.

"So periodically one will show up in New Zealand, one will show up in California. What we're talking about is the appearance of an occasional waif," Lillywhite says.

Greg Pauly holds the sea snake on January 9. The venomous reptiles live in tropical oceans the world over. 

CURRENT EVENTS
The Davidson Current runs from south to north deep below the surface about 10 to 20 miles off Baja and southern California, along the edge of the continental shelf.

From October through February, the current rises toward the surface, where it can pick up snakes floating near Baja and scoot them northward. Historically, there haven't been a lot of snakes along Baja's Pacific Coast to begin with.

But Pauly suspects that warming waters are causing yellow-bellied sea snakes to creep northward along the Pacific coast—increasing the chances that more animals get swept up into the Davidson Current.

"This is all speculation," he admits, but it's one that Lillywhite agrees with. "With global warming, we anticipate that some sea snakes' ranges are going to expand," Lillywhite says.

It makes sense that climate change would affect wide-ranging, open-water species first, says Pauly. Take the brown booby, an open-water seabird.

"For decades [it] has been moving northward up the Pacific coast, and just this past November was documented on this little chunk of rock off the Channel Islands," he adds.

FUN... BUT TERRIFYING
Stressed out, exhausted, and with bodies ill-suited for slithering on sand, yellow-bellied sea snakes are usually dead or dying by the time a beachgoer notices them.

On the day the most recent snake washed up, the local sea surface was a frigid 61 degrees Fahrenheit—likely why it was close to death.

The animal was first reported to biologists at the Pacific Marine Mammal Center, who then contacted Pauly.

Humanely euthanized and added to the collections of the Natural History Museum of Los Angeles County, the specimen could help biologists gain insight into how climate change may be altering wildlife communities off southern California.

"On the one hand, I'm pretty excited that we've got yellow-bellied sea snakes showing up off of the coast. As a herpetologist, that's kind of fun," says Pauly.

"But the underlying cause is pretty terrifying."

The dark price that a sea snake paid to live in a polluted world

Animals do the most amazing things. This is the first and only evidence of a snake changing its colour in response to industrial contamination, writes  Janaki Lenin on the Wire. Read on: 

Turtle-headed seasnakes (Emydocephalus annulatus) in polluted waters are changing colour. Creatures of the Indo-Pacific coast, they usually have high contrast black and white bands or blotches encircling their bodies from head to tail.

While snorkeling in the shallow Nouméa lagoon of Grande Terre Island, New Caledonia, more than 1,000 km east of Australia, evolutionary biologist Rick Shine of the University of Sydney and his family observed unusually black turtle-headed seasnakes. Back then, in 2003, males, the smaller of the sexes, seemed more prone to melanism (80%) than females (54%). These waters are polluted by runoff from nickel mining, the largest employer in this French protectorate. Besides the black seasnakes, Shine observed some retained faint bands. What’s causing the startling white rings to disappear?

A black turtle-headed seasnake sloughing its skin. Credit: Claire Goiran

Dark colours absorb heat, a useful trait for land reptiles in cold countries. But dark aquatic snakes gain no advantage because water is not a conductor of heat, says Shine. Nonetheless, entire populations of black individuals frequent the waters of Saumarez and Ashmore Reefs, Australia. However, in New Caledonia, the banded phase is prevalent and black snakes were not common in earlier years.

Turning black in response to pollution, a phenomenon called industrial melanism, afflicts many creatures, chief among them insects. With soot settling on their environment, several species of light-coloured moths stood out and became an easy meal for insectivorous birds. A surfeit of melanin turned some of them coal black. Since these insects matched sooty surfaces, they evaded predators. First recorded in 1848 in Manchester, UK, dark peppered moths (Biston betularia) became common within 50 years, almost replacing the speckled light phase.

However, black turtle-headed seasnakes don’t restrict themselves to backgrounds that match their body colour. When banded creatures move, they create an optical illusion: They seem to travel in the opposite direction and thus evade their killers. So losing bright bands wouldn’t be to the turtle-heads’ advantage.

Nor could black confer any advantages in catching prey. All males, females and the young scrape fish eggs off coral, and they don’t have to lie in ambush since their meals aren’t about to escape by swimming away.

“Initially I thought it might relate to habitat differences and camouflage; then perhaps mate choice and sexual selection,” Shine told The Wire. “But we gathered a lot of data, and neither of those two ideas worked out.”

What then could be the reason for the colour change? The explanation for why snakes of the same species living in the same lagoon have different colours had to wait 14 years.

In 2014, researchers from France published a study of pigeons becoming darker because of pollution. It wasn’t a result of soot settling on the Parisian birds’ plumage and making them dusky. Instead, contaminants such as zinc stuck to melanin in the darker feathers. This ability to detoxify their internal organs of harmful chemicals by shunting them to their feathers allowed dark-coloured birds to become more successful in cities than pale ones.

“I read the pigeon paper shortly after its publication, and I immediately thought that the link between pollution and melanism could explain why so many Emydocephalus annulatus were black,” Claire Goiran, a marine biologist at the University of New Caledonia, Nouméa, told The Wire.

(A) Emydocephalus annulatus (melanic specimen sloughing). (B) Melanic and banded E. annulatus from a peri-urban population near Noumea. (C) Frequencies of melanism in snakes from urban-industrial sites versus other areas.

Goiran and Shine compared 1,400 specimens that Shine had collected over 13 years. The samples came from the polluted waters along the coast of New Caledonia and the clear seas of Barrier Reef atoll in Australia. An overwhelming majority of the black seasnakes came from contaminated waters, while the ones in non-industrial areas had stark bands.

