The Lessons Lake Tahoe Taught Me

It has been over 6 months since I swam the length of Lake Tahoe and I thought I would post something about my swim long ago.  There are two questions that people ask me about this marathon swim.  The first is "why would you want to do that?"  The truth is, that's not an easy question to answer.  One answer is simply, because I think I can.  If I'm truthful though, I also had an expectation that the swim would change me in some radical way or that I would have some big revelation about the meaning of my life.  I thought I would be broken down until I found some core element of myself.  Immediately after the swim I was so grateful, thrilled amazed that I had actually swum all that way, but it also felt strangely anticlimactic.  I had done what I had set out to do and now it was over.  I went back to work the next day and life continued.  As time has passed however, I have come to realize and appreciate the ways that training for and completing this swim has changed me.

The second question people ask me is "what do you think about all that time?"  The answer to this question is both simple and complex.  The short answer is "swimming."  I know that sounds like a smartass answer, but it's true.  While I'm swimming I think about every stroke.  I think about where I'm placing my hands in the water.  I think about breathing.  I think about keeping position with my support kayak.  There were also a few other things running through my head during my swim.  About a week before, a good friend of mine told me "you should think of that time swimming as a gift."  She was right.  Every moment of that swim was a gift.  It was gift to be in the middle of that beautiful lake in the middle of the night.  How many chances are there in life to do something like that?  The biggest gift of all was the time and energy that other people gave to me so that I could have this experience.  I had two friends who kayaked for me through the night giving me food and encouragement and two pilots who I barely knew at the time who guided me safely across.  The fact that all of those people were out for me was overwhelming.  I thought about the fact that being in that water was a gift and a privilege. At about 4 in the morning, a lullaby that my dad used to sing to me popped into my head.  I knew that dawn was coming at some point and I was looking forward to it, but it seemed to be taking forever.  The chorus of the song goes "Oh my Joanie don't you know that the stars are swinging slow and the seas are rolling easy as they did so long ago.  If I had a thing to give you, I would tell you one more time that the world is always turning toward the morning."  The idea of timelessness of nature and inevitability of the passage of time really spoke to me in those moments.  No matter what happened that night in the lake, the sun would rise in the morning. When daylight finally arrived and I could see where I was in the lake I thought about what my friend and training partner told me: "just swim until you run out of water."  What he meant was, don't look for the finish.  It doesn't matter how long you've been swimming or how far you have to go.  You're going to swim until you finish so just keep swimming.  I'm going to admit that I wasn't entirely successful at not looking at the finish, but it never looked any closer until I was right on top of it.  So I put my head down, remembered this advice and repeated it to myself as a mantra "just swim until you run out of water, just swim until you run out of water."  Those times when I was truly caught up in only the present: the sounds of my breathing and splash of my hands entering the water, the feel of the water on my skin and the sight of the stars above, were true bliss.

These months later, I feel a quiet strength and confidence within myself.  The simple, subtle, obvious lesson that I learned is that every moment in time, whether it's amazing, tragic, boring, painful or joyful will pass.  Nothing we experience will last forever.  All we can ever do is to experience and accept each and every moment for what it is.  Almost exactly 1 year after swimming the length of Tahoe I expect to give birth to a baby boy.  I hope that as I embark on this new adventure I can remember to accept each moment as the gift that it is.

