Sunscreen, Coral and You

World's Deadliest Animal

What’s the world’s most dangerous animal? Sharks? Nope, they bite only 70 people a year, with just six fatalities. Poisonous snakes? They kill about 50,000. But far and away the most dangerous is the mosquito. It kills a million people a year, and sickens 250 million more! But we may be able to stop it, with an even tinier creature. There are 3,000 species of mosquito. Different ones can carry malaria, West Nile virus, Zika, yellow fever, dengue, Japanese encephalitis, and more. They don’t cause these diseases, but instead bite an infected person, then pass it to others. Some of these diseases, like malaria, have medicines to prevent and treat them. Others like dengue, don’t. But scientists may have found a novel solution – infecting the mosquitoes themselves, with bacteria called Wolbachia. Wolbachia exist symbiotically in about 50% of insect species. When introduced to mosquito populations, they consume essential molecules within the insect, like cholesterol -- the same thing that Zika and dengue rely on. This means those diseases can’t survive within the mosquito and can’t be transferred to more humans. Wolbachia don’t kill the mosquitoes, and are found to be harmless to humans and other creatures that depend on mosquitoes for food, like birds and bats. A microbiological treatment for a global disease problem.

Fibonacci Sequence

Amazingly, the structure of most living things, and many other things as well, conforms to one sequence of numbers. It was described in the 1200s by Italian mathematician Leonardo Pisano, also called Fibonacci, working from earlier Indian ideas. The Fibonacci Sequence is 1, 1, 2, 3, 5, 8, 13 and onward – where the first two numbers, one and one, add up the next number, two. The next two numbers, one and two, add up to the next number, three. And so on. Most flowers have three, five, eight or thirteen petals. Spirals found in nature – seeds in a flowerhead, snail shells, even hurricane clouds – expand outward according to the sequence. Scientists looked at 12,000 spirals in different species and found that 90% adhered to the Fibonacci Sequence. But we’re not sure why. The pattern must confer some kind of structural advantage, enough that it continues to persist in newly formed species. Human designers often use the Fibonacci Sequence intentionally when designing art or architecture. Or unintentionally, by mimicking the geometries of nature. You can see it the next time you pick up a pinecone, eat an artichoke, or look in the mirror. The human body has one head, one torso, two arms, with three segments each, ending in five fingers. Efficient and elegant, the Fibonacci Sequence is the shape of nature.

Sunscreen, Coral and You

You may have seen sunscreens that claim to be “reef safe.” Which may have made you wonder, are sunscreens dangerous to coral? If so, could they be dangerous to me? Sunscreens come in two basic types. Inorganic, which are mineral based, using white zinc or titanium oxides to physically block the sun’s rays. And organic, using oxybenzone or octinoxate to absorb UV rays and turn them into heat. You’d think the organic ones would be healthier for humans. But some studies found they can penetrate the skin, enter the bloodstream, and may interfere with endocrine systems. In corals too, some studies showed that very high concentrations of oxybenzone sunscreen make them eject the symbiotic algae that lives within them. Without the algae to conduct photosynthesis, the corals bleach and may die. While you should always protect yourself from the sun, you may want to avoid sunscreens with oxybenzone or octinoxate. And avoid spray or powder sunscreens as they can be toxic when inhaled. The lowest risk, and most effective sunblock, is to cover up or get out of the sun mid-day. And use mineral-based sunscreens when needed. If you want to protect corals, ironically one of the best things you can do may be to visit and admire—though never touch—them. Your tourist dollars encourage local authorities to protect their reefs from fishing and overuse, and preserve them for future generations—of visitors, and coral.

Mighty Moss

Mosses are small but mighty. We don’t think much about them, since they grow so close to the ground. But there are an estimated 22,000 species of moss, living on every continent including Antarctica, covering 2% of Earth’s surface. That’s the size of Canada! The soil under mosses globally can store 6 billion tons more carbon than bare soil. That’s more than the U.S. emits each year. After lichen, mosses are the second stage in what’s called the ‘primary succession’ – the conversion of a barren environment, like a lava field, into one that can sustain life. With enough water, moss will continue to grow, decay and grow again, forming the basis of soil. And within the moss, other lifeforms begin to grow, like fungi and ferns. But also mites, tardigrades and nematodes. Under a magnifying glass, mosses look like miniature forests. And they’re hardy. One desert species in China can tolerate some of the lowest and highest temperatures on Earth. To test its toughness, scientists exposed the moss to even greater temperature extremes, froze and dehydrated it. The moss rebounded without issue. They even subjected it to radiation that would be lethal to mammals. The moss just grew faster. The idea behind these tests was to see if this particular moss could one day be sent to Mars. One of Earth’s lowliest species just might green the red planet.

Grand Teton National Park

Grand Teton National Park contains North America’s youngest mountain range: the towering “Tetons.” While the range formed by extension along a tectonically simple “normal” fault, the Teton Fault is unique because it has moved nearly 33,000 ft (10 km) in just ten million years. Preserving astounding natural beauty and a human history stretching back at least 11,000 years, the national park was first established in 1929.