Agriculture
Growing Healthier Tomato Plants
Earth-Friendly Fabrics
Getting the dirt on carbon
Amphibians
Frogs and Toads
Bullfrogs
Toads
Animals
Helping the Cause of Macaws
G-Tunes with a Message
Stunts for High-Diving Ants
Behavior
Brainy bees know two from three
Chimpanzee Hunting Tools
Swedish Rhapsody
Birds
Flightless Birds
Storks
Mockingbirds
Chemistry and Materials
Revving Up Green Machines
The memory of a material
A Butterfly's Electric Glow
Computers
Toxic Dirt + Avian Flu = Science Fair Success
Nonstop Robot
Graphene's superstrength
Dinosaurs and Fossils
Tiny Pterodactyl
Downsized Dinosaurs
Fossil Forests
E Learning Jamaica
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Results of GSAT are in schools this week
2014 GSAT Results for Jamaican Kids
Earth
Petrified Lightning
A Dire Shortage of Water
Recipe for a Hurricane
Environment
Bald Eagles Forever
Flu river
Forests as a Tsunami Shield
Finding the Past
Prehistoric Trips to the Dentist
A Long Haul
A Long Trek to Asia
Fish
Sharks
Electric Ray
Carp
Food and Nutrition
The mercury in that tuna
In Search of the Perfect French Fry
Allergies: From Bee Stings to Peanuts
GSAT English Rules
Who vs. That vs. Which
Capitalization Rules
Whoever vs. Whomever
GSAT Exam Preparation Jamaica
GSAT Exam Preparation
Preparing for the GSAT Exam
2014 GSAT Results for Jamaican Kids
GSAT Exams Jamaica Scholarships
GSAT stars reap scholarship glory
42,000 students will sit for the GSAT Exam in two weeks
Access denied - Disabled boy aces GSAT
GSAT Mathematics
Math is a real brain bender
10 Common Mistakes When Preparing for the GSAT Math Test
It's a Math World for Animals
Human Body
Running with Sneaker Science
Hey batter, wake up!
Fighting Off Micro-Invader Epidemics
Invertebrates
Spiders
Sponges
Black Widow spiders
Mammals
Weasels
Sheep
Dalmatians
Parents
What Not to Say to Emerging Readers
The Surprising Meaning and Benefits of Nursery Rhymes
Expert report highlights the importance to parents of reading to children!
Physics
Echoes of a Stretched Egg
Einstein's Skateboard
Gaining a Swift Lift
Plants
Fastest Plant on Earth
Hungry bug seeks hot meal
Flower family knows its roots
Reptiles
Crocodiles
Chameleons
Caimans
Space and Astronomy
Witnessing a Rare Venus Eclipse
Zooming In on the Wild Sun
Asteroid Lost and Found
Technology and Engineering
Slip Sliming Away
A Light Delay
Supersuits for Superheroes
The Parts of Speech
Problems with Prepositions
Pronouns
What is a Verb?
Transportation
Reach for the Sky
Where rivers run uphill
How to Fly Like a Bat
Weather
Antarctica warms, which threatens penguins
Arctic Melt
Catching Some Rays
Add your Article

