Field of Science

Persistent P's Permeating the Polytrichiaceae

In lab group last week we read an article about the moss family Polytrichiaceae. These are the mosses that have fabulous little lamellae on their leaves. Some species are quite common and can be found in open disturbed edge habitat. They can be recognized by their star-shaped form when viewed from above and they are often one of the largest mosses that you will see in the field.

Bell, Neil E. and Jaakko Hyvönen. 2010. Phylogeny of the moss class Polytrichopsida (BRYOPHYTA): Generic-level structure and incongruent gene trees. Molecular Phylogenetics and Evolution 55: 381-398. 

Species are typically grouped into the larger category of genera based on the morphology of the plants, their physical appearance. Thus all the members of the genus Atrichum (the smooth capped mosses) look similar to each other and the same for other genera such as Polytrichum (the hairy capped moss). Sometimes it ends up that these morphological groupings are confirmed by the DNA sequence data and all the members of the genus did descend from a common ancestor. Other times the DNA data shows that the members are not descended from a recent common ancestor and are instead distantly related. The morphology and the DNA evidence tell a different story. In this study both Polytrichastrum and Oligotrichum are composed of members that are distantly related. The later genus has a distinct geographic pattern with all the northern members being related to each other and all the southern members in the other group. Overall I think that it is pretty cool to explore these morphological hypotheses with DNA data. You never know what there is to be found. 

Another paper on this group of mosses by the same authors.
Bell, Neil E. and Jaakko Hyvönen. 2010 A phylogenetic circumscription of Polytrichastrum (Polytrichaceae): Reassessment of sporophyte morphology supports molecular phylogeny. American Journal of Botany 97: 566-578. 

Berry Go Round #33

The October edition of the plant carnival Berry Go Round has been posted at 10,000 Birds.  Enjoy!

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

Lack of October Posts

Ack! October has come to a close and I have not posted anything up on the blog. Here is the breakdown of what has been up in my mossy world over the past month.

- I have been thinking a lot about explaining my research to the general public in understandable terms.
What I do - I study mosses, small green plants. (visual here - I have my fingers less than an inch apart) All plants are covered by a waxy coating that keeps them moist inside, called a cuticle. (I make a motion of an invisible coating covering the surface of my arm.) My research focuses on how the waxy cuticle develops or forms on the mosses throughout their life. (Moving my hands as though something is growing or time is passing.) I use really powerful microscopes to zoom in to see how this thin, waxy cuticle layer changes over time on the mosses. (Make like I am looking at something tiny.)
     That is where I usually start and depending on the person's level of interest or next question, I continue from there.

- I submitted my first manuscript from my dissertation research to a scientific journal. The paper was turned down by the first journal that I sent it to. I might have been shooting a little high by sending it to a flashy journal with a higher impact factor. Then I reformatted and sent it to a different journal and am waiting to hear if they will send it out for review. Fingers crossed.

- I have been working with a undergraduate student squashing moss tissues to try and count chromosomes. The squashing and staining parts are working well. Now we just need to catch them at just the right developmental stage.

- We (a group project for the Funariaceae grant) have the first color proof of our Brochure focusing on mosses in Connecticut and using them to teach biological concepts to high school students. Stay tuned for a link to the brochure online or where to order. It is almost ready!

- I reviewed a manuscript focusing on bryophytes for a peer-reviewed (me being the peer) science research journal.

And a mossy photo from Malaysia to end the post.

Berry Go Round #32

The September edition of the plant carnival Berry Go Round has been posted at A Blog Around the Clock.  Enjoy the fabulous flora!

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

A Tale of the Sphagnums that Weren't

There are over 350 different species of peat moss in the genus Sphagnum. All of them have a similar morphology with two different types of cells that make up their leaves. Large cells that are dead at maturity and small cells that are alive and contain green chloroplasts. The large hyaline cells have pores that open to the outside of the plant. When they fill with water they enable the plant to function as a sponge and hold up to 20X its dry weight in water. This is the feature that makes Sphagnum peat mosses the most economically important mosses in the world.

Below you can see both the large dead cells and small, green, live cells in a transverse section of a Sphagnum peat moss leaf.

I just finished reading a recent scientific article on peat mosses.

A. Jonathan Shaw, Cymon J. Cox, William R. Buck, Nicolas Devos, Alex M. Buchanan, Lynette Cave, Rodney Seppelt, Blanka Shaw, Juan Larraín, Richard Andrus, Johann Greilhuber and Eva M. Temsch. 2010. Newly resolved relationships in an early land plant lineage: Bryophyta class Sphagnopsida (peat mosses). American Journal of Botany 97:1511-1531.

