Within two days of Josh Penalba submitting his PhD, the Biology graduate started working in a lab at the Ludwig Maximilian University of Munich.

We caught up with Josh (who studied a Doctor of Philosophy, via the ANU Research School of Biology) via correspondence, to ask him about his journey to Canberra and beyond.

Josh, congratulations on graduating from ANU with your PhD. We understand you're from the US? Tell us where you're from and what led you to study at ANU?

I grew up in California and pretty much did all of my studies there. When I was an undergraduate at UC Berkeley, I had met who would later become my PhD supervisor at ANU, Professor Craig Moritz.

I was volunteering at the Museum of Vertebrate Zoology, where he was the director at the time. Not too long after we had met, I heard that he was moving to ANU to start his ARC Laureate Fellowship and the Centre for Biodiversity Analysis. I also knew he would be looking for PhD students to start with him there.

So two years before I had finished my undergraduate studies, I expressed to Craig my interest in working in his lab as a PhD student at ANU. It was too early at the time to be certain that any of it would work out, but I spent the next couple of years preparing myself for the PhD position and keeping in constant contact with Craig as he slowly transitioned from California to Canberra. A few months before I graduated, Craig graciously offered me the PhD position and I moved to Canberra later that year. 

What did you study at ANU?

My thesis focused on trying to understand how two populations of birds eventually become two species, the process we call "speciation." The rapid advancement in technology in the last decade has allowed researchers to easily obtain genomic data, the entire genetic blueprint of an organism. It complicated what we thought we already knew but definitely made it that much more interesting.

One of the scenarios that lead to populations becoming different is when they become geographically separated for a period of time. Where it gets interesting is when they come back together, because it tests whether individuals in these populations still recognize each other as potential mates or not. Depending on how far along the speciation process two populations are would shape how much genetic exchange might happen when they come back together.

For my thesis, I took an approach where I compared populations at different stages of speciation and used genomics as a tool to infer how differentiated these populations truly are and what that translates to when it comes to genetic exchange between them.

We were told that within two days of submitting your PhD, you started a job in Germany - that's a pretty amazing accomplishment! Can you tell us about this?

This lab I now work at in Munich is a group I'd always been keen to work with as they have been pretty prolific in my field of interest. They had advertised for a postdoc position a year before I was meant to submit my PhD. I expressed interest in the position anyway but they were looking for someone who can start sooner.

Fast forward 6 months, I went to Italy for a conference and stayed in Sweden for a few weeks to visit and work at a lab. I used my time in Europe as an opportunity to scope out potential postdoc opportunities. I figured I'd take the opportunity to also visit the lab in Munich anyway while I was still looking for opportunities. It turns out that they had not found anyone for the position I initially applied for and after coming over, presenting my research, and interacting with the lab, I was offered the position to start immediately after I submitted my PhD thesis.

What was it like to move your life from Canberra to Munich, within such a short space in time?

Dealing with moving your life across the world while trying to finish a thesis was admittedly incredibly stressful. It was a whirlwind of events and emotions. If it wasn't for my PhD family in the division of Ecology & Evolution, I don't know how I could have made it through everything in one piece. All my good friends in the department were incredibly helpful and supportive every step of the way. My time in ANU and E&E was special not just in the academic side but especially in the social side of things. Leaving good friends so quickly after going through something as big as finishing a thesis was like ripping an emotional bandaid. After all that, landing in Munich was definitely quite disorienting. Everything was new, including the language. It took some time to reorient myself but when I did, the excitement of all the new prospects and adventures propelled me forward. 

Back onto what you're been studying at ANU now - can you talk about genome divergence and speciation. What interests you most about species development and how they are impacted by genomes?

What I find exciting about studying speciation is that it is one of the foundations laid out by Darwin in the early days of evolutionary theory.

Although speciation itself is an older field, speciation genomics is quite young and full of opportunities to test standing theories in a larger scale and potentially formulate new theories with this new perspective.

The genome doesn't only shape how an organism may look or function in present day but it can also be seen as a history book with signals left from the processes of the past.

I guess one could say that the genome is laden with mystery as different processes could leave similar signals and it's our job to disentangle that and create a better reconstruction of the past. 

Why is it important to know about species and their genomic variations?

It is important to know that when it comes to appreciating the animals and nature around us, what we see with our eyes barely scratches the surface. Things that may look strikingly different may actually be practically indistinguishable when we look at their genomes and conversely things that may look identical to us may actually have a long history of differentiation to the point they recognize each other as completely different entities or species.

Speciation is not only a historical process but one that is happening now and will continue well into the future. If we can mine the genomes for information as to how the biodiversity around us have formed and is forming we may also be able to understand how it may continue to form and how our actions can create ripples in this multimillion-year process.

Do you have a long-term goal concerning your research, and where you see yourself in the future?

I'm definitely quite excited about continuing what I started during my PhD at ANU. I am still continuing to develop this study system of birds in Queensland so that it opens up even more avenues for new research questions in speciation genomics and evolution.

If all goes according to plan, my goal for the future is to establish my own lab studying speciation genomics with the Australian birds as my pet study system. I'd also definitely broaden myself by asking similar or related questions in other organisms and collaborating with various researchers in other fields. I am really excited about the future prospect of mentoring my own students and early career researchers to help develop their research ideas that will push the boundaries of evolutionary biology.

What advice would you have for any students considering studying speciation genomics?

Firstly, speciation genomics is a rapidly evolving field. My advice would be to keep on top of the scientific literature, attend conferences, and even pay attention to science twitter for the most up-to-date conversations. What might be cutting-edge or novel one week can be completely changed up the next.

Secondly, I advise not to forget about the life history of the organism and the history of the geographic region they reside in. It's easy to get caught up with the massive amount of data that stepping back and looking at the bigger picture can often provide additional valuable insight. 

Thanks Josh, we wish you all the very best for your future and we hope that you will keep in touch with ANU.