Power Posing for a Successful Defense

   I had my dissertation defense last Friday! In my department we present an hour long seminar about our research that is open to the public and then have a closed-door discussion with professors only to talk about the research and final write-up in more depth. Afterwords a decision is made about whether or not you will be awarded a PhD. I passed and now only have some revisions and paperwork to fill our before my PhD will be finalized. Super exciting times!

A postdoc-pal of mine sent me a link to this video a couple of weeks ago. This presentation discusses studies looking at how standing/sitting in "power poses" can influence empowerment and confidence. It is a really great presentation and something to think about for anyone who is going on an interview or who has to give a big presentation. I have to admit that when I was setting up the half hour before my presentation I was doing some power posing to get ready. My favorite, the Super Woman pose.

Amy Cuddy: Power Poses

Amy Cuddy revealed that we can actually change feelings we have about our own status through the physical positions we take with our bodies. Her research participants had higher levels of testosterone and lower levels of cortisol after only two minutes in a “power pose”. Cuddy asked if such findings can have wider implications for empowerment training.

Is the Title of your Scientific Publication Important?

I just had a manuscript accepted for publication with the caveat that I needed to change my title. The comment was that papers with 'witty' or 'cute' titles are cited less often than papers with more serious titles. The editor mentioned that this had been shown in a study and I was interested to read about their findings.

The two studies I came across relating to this topic were:

1) Hamid R. Jamali and Mahsa Nikzad. 2011. Article title type and its relation with the number of downloads and citations. Scientometrics 88: 653-661.

2) Itay Sagi and Eldad Yechiam. 2008. Amusing titles in scientific journals and article citation. Journal of Information Science 34: 680-687.

In the first study (the title says it all topic-wise), they looked at a bunch of articles published in PLoS. Then they categorized the titles into three types: Declarative titles that include the main conclusions, Descriptive titles that only include the subject of the article, and Interrogative titles that indicate the subject in the form of a question. They also looked at the number of substantive words and whether or not there was a colon.

There main findings were that there was a difference between the types of titles in terms of the numbers of downloads from most downloaded to least Interrogative, Descriptive, Declarative. Whereas both the Descriptive and Declarative were cited equally and those with Interrogative titles were cited less often. Articles with longer titles tended to be downloaded less often but the title length was not correlated with citations. And finally titles with a colon get fewer downloads and citations.

Based on that, I think that the title of the first paper out from my dissertation will probably never be cited.  

Budke, Jessica M., Bernard Goffinet, and Cynthia S. Jones. 2011. A hundred-year-old question: is the moss calyptra covered by a cuticle? A case study of Funaria hygrometrica. Annals of Botany 107(8): 1259-1277. 

A question, a colon, and probably way too long. I wonder if I also loose points for the multi-hyphenated word? Maybe the cool science will overcome the flaws in the title.

They also talked about the fact that anyone can download an article, including students or members of the general public who are interested in a topic. However, citations are only from other scientific researchers. Hence titles that are more easily accessible or are more interesting may get more notice online but may not be cited by other members of your field.

As for the other paper, that gets to the title of the second chapter of my dissertation.

Beneath the Veil: The calyptra cuticle matures before the sporophyte cuticle in the moss Funaria hygrometrica.

So my logic behind this title is that the term calyptra comes from the Greek word kalyptra, which means veil or hood. It is a little cap of gametophyte tissue that covers the sporophyte apex throughout development and protects the underlying apex from dehydrating. And the study focuses what happens in terms of the cuticle development on the sporophyte beneath this cap. I thought that it was catchy.

I used a similar version of this title at the 2010 Botanical Society of America meeting. My talk was really well attended and I even had several people mention to me that my fun title had caught their eye in the program and influenced their attendance.

In the second paper, listed above, articles with an amusing title were found to have fewer citations. It was ok to have a pleasant title, but amusing titles may make people think that your science is not rigorous or thorough. 