Adventures in Scientific Teaching: Flying by the Seat of My Pants

Last week I found myself in the classroom without my prepared powerpoint lecture.  I won't go into the gory details.  Let's just say that it involved an early morning fuzzy headed brain, lost keys, a laptop locked in the trunk and some very kind friends who helped me arrive on campus just in time to teach my class.  When I first started teaching a few years ago this scenario would have been my worst nightmare, but I actually walked into the classroom pretty calm.  I was building off of an activity that we had done the class period before, the subject was something I know very well and I was prepared for the class.
In the previous class period students had watched videos of crayfish fighting, we talked about how to construct an ethogram and then they had scored two different fights for fight intensity, looking for specific behaviors.  I had wanted to bring crayfish into the classroom, but I have a 50 minute class period with classes immediately before and after me in the same room and 64 students (active learning fail or sane alternative choice?).  I had the students look at and discuss the data and then we had a class discussion about the types of questions you can ask with this type of data.  I drew the approximate results of a couple of experiments on the board and we discussed them.  Overall, the class went well.  One thing I noticed was that without the distraction of the computer I found myself interacting with the students more.  I actually walked into the middle of the classroom to talk to the students, and I don't think the students lost anything.  The graphs I drew on the board were proportionally accurate if not exact and allowed us to talk about the experiments.
For some time I have wondered if my use of powerpoint makes me a worse teacher.  When I was an undergrad, we didn't have this fancy-schmancy powerpoint.  My professors used overheads and filled the board with diagrams and writing.  I took actual notes on paper, that were of spotty use to me later, feverishly scratching away to get it all down.  I always wondered how they did it.  I experienced my first powerpoint lectures in grad school and I often found them harder to follow.  The tendency is to put too many things on one slide and go through the slides way too fast.  I also think that watching a powerpoint presentation is very passive, like watching a TV show.  As a lecturer making the powerpoints takes FOREVER and sometimes I wonder if I could spend that time preparing in other ways. I have often wondered, if I am serious about being a good teacher should I ditch the powerpoint entirely?

There are a few things that keep me from doing this:

1. The students expect it.  All of their classes us powerpoint and they are used to getting information this way and having access to the slides afterwards.
2. I have TERRIBLE and I mean terrible drawing skills and handwriting.  I worry that anything I write or draw on the board will be completely unintelligable.
3. I really like having nice figures to point to.
4. Making the powerpoint helps me organize my thoughts and the structure of the class.
5. I can continually tweak the presentation from year to year and make it better and then still have those changes readily available to me when I go to give the lecture again.

There are some things I have done to try and make the presentations better.  I am sure to include lots of discussion questions and think-pair-share activities.  I try to think of the powerpoints more like old school slides; I make them mostly pictures or figures and then explain them.  I consciously try to slow down.  When I first started teaching I worried about running out material in my class period and would prepare almost a slide a minute (my poor students).  Now I'm lucky if I get through 20 slides in a 50 minute class period, so I feel like I'm doing a better job.  Still, if I were braver, I think I would ditch the slide show entirely, at least some of the time.

I would love to hear your opinions in the comments.  What's the worst powerpoint presentation you've ever had to sit through?  Do you use powerpoint when you lecture?  How do you use it?  Is an old school chalk talk with class discussion really the best way to go?

Triathlon Training is Changing My Life

My goal is to compete in an Olympic distance triathlon one month from now 1.5K swim, 40K bike, 10K run.  I believe this will take me a little over 3 hours.  I decided to train for a triathlon because I wanted to set a goal for myself that was difficult, but concrete and achievable.

I have gone through some tough years and it had been a long time since I had felt like the best version of myself.  My career was off track from what I had envisioned for myself. I was allowing myself to wallow and live a bit aimlessly.  I would wake up in the morning with a sense of anxiety and a long list of disparate goals and tasks in my head including things like work on papers, finish job applications, write grants, run PCR in lab, research career opportunities, workout, cook a healthy dinner...  Each of these tasks felt simultaneously monumentally important and completely pointless.  Often I would procrastinate, unable to decide which task to tackle first and accomplish none of them.  Every day felt like a little test that I was failing. 

I had also experienced some physical setbacks.  A broken ankle led to a period of inactivity.  I trained for and completed two half marathons, but then had a bad case of plantar fasciitis in my foot and had to stop running completely for over 6 months.  I was experiencing back pain that disrupted my sleep and I would often wake up in the morning in physical pain.  I chalked up these aches and pains and inability to really get back in shape to my age.  Maybe this is just what it's like once you hit your mid 30s.

At the beginning of this year I set goal to complete a triathlon before the year was out.  It was something I had been thinking about for some time and for some reason I just decided to do it and posted my goal on Facebook.  At this point I was already on the upswing.  I had been adjunct lecturing for several semesters and was feeling comfortable and confident in the classroom.  I love teaching because I like working with students and having an excuse to read about and research areas of Biology outside of my direct field of study.  Teaching also provides a schedule and set of concrete tasks and I need these things to structure my day and be productive.  In addition, the foot pain had inspired me to buy a bicycle (the missing piece of my tri) and I was really enjoying riding it.