These researchers set out to look at the relationships among the many species of Sphagnum peat mosses. Often plants or animals are initially grouped together based on their morphology (how they look on the outside). This has been the case with peat mosses too.  Using DNA sequence data, these scientists determined that some species traditionally placed in the genus Sphagnum really fall outside of this group. Since they no longer lie within Sphagnum they needed some new names.

One was given a new genus name (from Sphagnum inretortum to Eosphagnum inretortum) and placed into an already established family (Ambuchananiaceae). The prefix eo- means early or primitive, thus this would be the 'early peat moss'. For the other, both a new genus and family was created for the species (from Sphagnum sericeumm to Flatbergium sericeum in the Flatbergiaceae). I looked through the paper for some insight into the etymology of this name, but I did not think they mentioned anything specific about the naming.

Both still close relatives to their abandoned Sphagnum buddies. I know that the changing of plant and animal names may seem like a pain or trivial, but understanding which species are each others closest relatives is important. For example if you have a food allergy to a particular type of plant it is important to know who its close relatives are, because you might be allergic to them too. Or we might stumble across a new chemical in a plant that could be used in a medicine. Knowing that plant's relatives may help us to find similar kinds of helpful chemicals in other plants. Just something to think about when you hear about scientists changing the names of your favorite plant or animal.

Above is a surface view of the two different types of cells in a Sphagnum leaf.

Berry Go Round #31

The latest edition of the plant carnival Berry Go Round has been posted at Seeds Aside. It is quite an in depth line up and a large number of the posts I had not seen over the past month. Moss Plants made the list near the bottom. August was a little sparse on science posts for me here. Guess I will need to move the blog a little higher on my priority list to get around to some more detailed posts. In the meantime enjoy the carnival!

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

A Mossy Bath Rug

A friend sent me this link to a bath mat made of moss. They don't specify what types of mosses they are using, but it looks to be Hypnum or maybe Thuidium. It would make for a pretty interesting bathroom experiment. Mosses do not require too much light and they love high humidity levels, thus the bathroom sounds like the perfect place.

I do wonder where they are getting the mosses. Wild collected, from a local landscaper, or are they growing them for this particular project?  

My Bryology Bookshelf - VI

Field guides to mosses are not super common. If you are a longtime reader of this blog you are probably familiar with my frustrations that there is not a good field guide to the mosses and other bryophytes of eastern North America. There are highly technical books that require the use of a microscope (Crum and Anderson's Mosses of Eastern North America). One of the non-technical books that I have is Walk Softly Upon the Earth: A Pictorial Field Guide to Missouri Mosses, Liverworts and Lichens, by Lisa Potter Thomas and James R. Jackson. This book includes photographs of each species with a scale bar to help with the sizes of the plants and color illustrations for many. The descriptions have a wealth of information covering the habit, species they might be mistaken for and information on the etymology of the names. 

I found it especially interesting and fun that they start the book in just the same way that I start my presentations about mosses. We both start by going through all the plants that are sometimes called moss or are mistaken for mosses but really are not. There is also a section where they discuss the mythology and lore associated with mosses. Scattered throughout the book are whimsical line drawings of the good fairies from German folklore called Moosweibchen. 

I think that the title of the book is a perspective that all of us can strive to implement in our lives. I thoroughly appreciate the authors cautions about over-collecting plants from the wild. I think that is a point that some books on bryophytes miss.

My Bryology Bookshelf - V

Another book that I picked up recently was a great book of fabulous images from Bill and Nancy Malcolm, entitled The Forest Carpet. This book is from the authors of the spectacular bryophyte glossary. They cover all three lineages of bryophytes (liverworts, mosses and hornworts), one lineage of ferns, a couple of fern allies (aka. fern friends), and lichens. The images are large, filling the pages of this coffee-table sized book. Each image comes with an informative caption, identifying the specific species pictured and notes the magnification. There are photos of the plants growing in their particular habitat, closeups of the exterior of the plants, and some sections showing the interior arrangements of the cells.

The goal of this book is to make people aware of the smaller organisms that make up the green background that covers the forest floor like a carpet in New Zealand, hence the title. I think that this book does a great job of immersing you into this miniature world!

Botanical Images

For the past five years, the Botanical Society of America has sponsored a image competition to fund student travel to the annual conference. It is called the TRIARCH "Botanical Images" Student Travel Award. Out of the 83 images submitted this year, three of the images featured mosses. They are the following images:

#19 showing a mixture of small organisms including mosses, lichens and green algae.
#25 showing a bright yellow slime mold climbing the sporophytes of Dicranum flagellare.
#26 showing a cluster of antheridia in Rhizomnium punctatum.