When pollutants enter their systems through their diet, they collect in the snakes’ skins. For instance, the shed skins of corn snakes contained high levels of lead, cadmium and mercury after researchers fed them contaminated mice.

In addition, seasnakes could also absorb chemicals from the water through their skins. All these contaminants, within their bodies and outside in the environment, accumulate in the skins just as they collect in pigeons’ feathers.

Shine and his colleagues found higher concentrations of trace elements in the shed skins of jet black turtle-headed seasnakes. Of the 13 pollutants they detected, five – cobalt, manganese, nickel, lead and zinc – were especially concentrated at levels that could cause health problems in mammals and birds. Even in banded ones, the black sections of the sheds had more contaminants than the white sections. Becoming black appeared to be a way of excreting pollutants.

Black snakes shed their skins oftener than pale ones because algal spores tend to accumulate on dark surfaces. If they didn’t slip off their skins, growing algae create drag, slowing down the snakes. In toxic waters, this frequent sloughing would not only get rid of algal spores but also the adhering contaminants.

Such adaptation to human activity can be rapid. In peppered moths, the mutation for black colour occurred as recently as 1819, nearly three decades before the first record. In turtle-heads, the researchers suspect the mutation for melanism is unique to the species. Seakraits (Laticauda sp.) are similarly banded, but the mutation to make jet black individuals may not have occurred yet even though Goiran and Shine found pollutants in the dark-ringed sections of their sloughs.

This is the first and only evidence of a snake changing its colour in response to industrial contamination.

Since pollution would affect both genders, why are males overwhelmingly melanistic?

“The sex bias isn’t very strong, and I haven’t looked at the data recently – the difference may even have disappeared,” says Shine. “But if it’s real, it might reflect the fact that male and female turtle-heads feed in different seasons, on the eggs of different types of fishes. One type may well have more pollutants than another.”

Despite the number of black seasnakes they observed, the Shine family didn’t catch a black-coloured juvenile. All the youngsters they caught were brightly banded, but Shine doesn’t think they change colour in their lifetime.

Since black turtle-heads are better at coping with pollution, it’s possible they may outnumber the banded ones just as dark peppered moths replaced light ones. However, this blackening of a species may not be irreversible. With stricter laws to check pollution in Britain, the light-coloured peppered moths are returning. Turtle-heads probably could retain their vivid banded forms off the New Caledonian shore if contaminants didn’t spill into the sea.

How to stay safe in the great outdoors

Summer trips to the great outdoors are rewarding but come with some specific challenges. How much you know about some of the dangers you might face? NYT has a Q&A with some useful tips: 

If you encounter a bear at a distance while hiking:
Slowly back away. If you encounter a bear at a distance, the National Park Services says to slowly back away. If you surprise one, do not run, as it may trigger a chase response from the animal.

If a bear charges toward you:
Stand your ground and use bear spray when the animal is 30 to 60 feet away. If a bear charges toward you, stand your ground and begin spraying when it is 30 to 60 feet away. Rangers at Yellowstone National Park recommend hiking with bear spray, a pepper spray that inhibits a bear’s ability to see, smell or breathe. Only when a bear makes contact should you play dead to show that you are not a threat. Fighting back during an attack only increases the danger of injury.

The following will help keep bears away from your campsite:
Properly storing all food and garbage. The American Bear Association recommends securing all scented items by hanging them at least 10 feet off the ground and five feet from a tree, as well as storing all food and garbage in sealed bags or airtight canisters.

If you encounter a mountain lion:
Wave your arms and make loud noises. According to the Mountain Lion Foundation, if you are attacked, do not run, but stand tall and open your coat or raise your arms to look big. Maintain eye contact, slowly wave your arms, speak firmly and throw items at the mountain lion if necessary. Normally, the cat will move on.

The best way to remove a tick from your skin is to:
Use tweezers to grab the tick as close as you can to your skin, then pull straight up and away from the skin. The Center for Disease Control recommends removing the attached tick as soon as you notice it by grasping it with tweezers, as close to the skin as possible, and pulling it straight out. Lymedisease.org says to not squeeze the tick, burn it with a match or cover it with Vaseline. Squeezing the tick’s body could release any toxins into your body.

After removing the tick, you should go to the doctor:
If you develop a red rash of any shape.
If you develop a fever or flulike symptoms. Lymedisease.org says that while a bull’s-eye rash does indicate Lyme disease, not everybody who has been infected gets one. You might develop a different rash or have no rash at all. If you have a rash of any kind or you develop flulike symptoms, WebMD suggests seeking medical assistance.

If you encounter a snake:
Stay calm and keep your distance. The University of Florida Department of Wildlife Ecology and Conservation suggests leaving the snake alone and to not stand between it and bushes or other cover, as snakes will usually try to escape. A snake may also strike when startled, so giving it space is crucial.

If you are bitten by a snake:
Keep your distance from the snake and obtain medical care as soon as possible. WebMD says that any snakebite victim should go to a hospital emergency department unless the snake can be positively identified as nonvenomous by an expert. Even if the snake is nonvenomous, it is a good idea to seek professional wound care; you may need a tetanus booster.

There is more of a chance of dying from a shark attack than:
Thankfully, shark attacks are rare. According to aqua.org, the chance of dying in a shark attack is 1 in 3.7 million.

If a shark attacks you:
Fight back by grabbing its eyes and gills. “The best thing to do is fight back. Grab at the eyes and gills, which are very sensitive. Punching the shark in the nose may help but is difficult to do in the water,” said Andrew P. Nosal of the Scripps Institution of Oceanography.