I started out the year by focusing mostly on swimming.  I was a swimmer in high school and college.  During these years swimming defined me as person; I spent more time and energy swimming than doing anything else in my life.  I got up for 5:45 AM workout and after school was back either at the pool or weight room.  I was exhausted all of the time and I hated getting up early every day.  What I loved most about swimming wasn't competing in meets but the amazing feeling I would have after a really challenging workout or set.  The feeling of pushing yourself to the brink of your ability, living up to the challenge and being completely spent.  I loved spending time in the water and in the summers I spent the whole day at the pool, swimming, coaching and lifeguarding. I was never the fastest swimmer and I had many disappointments over the course of my career, but I trained hard and couldn't imagine my life without swimming.

At the beginning of my senior year in college I quit swimming.  It was decision that surprised everyone, including myself.  I didn't have a concrete reason not to swim my senior year, except that suddenly I was done.  I didn't want to do it anymore; I was worn out and didn't love it the way I once had. I didn't see a reason to grind it out one more year just because it was my senior year.  I hung up my suit and didn't touch the pool for over a decade; the idea of swimming casually was too painful. I was working on an independent project in a Biology lab for my senior thesis and was excited to spend more time doing that.  Biology research took the place that swimming had once filled in my life.

When I started my first postdoc I decided to look up a Master's swim teams in the area.  Enough time had passed that I felt that I could enjoy swimming without feeling pressure to live up to my old times.  I put on my cap and goggles and jumped in the pool.  The sensation of swimming, staring down at the black line, counting my strokes, flipping at the wall, smelling the chlorine, was immediately familiar and comforting.  I couldn't believe how fun it was!  Every time I made it to practice I would be grinning, the coaches probably thought I was crazy.  Swimming and swimmers were the bright spots in my week that kept me going.

Then came the end of my first postdoc, a move and the aforementioned difficult times.  I found a new Master's team, but had difficulty making the scheduled workout times and attended practice very spottily for the first couple of years.  Then at the beginning of this year I committed to doing what I had to to make a swim workout at least two three times a week and during my month break between spring and summer sessions I swam almost every day.  That was the boost I needed to increase my fitness to the level where I could start training for a triathlon.

In May I signed up for an Olympic distance tri in Santa Cruz, CA on September 28th.  I started adding running and biking workouts.  A swimmer friend lent me a fast road bike and I've gotten more and more comfortable on the bike and gone on some long rides.  Starting at the beginning of July I started a training plan for the triathlon that involved swimming, biking or running 5 to 6 times a week.  I've gone on bike rides that are longer and hillier than I would have attempted otherwise.  I've learned to fix a flat tire.  I'm learning how to fuel myself during these workouts that are longer than I've ever done before.  A few weeks ago I started doing something I never would have done if I weren't training for the Triathlon.  I got up at 5 AM to drive to Aquatic Park in San Francisco and swim in the bay without a wetsuit.  The feeling of being in the bay, in the dark and silence was amazing!  Then last week I did something I never thought I would do again, I got in the water for a 5:45 AM pool workout. 

Suddenly within the last few weeks I feel better than I have in years.  Every night I fall asleep at 11 and sleep through the night.  I have little to no back pain; I wake up with a sense of calm and purpose instead of dread and anxiety.  I feel strong and healthy.  Even more surprising I feel mentally and emotionally healthier.  I have more energy to tackle my day and I'm feeling more excited and engaged in science than I have in years.  I feel more like myself.

Yesterday I competed in my first triathlon, a sprint distance half the length of my goal, and it was a blast!  The bay was warm and I felt relaxed and confident in the water and got one of the fastest swim times.  The bike was so much fun!  It was my first time riding a race and it was so nice to be able to just ride fast without worrying about cars or traffic lights.  The run felt slow but I kept a steady pace.  When I finished I was surprised to find out that I had won 3rd in my age group.  Most of all I felt really good in my body.  Four weeks to the Olympic distance triathlon and then we will see what lies ahead.  I hope that I can achieve a balance between my athletic and intellectual goals and maintain the sense of happiness and well-being that I feel right now.

Adventures in Scientific Teaching: 3 First Days

You might be surprised to hear this but professors are just as nervous for the first day of class as the students are, or at least I am.  I, like many scientists, am a bit of an introvert.  Meeting a lot of people all at once, in any context, has always been anxiety provoking for me.  In the last three days I have met over 100 students.  I'm teaching two lab sections of 21-22 students each and one large lecture of 60 students.  Here I am looking out at all these eyes with expressions of nervousness, skepticism, determination, excitement, boredom...  They are evaluating me as as professor, trying to figure out how tough or easy my class will be, how much they will be able to get away with and whether they can trust me to respect them.  When I first started teaching I was also nervous about being taken seriously and conveying intellectual authority.  I would deal with my nervousness by putting a bit of a wall between myself and the students and treating the lecture as a performance where I would try to impart as much information as possible. 

