In class, you have likely learned about the scientific method.  The scientific method is an incredibly powerful tool that allows us to ask questions and critically evaluate potential explanations for processes that occur in the world around us and even, the world within us.  Sitting in the classroom, it can be hard to picture how the scientific method is applied in universities and government and private industry labs around the world that do scientific research.

 

Before we conduct a study and after we apply the scientific method to address a specific question, the process of doing scientific research includes many additional steps before our findings are available to the public.  While you may be able to conduct a lab in the classroom in single or even a few class periods at your school when scientists test a question it often takes multiple years before it’s available to the public.  Part of this process ensures that published research is sound to reduce the chance that bad information is made available to the public.  A student from Auburn Middle School recently interviewed me about the process.  The transcript of our interview is posted below.

 

Dr. Wendy Hood

 August 19, 2016

 

Interview transcript:

 

Student: Where do you get your ideas for your research projects?

 

Dr. Hood: Most of our ideas come from observing nature, reading about studies 
that other scientists have done, and our own research observations. 

 

Student: Can you give me an example?

 

Dr. Hood: I became very interested in the role that mitochondria play in aging

associated while reading a popular science book with an intriguing title,

Power, Sex, Suicide by Nick Lane.  This was an unusual source of inspiration for us as most of our inspiration comes directly from the published scientific journal articles. At the time, we were in the middle of a long-term study on reproduction in house mice.  In addition to collecting the key data needed for the original study, we thought it would be interesting to also look at how well the mitochondria work in these animals.  So, I contacted my colleague, Dr. Andreas Kavazis, who is also a professor at Auburn University, and I asked if he would be willing to work with us.  He agreed, and we found something really interesting.  Reproduction is thought to speed up the aging process.  So I thought that the mitochondria of mice that had reproduced many times would not work as well as the mitochondria of mice that didn’t breed but were the same age as females that had bred.  Interestingly, the mitochondria of mice that reproduced did not display reduced function.  Instead, we saw a pattern that suggests that the mitochondria may even function better after reproduction.

 

I was puzzled. How could reproduction both reduce longevity and improve how mitochondria work?  Either reproduction doesn’t have a negative impact on mitochondria, or the relationship between reproduction, mitochondria, and aging is more complex than we thought.  We’re working on understanding this in my lab now. Specifically, we’re looking at how mitochondria function changes as individuals get older and how mitochondria function changes as a female mouse has more and more litters of pups.  

 

Student: So you now have your idea, what’s next? 

 

Dr. Hood: We had that interesting finding.  We spent a lot of time reviewing the scientific literature, which are the results of studies published by other scientist.  We asked if published results could explain our findings.  The literature suggested that in some cases reproduction may benefit the body and in some cases it may not.  So I hypothesized that the effect that reproduction has on the body changes as an animal ages.  The next thing I had to do was to find money to support the new project I designed based off of this hypothesis. 

 

The federal government funds many complex and expensive research projects.  These funds are highly competitive and there is a careful vetting process for grants.  A team of scientists’ reviews the proposals that other scientists send in for consideration.  That team helps to decide which proposals get funded.  Only the strongest projects, projects that are well thought out and predicted to make an important contribution to the scientific community, are funded. I’m happy to say we got one of those grants.

 

Student: When you design an experiment, what do you think about?

 

Dr. Hood: I think about a lot of things when I design and experiment – I love designing experiments - its like organizing a surprise party, it requires a lot of creativity and planning and it's exciting to see how it comes out. 

 

When designing an experiment, I think about "what is the best species to study?" We study house mice in many of our studies because they have short lives and lots of babies – two variables that are key to studying reproduction and longevity.  In addition, house mice also put relatively more energy into reproduction for their size than any other mammal.  This should make it easier to determine how mitochondrial function contributes to the impact that reproduction has on longevity.

 

I also ask "what is the best environment to conduct our work in?" Most people study mice in a laboratory setting.  That setting works well for many studies, but we wanted the animals to display a natural level of activity and maintain a natural social environment.  So for many of our experiments, we keep our mice in environments that mimic the conditions of wild mice living in a barn.

 

I think about our experimental, or treatment groups, and our controls.  Deciding what we want to use as controls in our studies can be complicated.  Sometimes, we want to hold all possible variables constant other that the variable we are testing.  For example, many studies on lab mice hold social environment constant by keeping mice alone in a box. Other times, we want our animals exposed to the conditions they naturally live in.  Mice rarely live a solitary existence, so we often keep our mice in groups that mimic the conditions they are found in when they are in the wild.  For our study, we decided not to hold social environment constant, as all the interactions that a mouse experiences during its life could contribute to how long it lives and we want to see how those experiences interact with reproduction. We keep a group of control mice that aren’t allowed to reproduce to compare to our mice that do reproduce. We compare these groups or reproductive and non-reproductive mice and determine how reproduction impacts the mitochondria. Because we want to see how mitochondria change with age, age is our independent variable and our dependent variables are measures of capacity of the mitochondria – things like how much oxygen mitochondria use and how damaged mitochondria accumulate. 

 

We also spend a lot of time thinking about what methods will give us the most accurate and precise measurements so that we can be really confident in our results.

 

Student: Do your studies always come out the way you expect?

 

Dr Hood: Studies don’t always go as we expect. When I described that mitochondria may do better after reproduction – that was totally unexpected.  But, that finding turned out to be a great thing for my lab.  Finding something unexpected has changed the focus of our research - we now work to understand if and how reproduction can benefit mitochondria.  I think my lab will be working on this problem for many years.

 

Student: After you are done with your experiment, how do you let people know about

your results?

 

Dr. Hood: The first thing we do is present our research as a talk or poster to other

scientists at scientific meetings.  This gives us an opportunity to get feedback on our

ideas.  This is incredibly valuable, and it's a lot of fun to discuss the work we are excited

about with other people.  We want to hear if people agree with how we interpreted our

results or if they disagree.  It’s not a bad if they disagree – we want to consider all

angles and makes sure our interpretations are solid.  Next, we write up our results for

publication.  In this process, several scientists review our paper and make sure the

science is free from errors, logical, and reviewers make sure we aren’t making claims

that aren't supported.  This process should give the public confidence that work that is

published is sound.  Importantly, scientists have learned to always be skeptical of new

findings until they see that other investigators have comparable results.  Once we see

pattern over and over again, we gain confidence that the pattern observed is a real and

common in nature.

 

Here is the link to the published paper from the study I described above so you can see how we disseminate information. Please feel free to read it!