Student Research Spotlight - Maridel Fredericksen

Posted: May 8, 2015

This is the 6th of thirteen short news articles written by students, during the professional development class, about each other's research.

Brain washed
by Maria Mazin

Someone or something has taken over the ants! They show strange behaviour, wander around with no direction, climb onto a twig and die. Oh yes, and let’s not forget the giant stalk bursting out of their neck the end. Turns out the puppet master behind these walking dead is actually a fungus.

Maridel Fredericksen, a Master's student in Entomology at Penn State is currently studying the fungus responsible what is called behavioural manipulation. Using new and advanced microscopic techniques, Maridel gets interior snapshots of different body parts of an infected ant. Then, with computer programs, she puts the images together to construct a 3D model of the ant, where she can look at the fungus inside its body from different angles.

“We don’t have much information on how this fungus develops over the course of infection, where it is spreading and what tissues it is affecting”, says Maridel. “With these new techniques, we are able to look inside a manipulated ant at a level of detail that no one has ever seen before. We can see how the fungal cells interact with each other and with the ant muscle cells. And the 3D models give us a better sense of how all the cells are arranged in space and in relation to each other. By studying all this, we can start to understand how the fungus is manipulating the ant’s behaviour”.

Fredericksen’s results will help pinpoint where and when the fungus is acting to control the ant, which in the future can lead to which fungal chemicals are important in behavioural manipulation. Also, her studies on abnormal behaviour contribute to a better understanding of how normal behaviour is generated. This is similar to how neuroscientists study people with brain damage to figure out how a healthy brain works. She literally shines lasers at the ants' brains, so she can compare an infected brain to one that's healthy.
Although unravelling the master scheme of behavioural manipulation takes a lot of work, Maridel will continue to get up-close and personal with this fungal puppet master, even if her research project is a true brain cracker.