I am still a firm believer that a fun talk title helps to pull people in to your presentation, but I will be changing this title for my Ch 2 manuscript as the editors suggested. Definitely some ideas to keep in mind when coming up with a title for your manuscript. Not that citations are everything, but having other researchers read your study and then connect it to their own is important for integrating your research into the larger scientific discourse.

Stressed out Sperm

What happens when you stress out moss sperm? That was one of the questions that researchers asked in this study.

Todd N. Rosenstiel and Sarah M. Eppley. 2009. Long-lived sperm in the geothermal bryophyte Pohlia nutans. Biology Letters 5: 857-860. 

Not only did they look at the impact of high temperature, but they also looked at sperm concentration, rainwater vs. deionized water, and the addition of sugar on sperm survival. 

In general they found that moss sperm are pretty long-lived, relatively speaking, with 20% survival after 100 hours for all dilution levels. This is pretty cool because the sperms may then be able to be transported by animal vectors or survive in a small drop of water until more water forms a film that they can use to swim to a female.

They found that sperm lived longer when sucrose was added. You might not think that moss sperm would have access to external supplies of sugar. It is not like they swim through maple syrup, but when dry bryophytes are rehydrated they release sugars into the surrounding water and these could be used by swimming sperm. Thus they could live longer and have more energy to swim to females that are further away.

The sperm were unaffected by temperature and survived at the same levels at both 22 and 60 C (~72 and 140 F). This is a pretty dramatic thermo-tolerance. Imagine the difference between room temperature and slightly hotter than the record temperature for Death Valley. I can't quite imagine being somewhere that hot, but it seems pretty extreme! The species they studied (Pohlia nutans) grows in geothermal areas and thus may be unique in terms of its tolerance for high heat.

Overall I think that it is a really cool study!

Tripods for BryoPhotography

I got an email a few weeks back asking about what types of tripods I would recommend for taking pictures of bryophytes.  I am not sure what other folks use, but I have two different tripods that I like pretty well. I have a GorillaPod Original and a Canon Mini Tripod 7. I use them both with my Canon PowerShot A710 IS, which is the camera that I have been using for the past 4 years for the images on this blog.

I have used them both in the field and laboratory, but find that I more often use the GorillaPod in the field and the Canon in the lab. The GorillaPod deals better with uneven surfaces and gets me closer to the ground, while the Canon is better for flat and stable tabletops where I can adjust the height of the mosses I am photographing. Though honestly for many of my photos in the field I sprawl on the ground and make a human tripod with my elbows and both hands on the camera, while holding my breath. However, my knees are starting to protest this method, so I will probably be relying on the GorillaPod more often.

GorillaPod Original with a little demonstration of the its grappling abilities as it clings to the arm of my office chair.

Canon Mini Tripod 7 

Moss Feet

Did you know that mosses have feet? No joke they do. But they don't use them to walk or run around. And thank goodness, because I am glad that I don't have to go chasing them when I go plant collecting.

Ok, bryophyte feet. At the bottom of the bryophyte sporophyte is the foot. It is the region where the un-branched sporophyte is physically attached to the leafy gametophyte. The foot functions in the transfer of nutrients from the maternal, leafy gametophyte to the sporophyte. These are a couple of good reviews about this region in mosses and across land plants.

Ligrone, R. and Gambardella, R. (1988) The sporophyte-gametophyte junction in bryophytes. Advances in Bryology 3: 225-274. (book)

Ligrone, R., Duckett, J. G. and Renzaglia, K. S. (1993) The gametophyte-sporophyte junction in land plants. Advances in Botanical Research 19: 231-317.

My thinking about bryophyte feet was stimulated by a question from a colleague in my department. They were teaching the students about mosses in the Introductory Biology class and were discussing why in old, mainly brown sporophytes of Polytrichum the foot remains green. Early in development the entire sporophyte is green and photosynthetic. Later in development the capsule and stalk turn brown/red and dry out.