Since then I have changed my approach to first days, due in part to a workshop through a program called Faculty Explorations in Scientific Teaching (FEST).  I go in to class trying to channel my most extroverted self.  I greet students individually as they enter the classroom and introduce myself by my first name.  Then, towards the beginning of class I ask students to fill out a notecard with their name, major/career goal, something fun they did over the summer and one unique thing or hobby.  I then have students stand up, walk around the room and introduce themselves to each other and talk about their summer vacation.  Before taking the workshop I wouldn't have thought to do this in class, it seems maybe frivolous, or that I'm trying to fill time when they could be learning something.  But I have been surprised that allowing students to talk to each other really sets a positive and cooperative tone for the class.  The other bonus is that I then get to sit my office afterwards and read the notecards.  The notecards make me smile and laugh.  Some of the students share such surprising and funny things about themselves. My favorite this year is a student who told me that he is color blind, but his favorite color is "green." My students traveled all over the world this summer, some tackled a difficult hike for the first time or spent the summer studying for MCATs.  Reading these notecards makes me feel good about my students and when I look out at all of those staring eyes they feel a little bit less like strangers.

I won't lie, teaching while actively engaging with the students takes a lot out of me, sometimes I go home and just need to lie on my couch in silence and talk to no one, but it is also a lot more fun and more rewarding.  I'm looking forward to good semester full of active and cooperative learning.

The Seven Stages of Grief for an Academic Career

Bioluminessa where have you been, you might ask.  The last two years have been a wild ride.

Here is a synopsis:

The good: Discovering a love for teaching and learning about pedagogy research that emphasizes student engagement and inquiry.

The bad: Writing many grants applying for research funding and not yet being successful.

The ugly: Broken ankle while sampling tidepools.

            I am now halfway through my 35^th year and I have to admit I’m not where I thought I would be.  When I graduated with my PhD at the age of 29 I was very naïve and a little bit smug.  I had secured my first postdoc and imagined that within 5 years I would be starting out in a tenured faculty position.  I knew that it would be difficult and competitive, but I thought all I would have to do is stick it out and work hard.  But life doesn’t always work the way you think and there were two things I didn’t anticipate.  The first is just how constricted the funding situation has become and the second is how my priorities have changed as I have gotten older.  After my first postdoc fellowship ended, I moved to the city where my husband wants to live and has a job to look for a second postdoc or faculty position.  I emailed many PIs with interests in my area none of whom had funding for a postdoc.  I started writing grants with a PI with research interests similar to mine and also accepted some adjunct lecturer positions teaching at couple of different universities.

I have come to realize that for a variety of reasons I am unlikely to achieve my lifelong goal of becoming a tenured track professor.  I am letting go of some of the constant anxiety of constantly worrying about the treadmill of the next paper, the next grant, the next position and trying out new hobbies and interests.  To get to this place I went through a lot of heartache and depression that closely followed the 7 stages of grief.

1. Shock and Denial – I know that I can make it.  I just have to keep putting myself out there, keep applying for grants and jobs, keep e-mailing potential advisors.  I know I will get the next grant and produce amazing work.

2. Pain and Guilt – I’m just not good enough.  I’m not worth anything if I can’t make this work.  I’m trained to be a science researcher and if I can’t make it in this field I have nothing else to offer the world.  If I don’t have an academic career then I am a failure who is wasting my PhD and my years of training and education are useless.

3. Anger and Bargaining – The system is set up against me.  I was tricked and I’ve been participating in a Ponzi scheme all along.  Our government and academic institutions say that they want to recruit young people into science but don’t support the large number of passionate and well-trained existing scientists who would like to work.  The republican congress is ruining the country doesn’t seem to want to spend money on the things that matter anymore.  Bargaining - if I feel constant anxiety and work every second to the detriment of my sanity and health I will get an NSF grant.

4. Depression – Why bother to get out of bed.  I don’t have to go to the lab; I’m not being paid. What is the point if I’m never going to have a job anyway.

