Something Fishy About These Networks

A couple weeks ago, I presented this poster at our final science research colloquium. It went well. I cracked a few hilarious jokes here and there, people laughed, our poster looked super cool and had a really nice color scheme…anyway, the issue wasn’t getting people to come by. It was mastering explaining the complex networks—that I’m taking many blog posts to write about—in 2-3 minutes. It was especially nervewracking when the president of the entire American Museum of Natural History expressed interest in our tiny fish. The whole process of preparing to present my research helped me realize that while it’s impressive to have the knowledge to write a scientific paper, it’s even more impressive to be able to convey your work to family, friends, and others not directly connected to the scientific community. While in the process of making our poster, I often wanted to show off my new scientific vocabulary. My mentor encouraged me to consider the intended audience and what would be most understandable to them. 

The importance of this suggestion struck me only later when I was walking around and glancing at others’ posters at the colloquium—I realized how much of a difference it made just to be able to understand the title of a complex project’s poster; I felt so much more comfortable going up and asking about the research. I type this blog by myself behind a computer screen and have more time to shape my writing to ensure that it is clear  to my readers (whether that be my Grandma, my friends, or some poor guy who just wanted a popsicle recipe). However, this presentation taught me that answering scientific questions without being confusing is a lot more difficult when you’re actively communicating with someone, and it’s something I want to continue to practice. 

Anyway, I’m getting a bit theoretical. Back to the fish! Even once I gave the audience a little crash course on reading haplotype networks, the tricky part still remained: interpreting them and drawing conclusions. To start, I’ll bring you back to the original question that this research was trying to answer: Is the genetic diversity in Congolese Killifish affected by paleoclimatic events? A lot of my blog posts on this project have been centered on the molecular lab work we performed (because it’s sort of awesome and I love writing about it). The lab work revealed the exact genetic variation between populations of these six species. Ok, great, so some species varied more than others…but here came the question I was asked over and over again when presenting. WHY? 

Well, there’s no one answer. It’s like if you asked me why I’m part Indian, part German, part French, part English, and part Irish. To be completely clear with you, it gets a little murky past the first few. But my point is, so many different events (migrations, chance encounters, etc.) resulted in my being the way that I am. The same thing can be said for the genetic makeup of these fish. Like our question asked, yes, it is in part due to paleoclimatic events. But it’s also due to other factors, such as how long these fish have been in the Congo rainforest and how their ecological niches have affected their ability to move. So let’s DIVE (haha..like fish..) into the specifics of the haplotype networks!

Ultimately, we found three distinct patterns within the networks that were largely dependent on the environment these fish were living in. 

1. Rainforest Dwelling Species

2. River Dwelling Species with High Genetic Diversity

3. River Dwelling Species with Low Genetic Diversity

In the next few blog posts, I’ll discuss what these patterns revealed about the nature of these fish and how we can use past events to predict future changes in genetic diversity. Happy reading!