Here are some reasons why I think that the foot may remain green long after the rest is no longer photosynthetic. These are just my hypotheses/ideas. I don't have any data or citations to back them up. (1) It is protected from desiccation by the surrounding leafy gametophyte and thus does not dry out. Resulting in it remaining green and hydrated for longer. AND/OR (2) Since it is involved in nutrient transfer from the leafy gametophyte to the sporophyte, it may remain metabolically active and functioning in nutrient transfer until late in sporophyte development. Being able to function in nutrient transfer would require that this tissue is still alive and maybe also photosynthetic = green.

You can see the foot of a moss sporophyte by gently pulling the sporophyte out of the gametophyte that it is attached to. I honestly only remember trying this on Polytrichum when teaching intro bio. I am definitely going to have to take a look at the feet of other species of mosses to see if they also remain green long after the sporophytes have become brown.

Hypothes.is on Kickstarter - Taking Peer Review to the Internet

I heard about this project over at Uncommon Ground. I think that sounds like a pretty interesting idea for evaluating information that is posted on the web. Check it out and see what you think.

Poop - Where Bryologists and Ornithologists Overlap

We read a paper last week in lab group about goose poop. Yes this is still a blog about about bryophytes and I am going to write about poop today.

M. Stech, E. Kolvoort, M. J. J. E. Loonen, K. Vrieling and J. D. Kruijer. 2011. Bryophyte DNA sequences from faeces of an arctic herbivore, barnacle goose (Branta leucopsis). Molecular Ecology Resources 11: 404–408.

In this paper, the goal was to optimize a methodology for extracting bryophyte DNA from the poop/faeces of the barnacle goose. Then they use the DNA to identify the different bryophyte species that the birds had eaten. It is pretty amazing that they were able to identify the mosses from the goose poop using DNA. I think that this sounds much better than digging through the poop trying to identify the bryohytes from small pieces of leaves.

I ran into a bunch of the ornithologists (the folks who study birds) who work in my department and we had a fun discussion about all the possibilities for studying bird poop and the plant contents of the poop. 

It made me think about the Science Communication seminar that I have taken and the book Don't be Such a Scientist that we read a couple of years back. One of the ideas in the book is that that there are several ways to appeal to an audience when communicating science. Intellect - Feeling - Humor - Sex. I think that bodily functions, including poop, could be added in too. Poop is definitely a topic for communicating science that appeals to everyone. Ok maybe appeals is the wrong word. But it is definitely a process everyone can relate to, whereas studying mosses can at times be a little esoteric.

I thought that it was a really fun paper and good science too!

Hot off the Geothermal Presses

 I read this study in the latest issue of the International Journal of Plant Sciences. I thought that it was a really neat study and is an easily accessible piece of scientific literature for folks to read who are not professional bryologists.

The premise - In stressful environments, studies suggest that sexual reproduction is favored. Researchers examine this idea in mosses across a geothermal gradient in Lassen Volcanic National Park in California.

Methodology - They collected data on sporophyte and gametoecia production from species in the field. (Yeah, gametoecia. I had to look this word up. It is both the gametangia and the surrounding leaves together.) They also collected data on temperature. The collection locations were divided up into geothermal and nongeothermal sites based on the temperature measures.

Also they ran a common garden experiment with Pohlia nutans to look at whether a genetic adaptation was limiting sporophyte production or if alternatively the extreme stress was the cause of low sporophyte production.

Results - Their results indicate that there were lower rates of sporophyte production, due to lower rates of gametoecia formation at the geothermal sites. These rates for both sporophyte and gametoecia production were higher at the nongeothermal sites. When plants from both types of sites were grown in greenhouse conditions these relationships disappear.

Implications - This study does not support the idea that sexual reproduction is favored in stressful environments. It actually shows the complete opposite for this species of mosses. Sexual reproduction decreases with increased temperature stress. The authors state that the "regression between temperature and sporophyte production was not high." And go on to suggest that other stresses such as heavy metals may be involved. They discuss that other studies in fungi and mosses have shown similar patterns and cite several studies.

I was wondering whether they thought that differences in light or perhaps levels of desiccation could be an influence too.