5.  The Upward Turn – I realize that I find teaching surprisingly fulfilling and rewarding.  I participated in workshops focused on scientific teaching and found an approach to thinking about teaching that I find intellectually interesting.

6. Reconstructing and Working Through – I am reengaging with life and taking advantage of the opportunities that I have.  I do my best to apply scientific teaching strategies to my classroom, I have become more engaged in the community at the universities where I teach.  I am also spending more time in the lab.  Instead of being bitter and anxious that I don’t have funding I am realizing that I am lucky that I have a relationship with a PI who is willing to give me a fair bit of freedom to work and explore.  I am engaging more with the students in the lab and enjoying my role as a research mentor.

7. Acceptance and Hope – I am beginning to reach this stage.  I am realizing that I don’t deserve to be handed a grant or a job on a silver platter anymore then anyone else.  I have always been an overachiever and in the past I have attained many things that I tried for with just enough effort.  If I’m not willing to make the sacrifices necessary to achieve a research position, such as being willing to move anywhere in the country or work insane hours, ultimately that is my choice to make. I’m still in a tenuous position with no full-time position.  I know that adjunct lecturing has the potential to be a sticky floor with uncertain long-term prospects.  I’m not sure where I’m going to end up, but I’m willing to enjoy the ride and push myself to be the best person that I can be.

Have you had similar experiences in academia?  I would love to hear about your path.

Songbird Duets

Are you and your significant other perfectly synchronized to sing in sweet, sweet harmony?  A paper published recently by Eric Fortune and colleagues in the journal Science has shown that couples of one species of songbird called the plain-tailed wren (Pheugopedius euophrys) do just that.  Plain-tailed wrens live in bamboo thickets in the Andes in South America.  In most species of songbirds only the male birds sing and they perform their song to attract females and defend their territory.  What is unique about the plain tailed wrens is that both males and females sing in a duet.  They alternate singing parts (or syllables) of the song so that it sounds like the whole song was produced by only one bird.  This takes remarkable coordination between the male and female birds.  Males and females each produced the same syllables whether singing together or alone but when both partners sang together they adjusted the amount of time between syllables to coordinate with their partner indicating that they were listening to both their own voice and their partner's during singing.  It appears that the females may be largely responsible for keeping the song on track.  Male songs were more variable and sometimes males would stop singing prematurely but the female would continue the song allowing the male to rejoin her.  The researchers recorded the activity of neurons in region of the brain that drives the motor output of the song called HVC.  In most birds this region of the brain will respond to auditory playback only of the song it actually produces.  In duetting wrens, however, the neurons responded best to playback of the duet song in its entirety even though each wren only produces half of the song.  The exact function of the duet is unknown, though it is thought to play a role in territory defense.  Could it be that the females are choosing males based on their ability to listen to and synchronize with her?  Regardless this is an intriguing example in which these birds brains have become adapted not only to produce complicated vocalizations but also to precisely coordinate with a partner.

A shortage of scientists?

I was just listening to the slate political gabfest and they were discussing Florida Governor Rick Scott's comment that he thinks that state funded colleges should shift funds away from degrees like psychology and anthropology and shift funding to subjects such as science and engineering, because there are more job opportunities in those fields.  David Plotz was arguing that maybe we should shift funding for undergraduate education to science since we're talking about allocating taxpayer dollars and we want to have the greatest benefit for society.  There is much to argue about the intrinsic value of a balanced liberal arts education and the depth and creativity that a variety of disciplines contribute to society.  However, I would like to challenge the second half of this assumption.  Are there REALLY more jobs available in science?  Where are they?  Are we really seeing that there are lots of great science jobs and not enough people to fill them?  From where I'm sitting this certainly doesn't appear to be the case.

I would argue that if there is a diminishment of science in this country that it is not a pipeline problem, at least not in biology.  There are 1,000s of scientists called postdoctoral researchers many with  a decade or more of experience toiling away for very little pay just waiting for their potential to be tapped.  Biologists who complete a Ph.D. face stiff competition for only a few academic jobs and the funding to support independent research through the National Institutes of Health and National Science Foundation has been shrinking or holding steady.  This article from Science Insider states that the funding rate for grant proposals will likely fall below 20% in 2011.  These low funding rates have an especially grim impact on young scientists; this is the money that science professors use to fund graduate students and postdocs to work in their lab.  On top of that the few postdocs lucky enough to find a job in academia will have trouble getting their research programs off the ground.  If the United States wants to promote science breakthroughs we need to commit to funding scientific research.

