fungus – BioQuakes

There is a certain fungus that turns ants into zombies, but afterward, they explode. When ants are just walking by minding their own business they step on fungal spores. It attaches to the ant’s body and the fungal cell goes inside of the ant. The fungus feeds from within and increasingly multiples cells and it is called, Ophiocordyceps, mainly living in the tropics. The danger about this fungus is that the ant is unaware of this whole process, it goes about its daily life, searching for food and bringing back to its nest. However, the fungus takes up half of an ant’s body mass. It undergoes a parasitic relationship where the fungus benefits, while the ant is harmed.

Once the fungus is done feeding, the ant will feel a needle-like sensation. What is happening here is that the fungus is pushing on the ant’s muscle cells. And the cell signals also get sent to the ant’s brain, then the ant will climb upwards above its nest. Ophiocordyceps does something very weird where it allows the ants to move upwards to a leaf above ground and then the ant bites down, where it locks its jaw. Then it sends out “sticky threads that glue the corpse to the leaf.” The ant’s head then bursts open, called a “fruiting body”, where it looks like horns projecting from the ant’s heads and the horns disperse more of these fungal spores onto its nest below it leaving behind a trail of spores.

“The ants are walking over a minefield,” said David Hughes, an expert on Ophiocordyceps at Pennsylvania State University.

Hornlike antlers that come out of the ant’s head

There is still so much that is unknown about Ophiocordyceps because scientists don’t even know what kind of chemical gets into the ant’s brain causing it to climb. There are ants that age back to 48 million years old gripped onto leaves. Scientists thought there was one species that zombified ants but it turns out there are at least 28 different fungal species that attack other insects as well. Dr. Araújo drew out a family tree to see what was infected by Ophiocordyceps. It became known that all Ophiocordyceps species come from a common ancestor, first infecting beetles larvae, not hemipteran.

The beetles that are affected by the larvae live in eroding logs.

“They’re mostly solitary creatures, with a very different life history,” compared to ants, she said.

It can now be inferred that possibly millions of years ago when this was happening to beetles, ants picked up the fungus if they were living in the same logs. Thus a constant cycle and more spreading of fungal spores. Even though natural selection favored keeping the ant’s host healthy and away from parasites, Ophiocordyceps had to find a way to make the ant leave the nest, not far enough from its environment, but just in the right place to send out the spore to infect whatever other ants were living around it.

Because this behavior is so unordinary it is not possible that only one gene is responsible for all of this. They keep finding new species. Dr. Hughes and Dr. Araújo are still researching to find that there are hundreds of other species of Ophiocordyceps that are yet to be discovered.

60 Million Year Old Farmers

By holmesosapiens

On October 31, 2018

In Student Post

Microbial ecologist Cameron Currie of the University of Wisconsin-Madison has made an intriguing discovery about the lives of some South American leaf-cutter ants. He found that long before humans cultivated fruits and vegetables for food ancient leaf cutter ants where cultivating fungus. The ants farm the fungus as a food source, but there are pathogenic bacteria that can kill the fungus. To thwart these malicious bacteria, the ants have formed a symbiotic relationship with a different bacteria known as actinobacteria. These actinobacteria fight off the pathogenic bacteria and protect the fungus.

Leaf Cutter Ant

But how could we possibly know if fungal-farming ants existed millions of years ago?

Ant Trapped In Amber

Well, I am glad you asked. Curries research focused on a 20-million-year-old sample of amber that had a few of these green-thumbed ants trapped inside. The ants had specialized pockets in their heads called crypts where the ants store these actinobacteria. These leaf cutter ants are walking pharmaceutical factories.

It is intriguing that some of the smallest insects on the planet where farming and cultivating food millions of years before we even thought of it. Not only that, but they have been using anti-biotics for millions of years whereas humans have only started using them 60 or 70 years ago.

What lessons do you think humans today can take away from these ants? Could they be the key to our anti-biotic overuse crisis?

White-Nose Syndrome Threatening Brown Bat Species

By sgagocytosis

On January 16, 2015

In Student Post

In 2006, hibernating bats in upstate New York were identified with white-nose syndrome , a disease that produces a white fungal growth around the wings, mouth and nose of bats. The disease is a huge problem for North American bats, with it killing at least 6 million brown bats and the disease now spreading from New York to Mississippi and Canada. The disease may even threaten the entire bat species and disrupt the ecosystem. Scientific researchers have been studying WNS for over a decade and only recently have they developed a reason for its lethal effect on the North American bat population.

Researchers from the US Geological Survey and the University of Wisconsin learned that the fungus Pseudogymnoascus destructans kills brown bats by “increasing the amount of energy they use during hibernation”. When bats are hibernating during the winter, they must carefully save up their energy to survive without eating until the winter ends. The fungus drains bats of their energy and forces them to wake early and either starve or freeze to death. The study done by USGS measured how much fat was burned and at what rate during hibernation between non-infected and infected bats. Dr. Michelle Verant, a USGS National Wildlife Health Center scientist, found that bats infected with WNS used twice as much energy as the healthy bats during hibernation and had “potentially life-threatening physiologic imbalances that could inhibit normal body functions”.

The immune system of bats is very tolerant of pathogens and diseases that can be lethal to humans, like ebola and even some cancer cells. Bats are immune to many viruses and rarely show signs of disease so the visible white growth on the bats poses a huge threat to the ecosystem. Dr. David Blehert worked with Dr. Verant at the USGS National Wildlife Health Center and the WNS is scary because “here we have an animal that can survive some of the scariest viruses we know, and it’s undone by a common soil fungus.”

Brown Long-eared Bat

Main Article:

http://www.science20.com/news_articles/winter_hibernation_energy_drain_how_whitenose_syndrome_kills_bats-151997

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: fungus

Did ants originate from zombies? This fungus will give you the answers.

60 Million Year Old Farmers

White-Nose Syndrome Threatening Brown Bat Species

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