Sarah M. Eppley, Todd N. Rosenstiel, Camille B. Graves and Estefanía Llaneza García. 2011. Limits to Sexual Reproduction in Geothermal Bryophytes International Journal of Plant Sciences Vol. 172, No. 7, pp. 870-878.

Overall I thought that it was a really great study and a nice read. One odd fact is that they list 3M Corporation as one of their funding sources in the acknowledgements. I use a lot of post-it-notes to label and organize my research. Wonder if I could get them to sponsor one of my studies?

Postcards

 One of the postcards that I got this summer prominently featured mosses from northern California. A picture of the postcard is on the right. I also took a photo of the caption on the back. Check out the portion that my friend underlined. It reads "A variety of mosses are brought to blossom by winter rains." What strikes you about this sentence? How about the word blossom? Blossoming refers to flowers, and mosses don't have flowers! This is a common terminology mistake. People are much more familiar with flowering plants and when looking at mosses they typically try to use flowering plant terms. Mosses with sporophytes are often said to be fruiting or blooming. Figuring out what word to use can be a challenge. Sporulating? Sporophyting? Usually what I say is that they are reproducing and releasing spores. Most people are familiar with reproduction and then I can go on to explain more about spores if needed. 

This might seem like I am just being picky, but using the correct word is important for making comparisons between mosses and other plants. The little sporophytes that the mosses are producing are not the same as flowers, but are actually equivalent to an entire redwood tree! I think that comparison has much more wow factor that just being a gaudy flower.

This is the other mossy postcard that I have hanging on my bulletin board, below. Kathyrn is definitely winning the moss postcard competition, having sent me both of these. The stamp on the other side of this postcard even features a moss and fern filled glen. What's that, you say you can't see the mosses on the stamp? Well they are there. Look at that moist stream-side habitat. Those trees and the rocks surrounding the waterfall must be covered in mosses!

Relationships between the Three Groups of Bryophytes

I got an email this week from a colleague about the state of the relationships among the three groups of bryophytes: Mosses,  Liverworts, and Hornworts.

The first questions to consider - Are they three separate lineages? OR One monophyletic lineage?

If they are three separate lineages, what order should they be placed in relative to tracheophytes (plants that have tracheids, a special type of xylem)?

Well it all depends on which data are used.

Data from sperm ultrastructure (Garbary et al. 1993) and DNA data from entire chloroplast genomes (Nishiyama et al. 2003) points to the three groups being part of a monophyletic lineage, as in the diagram on the right.

However all the other studies that I can think of support these three lineages as independent and as a grade diverging prior to the evolution of the tracheophytes.

This phylogenetic relationship was proposed based on morphology, physiology, and biochemistry data (Mishler & Churchill 1984). Then subsequently supported by molecular sequence data (Mishler et al. 1994).

 

Another alternative hypothesis was supported by sporophyte morphological data (Garbary & Renzaglia 1998) and cox3 mitochondrial sequence data (Malek et al. 1996).

So, I think that this could be presented to students as an active scientific example of different data giving conflicting signals. Often science is much messier than we explain to students. They could be presented with multiple alternative hypotheses for these relationships and have to discuss the different scenarios or perhaps the different types of data used for each. 

However, if I only wanted to present one phylogenetic relationship to my students I would go with this one, below. This relationship is supported by Qui et al. (2006), which uses molecular sequence data from the chloroplast, mitochondria and nucleus on over 100 taxa. Others may disagree, but this is the phylogeny that I would recommend using as our most current hypothesis for teaching students about relationships among the bryophytes.

References

Garbary, D. J., K. S. Renzaglia & J. G. Duckett. 1993. The phylogeny of land plants: A cladistic analysis based on male gametogenesis. Plant Systematics and Evolution 188: 237-269.

Garbary, D. J. & K. S. Renzaglia. 1998. Bryophyte phylogeny and the evolution of land plants: Evidence from development and ultrastructure. Pp. 45-63 in J. W. Bates, N. W. Ashton & J. G. Duckett (Editors), Bryology for the Twenty-first Century. Maney Publishing, Leeds.