Maybe you would argue that funding academic research is not promoting the kind of science that we want.  There are many arguments for the necessity of basic research; biotech and other companies participating in research that can contribute to human well-being rely on the discoveries made in the course of pursuing of scientific questions that may not initially seem directly applicable.  Aside from this I know many postdoctoral researchers who enjoy benchwork and would be happy to leave academia for a steady paycheck, some choice in their location and to continue doing what they love.  Is there a way the U.S. could invest in creating more jobs for people with Ph.D.s to work on the nation's scientific problems outside of the university system?  I have to say, the way it is now, I would not necessarily suggest that a student pursue science as career unless they were really passionate about it.  I am not arguing that science education is not important but what does it mean to encourage more undergraduates to study science if we as a society are not willing to invest in scientific research for the long term?

Pardon me, are you still using that shell?

One animal that is common in tidepools the world over are hermit crabs.  Peering into a tidepool you might see a snail that appears to be scurrying around sideways and then you'll see the little eyes and legs peeping out.  A hermit crab!  Unlike other crabs, hermit crabs have a soft, curled up abdomen that must be protected and hermit crabs depend on using snail shells as their little house.  Crabs (and all other arthropods) must shed their shell in a process called molting in order to grow and hermit crabs undergo an additional danger because as they grow they need to find new shells.  A hermit crab is always on the lookout for a new and better shell.  What are the chances of finding a shell of exactly the right size?  Since every hermit crab is looking a slightly bigger shell when one hermit crab changes shells then this will vacate a shell that is suitable for another, slightly smaller, hermit crab.  In the wild hermit crabs have been observed participating in an amazing behavior called a vacancy chain in which they will line up in order of size in order to take advantage of a new shell.  How does this come about?  For one thing the smell of dead or dying snails or other hermit crabs have been shown to attract hermit crabs resulting in several hermit crabs congregating and competing for new shells.  Hermit crabs will fight for shells by pushing each other with their claws.  Rotjan et al. (2010) reported in Behavioral Ecology that when hermit crabs are living in high density they will exhibit several interesting behaviors that lead to the establishment of a line organized by size to facilitate an orderly change into new shells.  For example a hermit crab that encounters a shell that is too large for it to inhabit comfortably will wait within the area of that shell for up to an hour.  This behavior increases the chances that other hermit crabs will show up allowing the waiting hermit crab to acquire a shell of the appropriate size.  In addition, in the presence of a large shell multiple hermit crabs will participate in a behavior called "piggybacking."  A crab will grab onto the back of crab slightly larger than itself.  Once a crab large enough take advantage of the new shell arrives then the hermit crabs form a line in order of size.  When the largest crab moves into the new shell then the next largest crab moves into the now vacant shell and so on down the line until the very smallest shell is left behind.  I find this to be a fascinating and surprisingly efficient way for everyone to get a new, bigger house!

Tidepools!

Last week I participated in Marine Biology camp for high school students in Bodega Bay California.  Students collected animals from the tidepools and mudflats, took them back to the lab to observe them and then designed and conducted their own experiments.  It's so fun to get the chance to approach science again from this basic level of fascination and curiosity which is what drove me to study biology in the first place.  Some of my earliest memories are of exploring the tidepools of Islesboro, Maine finding muscles, barnacles, green sea urchins, brittle stars and crabs.  I would collect shells and seaglass which seemed like mysterious gifts from an unknown world.

Rocky Intertidal habitat in Big Sur, California.  Picture by Vanessa Miller-Sims

Tidepools are special place at the interface of land and sea and the organisms that live there must deal with living in an ephemeral habitat that is constantly changing in both time and space.  The intertidal zone is defined is the area that is out of the water at low tide but completely covered at high tide. Organisms living in this environment are exposed to wave action, changes in temperature and salinity, exposure to air and sun in addition to competition for space with other organisms and predation.  The intertidal is divided into zones depending on how much of the time the organisms that live there are submerged.  Organisms that live in the highest part of the intertidal zone are submerged for the least amount of time and must have adaptations to avoid drying out while the lowest part of the intertidal is submerged most of the time and thus provides the most stable habitat.