When Fungi and Algae Marry

Lichens (li' kenz) are easy to ignore. They can be microscopically small. They don't move. And they often blend into the background. You might not even recognize one if you were staring right at it. Chances are, though, you've come face-to-face with plenty of these crusty, leafy, or shrubby growths. Lichens live on rocks, branches, houses, even metal street signs. You can find these often colorful organisms almost everywhere—from deserts to rainforests, Antarctica to Africa. They've survived trips to outer space, and some scientists suspect there might even be lichens on Mars. "If you go into your backyard, you will definitely find a lichen somewhere," says Imke Schmitt, a lichen researcher—called a lichenologist—at the University of Minnesota, Twin Cities. What you probably don't realize is that a lichen is more than a single thing. It is a thriving relationship between two different types of living organisms: a fungus and an alga. Neither of these organisms is a plant, so the lichen isn't a plant either. Through photosynthesis, the alga harvests the sun's energy to make food for the fungus, which provides a place for the alga to live. But the relationship is lopsided, Schmitt says, with algae caged like prisoners—even slaves—inside their fungal hosts. Around the world, scientists have identified tens of thousands of types of lichens. At least as many probably still await discovery, says Thorsten Lumbsch, a lichenologist at the Field Museum in Chicago. "Even in North America, there is a huge lack of knowledge" about lichen diversity and biology, Lumbsch says. "There's a lot still to discover." As lichenologists continue to find new species of lichens, they are also working to understand how various species are related to one another. By putting together a lichen family tree, they hope to understand why so many different types of lichens have evolved in so many places around the world. Most research involves attempts to understand basic facts about the organisms and their interrelationships. But researchers are also teaming up with lichens to monitor the health of the environment, among other applications. Tough work Studying lichens is rarely easy. Most species depend on very specific conditions, and scientists can rarely get them to grow in laboratories. This provides lichenologists a great excuse to travel around the world, scouting new specimens and insights. Lumbsch, for one, makes several trips to Australia and South America each year. In the field, he searches for a group of crusty lichens that tends to be quite tiny—usually less than a few millimeters long. Finding samples takes patience and a trained eye. "You have to look very closely," Lumbsch says. "Usually, I know which species I'm interested in and which habitats they grow in. So, I go there and crawl on my knees on the forest floor with a hand lens." Spotting lichens is challenging enough. Identifying them is even harder. Many species look exactly alike, even when they are only distant cousins. Closely related species, meanwhile, can live in totally different environments, or on opposite ends of the Earth. (One species, for example, is found only near both poles.) When they're done collecting samples, lichenologists bring their catch back to the lab. Under a microscope, the researchers classify samples by structure and color. Then, they grind specimens into a powder, from which they extract genetic material. These DNA molecules, which appear in all cells, make up genes, which determine how organisms look and work. The more closely related two organisms are, the more similar their DNA will be. Comparing DNA from different species, then, can give scientists an idea of when each group split off from a common ancestor. Researchers use this information to build lichen family trees that depict kinship between species. "Once we have these trees, we can ask a lot of interesting questions," Schmitt says. For example, family trees can help explain what the first lichens looked like, how they have evolved over time, and how far any given species has moved around the globe. Such insights should provide a window into our planet's distant past. Some researchers think that lichens were the first organisms to live on land, long before plants evolved to do so. "[Lichens] have an extremely long history," Schmitt says. "This is what we are trying to uncover by building family trees." The work is slow going, she adds. "But we are beginning to see a picture emerging." Environmental police Despite their reputation as scientific curiosities, lichens have a practical side. Throughout history, people have used different species to make dyes for fabrics, poisons for arrowheads, and "green"-smelling scents for perfumes. Birds use lichens to make nests. Reindeer and other animals, including some people, eat them. (Don't try this at home—some species taste awful!) In modern times, scientists have found a new role for these growths: as environmental watchdogs. Although lichens can live in some of the harshest environments on Earth, Schmitt notes that they "are very sensitive to any kind of change that humans put on the environment." Studies show that some species quickly disappear when exposed to air pollution. These sensitive types also suffer from habitat loss due to logging, construction, or other environmental disturbances. The presence of lichens in an ecosystem, then, generally signals that the air is clear and the environment healthy. Their disappearance, on the other hand, can be a warning sign. Lichens are good monitors of air quality. In fact, studies have shown higher rates of lung cancer in people who live in areas where sensitive lichens have died off. As a result, Lumbsch says, some European cities require developers to confirm the presence of sensitive lichens as a sign of habitable air quality before building new homes. Where lichens reside, city planners can feel confident that homeowners will have good air to breathe. Among other projects, Lumbsch and his colleagues are looking at the effects of climate changes on lichen populations. Some day, he says, lichens might add service as global-warming sentinels to their list of accomplishments. Lichens have long been overlooked. Chat with a lichenologist, though, and you'll find plenty about these underappreciated growths to like, if not love!

When Fungi and Algae Marry
When Fungi and Algae Marry








Designed and Powered by HBJamaica.com™