Kenrick, P. & P. R. Crane. 1997. The Origin and Early Diversification of Land Plants. Smithsonian Institution Press, Washington, D.C.

Malek, O., K. Lättig, R. Hiesel, A. Brennicke & V. Knoop. 1996. RNA editing in bryophytes and a molecular phylogeny of land plants. The European Molecular Biology Organization Journal 15: 1403-1411.

Mishler, B. D. & S. P. Churchill. 1984. A cladistic approach to the phylogeny of "bryophytes." Brittonia 36:406-424.

Mishler, B. D., L. A. Lewis, M. A. Buchheim, K. S. Renzaglia, D. L. Garbary, C. F. Delwiche, F. W. Zechman, T. S. Kantz & R. L. Chapman. 1994. Phylogenetic relationships of the “green algae” and “bryophytes”. Annals of the Missouri Botanical Garden 81: 451-483.

Nishiyama, T., P. G. Wolf, M. Kughita, R. B. Sinclair, M. Sugita, C. Sugiura, T. Wakasugi, K. Yamada, K. Yoshinaga, K. Yamaguchi, K. Euda & M. Hasebe. 2004. Chloroplast phylogeny indicates that bryophytes are monophyletic. Molecular Biology and Evolution 21: 1813-1819.

Qiu, Y.-L., L. Li, B. Wang, Z. Chen, V. Knoop, M. Groth-Malonek, O. Dombrovska, J. Lee, L. Kent, J. Rest, G. F. Estabrook, T. A. Hendry, D. W. Taylor, C. M. Testa, M. Ambros, B. Crandall-Stotler, R. J. Duff, M. Stech, W. Frey, D. Quandt & C. C. Davis. 2006. The deepest divergences in land plants inferred from phylogenomic evidence. Proceedings of the National Academy of Sciences of the USA 103: 15511-15516.

What kind of Scientist are You?

I spent the past couple of weeks helping a friend move across the country. While on our travels I read this post from one of the professors in my department at the University of Connecticut. The idea is that you can identify what type of scientist you are in a personality-test fashion, based on whether you are Theory- or Data-Driven and a Nerd or Adventurer. 

The four types of scientists are listed below and are defined here by Virginia Hughes.

The Data-Driven Nerd

The Theory-Driven Nerd

The Data-Driven Adventurer

The Theory-Driven Adventurer

This stimulated some fun discussions while passing the time on the drive. I am definitely a Data-Driven Nerd. The part of science that I enjoy the most is running experiments in the lab. Though I do like adventure I usually get my fix through vacation travel on my time off, not directly through my research. And writing up my experiments for publication is my least favorite part of the process. My friend on the other hand is a Theory-Driven Adventurer. She is a political geographer who does her research in southeast Asia. I went to visit her last year while she was in Malaysia. A vacation adventure for me. 

I thought that this was a fun way to think about ourselves as scientists and what drives our interest in the questions that we ask. And I wanted to spread the word.

What kind of scientist are you?

Another Moss Misnomer

I am always on the lookout for plants called mosses that are actually not. I visited the Missouri Botanical Garden with some friends while in St. Louis a few weeks back for the Botany 2011 conference.  There I spotted this plant labeled Moss Fern. It is Selaginella pallescens, which is a lycopod or more traditionally called a fern ally. It is distantly related to moss as they are both green plants, but is definitely not a true moss. It has both vasculature (internal plumbing of xylem and phloem) as well as true roots to anchor it into the soil and function in water uptake.

There is a lot of plant life going on in this photo. The Selaginella is located behind the sign-post and also directly to the left. A few other species made it into the shot including a palm in the upper left and some mosses in the lower left.

There were quite a few other spots around the garden where mosses were growing, however, none of them were labeled. It is a bit of a bummer that the mosses are so blatantly ignored at a botanical garden. Here are a few shots from mosses inside the Climatron.

 

 

In general the garden didn't seem to add any fake animals to add to the tropical ambiance, thus this frog below looked a little out of place.

Some additional photos of the garden plants and me constantly looking for mosses can be seen over at my friend Em's blog.