Barnacles in Garrapata State Park in Big Sur.  Picture by Vanessa Miller-Sims

These barnacles are not covered by water and as you can see they are closed fast to keep them from drying out.  When the tide rises and they are once again covered they will open up and feed on small particles suspended in the water.

Big Sur Tidepool. Picture by Vanessa Miller-Sims

A look into a submerged tidepool shows anemones snails and coralline algae.

A good read for lovers of Monterey Bay

I just finished reading a book called The Death and Life of Monterey Bay A Story of Revival by Stephen R. Palumbi and Carolyn Sotka.  It was a fun, interesting and quick read that I would definitely recommend to anyone who has visited and been enchanted by Monterey Bay or who is interested in marine conservation.  The first time I visited Monterey and Pacific Grove I immediately experienced it as a magical place full of history as a seaside fishing town and replete with natural beauty and sea critters.  The Monterey Bay Aquarium does an amazing job of showcasing the diverse and plentiful marine life of Monterey Bay and I love gazing out watching the sea otters float on their backs in the kelp.  The aquarium is built within an old cannery building on Cannery Row and I had known that the canneries once fished almost unfathomable numbers of sardines out of the bay before the fishery collapsed.  However, before reading this book I had not fully understood the extent of the environmental devastation that Monterey Bay had endured.  During the course of the 19th and first half of the 20th century the bay's resources were exploited one by one.  First the otters were hunted to the brink of extinction (and were in fact thought to be completely extinct), followed by California gray whales and abalone.  By the time the canneries started up the bay was already a greatly changed place.  The canneries not only fished out the sardines but also released large amounts of pollution into the bay and apparently the rocky shore was covered in rotting fish and flies.  Today Monterey Bay is an uplifting testament to the fact nature can regain a foothold when we leave a place alone and implement smart management.  The biggest change to Monterey Bay has been the return of the sea otters which have allowed kelp forests to flourish by keeping herbivorous sea urchin and abalone at bay.  The kelp in turn provides habitat for numerous fish species and allows a whole ecosystem to flourish.  The book tells the story of the rise and fall of Monterey Bay and the characters that have inhabited its shores over the course of the last 200 years.  

Keep those mozzies (mosquitoes) away!

Mosquitoes are a fact of life in the summertime but have you ever wondered how they track us down so quickly?  We've all had the experience where we're enjoying a nice summertime picnic and as soon as dusk arrives the mosquitoes show up one by one and start attacking.  How do they find us so quickly?  Mosquitoes are attracted to carbon dioxide, which seems a little unfair.  We release carbon dioxide every time we breathe out and to be even more tricky mosquitoes are specifically attracted to intermittent pulses of carbon dioxide.  Mosquitoes can follow carbon dioxide odor upstream to it's source (us).  This is always particularly clear to me when I am camping and I wake up in the morning to see both the condensation on the tent surfaced caused by my breath and the mosquitoes longingly pressed up against the screen of the tent.

Picture by JJ Harrison found on Wikipedia.org

Mosquitoes and other animals (including us) perceive a smell when small molecules in the air bind to a receptor and activate an olfactory neuron which then passes the message on to the brain.  Mosquitoes and other bugs have these receptors on an antennule on their head.  Receptors bind molecules based on their shape and chemical composition.  Most receptors are not perfect if a molecule is similar in shape to the intended molecule or present in a high concentration then it too will bind to the receptor.  A recent paper published in Nature (474:87-91) looked for molecules that would bind to the mosquito carbon dioxide receptor thus confusing the mosquito and limiting its ability to find us.  The scientists recorded the activity of the carbon dioxide receptor neuron and found one compound which activated the receptor for an unusually long period of time.  Such strong long-term activation of the carbon dioxide receptor could disable the response olfactory receptor neuron to carbon dioxide and should limit the mosquitoes' ability to track the carbon dioxide odor.  This is in fact what the researchers found; mosquitoes were placed in a wind tunnel with carbon dioxide being released from an air cylinder.  Fewer of the mosquitoes that were treated with molecule that activated the carbon dioxide receptor were able to find the carbon dioxide source and those that did took longer.  We can't stop breathing so it's a relief by blocking the ability of mosquitoes to detect and track carbon dioxide we may be able to hide our distinctive long range scent.

