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When it comes to symbiosis, two is company; three is a crowd. It’s the same thing in nature.

When it comes to symbiosis, two is company; three is a crowd. It’s the same thing in nature. The symbiosis between a microbe which provides nutrients and a fungus, which provides a place to live have been a textbook example for the past 150 years. However, it is not the complete story.

Now, a third element was added to the symbiosis. Recent studies have revealed that this third member of the symbiosis is also a fungus, previously unknown to scientists. The fungus has been found on all continents, and its presence shows it is encountered everywhere. It has been part of the symbiosis from the start of this partnership’s evolution.

Catharine Aime, from Purdue University, who co-authored the study believes that textbooks will have to be rewritten.

Toby Spribille, the leader of the novel analysis, has been passionate about lichens for the better part of his life. These lichens are very hard to grow in laboratory conditions. Scientists had no idea how to bring about the symbiosis which happens in nature. So far, experiments on lichens have been few and the results – unsatisfying.

As science advanced, so did metagenomics – DNA extracting tools – have. This type of approach sparked Spribille’s imagination. He found out that a type of lichen encountered in Canada and throughout the western part of the United States called Bryoria had a strong cultural bond with old local tribes. Amerindians used them to get through the winter. They would wash Bryoria of other substances found on their surface so that they wouldn’t get sick.

Part of these substances is a toxic acid, called vulpinic acid. There are two types of Bryoria, one which produces vulpinic acid and is toxic, and the other one which does not.

Laboratory analyses confirmed Spribille’s theories. Now we know a third fungus is a partner in the symbiosis. He used metagenomics, a new scientific method of DNA sequencing, to confirm his findings.

The new fungus is now being studied more intensively. The vulpinic acid is sure to play a role in this symbiosis; scientists are now trying to figure out which. For now, experts believe it produces metabolites, but further research is needed.

Spiribille is amazed at how complex this symbiosis is. He finds a lot of his inspiration in nature.

Image Source – Wikipedia

Hummingbirds are nature’s versatile fliers.

Hummingbirds are nature’s versatile fliers. They swoosh faster than 50 kilometers per hour and quickly stop when navigating through dense vegetation. Recently, scientists discovered that the hummingbird vision is adapted to high-speed flight.

Research has revealed that these small birds take in visual information completely differently from other species, probably because they have to balance out their acrobatics.

Birds are quicker than insects in flight, so the danger of a collision increases. Roslyn Dakin, a Ph.D. fellow and study leader, wanted to know what helps hummingbirds to avoid collisions. Research also had to point out how big is the difference between them and insects, when establishing a clear path.

Researchers put hummingbirds in a special tunnel, where they projected nature patterns on the walls. This helped them realize how the birds steer clear to avoid collisions in flight. Scientists installed cameras to track the movements of hummingbirds. They flew in a 5.5-meter long tunnel.

The experiment worked by taking advantage of the hummingbirds’ appetite for sugar. So a feeder containing sugar was placed on one side of the tunnel and water was put on the other side. This made the tiny birds fly back and forth all day long. Scientists were this way able to test many different visual stimuli.

To date, we don’t know too many things about birds’ orientation in high-speed flight. We only know that bees process distance similarly to humans. For example, a bird processes distance by how quickly the object passes through their field of vision, just like we do, when driving on a road. We see poles closer to the street and buildings in the distance. Timing tells us how far away they are from us.

Hummingbirds did not react to bee-mode simulations. But they did react to fly-like simulation. Objects getting bigger or smaller in the distance tell birds if they move further away or closer to the object.

In the end, scientists found that hummingbirds have the same technique as flies. This is known as “image velocity” and it helps both species to know their altitude and distance. Humming birds are even able to fly backward. This is done with about the same amount of energy and oxygen as flying forward.

Image Source – Wikipedia

Three Is A Crowd

Hummingbird Vision Is Adapted To High-Speed Flight

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