Dr. Rachel Welicky has been telling all of us to thank parasites for the crucial role these creatures play in our world. Now Neumann University's Biology professor is reaching an even broader audience thanks to an article published in The New York Times about her research on this hard-to-love species.

The article, "You May Miss These Parasites When They're Gone," was published on January 9, 2023, by New York Times writer Rachel Nuwer. The gist of the article is "warming temperatures in one part of the world seem to have driven down the parasite population, suggesting another unexpected way that climate change harms ecosystems."

"We were not sure if it would be in The New York Times. We were happily surprised," Welicky said.

Welicky worked with Dr. Chelsea Wood, a parasite ecologist at the University of Washington who authored the study. The paper was titled "A reconstruction of parasite burden reveals one century of climate-associated parasite decline." It first appeared in the Proceedings of the National Academy of Sciences, a peer-reviewed scientific journal. Welicky calls the study a "serious labor of love."

"We opened up 699 fish, and we dissected every single one. They came from all different times, and the earliest was pre-1900s," she said.

The three-year study extracted data on parasites from marine fish specimens collected from natural history collections for eight fish species between 1880 and 2019. The team analyzed 85 parasitic species and concluded that global warming is causing the parasite population to decrease.

However, this was not a foregone conclusion when the study began.

"I felt that there would be some trend, but I was not truly sure which direction the trend would go in and whether parasites would be on the rise or the decline simply because there's enough biological mechanisms that could have made either plausible," Welicky explained.  

Welicky has been studying these multi-faceted creatures for more than ten years. She describes parasites as intensely complex and interacting differently with various host organisms, including fish and people. Parasites have massive effects on the host, which can be easily seen or undetectable.

"There's always this element of surprise when studying them since there are hundreds of thousands of different types of parasites. Not all are bad and scary, but it's an endless supply of information, and I just love learning," she noted.

Read the full article