Stickleback Evolution

Sticklebacks are an excellent species for studying how populations adapt to their local environment through natural selection because nature has done an experiment for us.  The oldest (ancestral) population of sticklebacks is a marine form that spends most of its life in the sea and returns to freshwater to breed.  Just over 10,000 years ago much of North America was covered with ice and as this ice receded lakes were formed.  At that time different populations of marine sticklebacks found their way to and colonized freshwater lakes, these populations underwent rapid adaptation to the freshwater environment.  For example fish in freshwater lakes tended to lose the spines on their pelvis and the armor plates usually found in marine fish.  This resulted in fish from freshwater populations looking remarkably similar to each other even though each population is more closely related to the marine population than to each other.  This phenomenon of populations that live in similar environments developing similar morphological (body shape and structure) characteristics is called parallel evolution. 

Natural selection works because individuals that are better adapted to their habitat live longer and have more offspring than those that are poorly adapted.  However, in order for natural selection to act there must be variation in the natural population.  Where do the morphological characteristics seen in the freshwater populations come from?  The body plan of every organism is encoded in its DNA; genes are regions of the DNA that encode proteins.  Every aspect of an organism's anatomy, physiology and behavior is dependent on the structure of these proteins and where and when they are expressed.   Variation could result from differences in the DNA sequence of a gene itself which would alter the structure of the protein.  However changing the structure of a protein is likely to diminish or even inactivate its function.  Most proteins (and thus genes) act in many different parts of the body and at different times; changes that broadly disrupt protein function are likely to do more harm than good.  On the other hand changes in the regulatory regions of DNA control where, when and how much of a protein is expressed will result in smaller, more targeted changes.  Differences in these regulatory parts of the genome may have the specific types of effects that we see in stickleback populations and allow for rapid adaptation.  This is exactly what researchers in Dr. David Kingsley's lab at Stanford University have found.  They were able to locate specific genes that account for morphological differences between populations however in each case genetic differences were found not in the gene region that determines the structure of the protein but rather in regulatory regions that control when and where the gene is expressed.  This is an exciting result that shows that variation in a single region of DNA can have a big effect on the morphology of a particular body part without causing overall deleterious effects.  This type of genetic variation would allow for the rapid adaption to new environments seen in stickleback populations and could eventually lead to the creation of new species.

Isolation and Adaptation

Biologists agree that the huge diversity of species seen on earth have evolved from a common ancestor through the process of natural selection.  However the details of how this occurs have been hotly debated.  How do populations of organisms adapt to their local environment?  How are new species formed?  One theory called gradualism (which was the mechanism initially proposed by Darwin) suggests that adaptive changes occur in incremental steps.  So for example, if a bird had a short beak which was well adapted to environment A and some individuals from that population suddenly found themselves in environment B (lets just say that it is and island and there no subsequent contact between the two populations) and environment B favors individuals with long beaks then there will be natural variation of beak length within the population and those individuals with longer beaks will survive better and produce more offspring.  Over many generations mean beak length will become longer and longer until eventually population B have longer beaks than population A.  Such differences between populations could be modulated by relatively small changes in a large number of genes.  One question is whether adaptive changes can also occur on a more rapid timescale.  Examination of the fossil record indicates that in many cases a species changes very little over time and speciation events are relatively rapid (on a geological time scale) leading to an idea called punctuated equilibrium.  One question is whether traits instead of shifting gradually through intermediate stages can be changed directly from one state to another.  Using the previous example immediately after the birds from environment A colonized environment B the vast majority of birds would have relatively short beaks but a few individuals would have substantially longer beaks creating a bimodal distribution of beak size.  The longer beaked individuals would survive better and produce more offspring and over time the majority of individuals in population B would have long beaks.  In this case beak length would likely be controlled by a small number genes such that changing the regulation of one or a few genes would result in large changes in the size of the beak. 

Stickleback fish have provided a great natural experiment for studying evolutionary mechanisms.  The marine form of sticklebacks have invaded many North American lakes in separate colonization events.  Once a stickleback population becomes established in the lake environment several adaptions occur including a loss of armor plates and reduction of the pelvis.  Comparing marine and freshwater populations has allowed evolutionary biologists to observe how these fish adapt to their new environment and in some cases discover the underlying genetic mechanisms.

Tomorrow: What do sticklebacks have to tell us about the mechanisms of adaptive change?

Threespine stickleback (Gasterosteus aculeatus)