I really love #25! The title of the image is "Ever Higher" and it is just a great description for thinking of the slime mold climbing the saprophyte stalk. I also think that the color contrast is great between the green sporophyte and the yellow slime mold. 

Botanical Society of America Awards

Thanks to all my great colleagues (EEB Grads, Jones Labmates & Goffinet Labmates) who helped me get my talk ready for the national meeting. I totally appreciate all the help and support!

Berry Go Round #30

The latest edition of the plant carnival Berry Go Round has been posted at Brainripples. I was off in Providence, Rhode Island this week attending the Botanical Society of America annual conference. Today I am back in the office but I am in need of some decompression before diving back into my research, so I think that I will spend the day enjoying the Berry Go Round carnival and will get back to work full-tilt tomorrow. I listened to some great presentations and heard about a lot of cool research. A good portion of it was bryology related and I will look through my notes over the next couple of days to find some fun stories to share here on the blog. 

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

The Moss Videos of the Moment

Apologies, the blog took a bit of a summer vacation while I focused on writing up the first chapter of my PhD dissertation. It reminded me of the hiatus the Puzzler takes on the NPR program Car Talk. It may be a slow transition back to posting often, but I am going to start by shooting for once a week.

The latest news in the moss world has been the publication of an article in Science magazine on the explosive vortex caused by Sphagnum capsules opening. It is the same opening mechanism that I discussed in a post back in April

If you prefer to listen to the news, you can hear more about this study on the Science Magazine Podcast for 23 July 2010. The piece on Sphagnum runs from 12:52 to 20:50 in this episode.

You can tell it is the talk of the town, because all sorts of outlets have been posting about it. They feature it over here at the International Association of Bryologists blog and at Wired Science and on Discover Magazine and the New York Times and at ScienceNews, so you get the idea. This is the hot moss story of the moment. So if you have yet to hear the full story and see the great videos check out some of the links above

Berry Go Round #29

The latest edition of the plant carnival Berry Go Round has been posted at the Agricultural Biodiversity Weblog. Enjoy the plants of summer!   

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

Moss Workshop and Walk

The announcement is up for my next moss walk this summer through the Connecticut Botanical Society. The details are listed below or you can check out the information here on their website.

 Moss Workshop and Walk - July 24, 2010 (Saturday 1:00 to 4:00 p.m.)
Hiding beneath your feet are an array of bright green plants, just waiting to be discovered. Come explore the trails and lake-shore of the James L. Goodwin State Forest in Hampton, Connecticut with Jessica Budke, a PhD student studying mosses at the University of Connecticut. After a brief indoor introduction we will head outside to identify and experience a diversity of mosses that are common in Connecticut forests. Participants should wear sturdy shoes and dress for the weather. 

(Update  2 July 2010 - The Workshop is currently full. If you would like to be placed on the wait list feel free to contact me.)  

Registration:This workshop is open to the public and is limited to 14 people. Call or email Jessica Budke ( to register - (860) 486-6306. Directions will be sent to registrants.

Berry Go Round #28

The latest edition of the plant carnival Berry Go Round has been posted at Greg Laden's blog. This month there is a lot of interesting items to read about non-mossy-plants. Enjoy!   

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

Hornworts, A Separate Group?

A few weeks back (My Bryology Bookshelf III) I had a question about when hornworts were moved from being recognized as a type of liverwort to their own independent lineage. I put this question to my lab-mate Juan Carlos and he came up with this response.

Since the flat thalloid gametophyte looks quite similar between hornworts and some liverworts, they were thought to be to be a type of liverwort. They were definitely thought to be unique due to their sporophyte. Hornwort sporophytes grow from the base and open by two longitudinal slits that start from the top and move toward the bottom. The spores line the entire length of the interior of the sporophyte. Whereas liverwort sporophytes consist of a spore filled capsule atop a thin translucent stalk.

One of the first researchers to publicly recognize the hornworts as their own phylum (Anthocerotophyta) was Rothmaler in 1951. So there's the answer to my question. When were hornworts recognized as a separate lineage?

For more information on hornwort classification check out this scientific article.
Raymond E. Stotler and Barbara Crandall-Stotler. 2005. A Revised Classification of the Anthocerotophyta and a Checklist of the Hornworts of North America, North of Mexico. The Bryologist 108:16-26.

My Bryology Bookshelf IV

I led a moss walk several weeks back. On that outing I heard about a book that includes some bryophyte identification that I had not seen before. It is A Golden Guide: Non-Flowering Plants by F. S. Shuttleworth and H. S. Zim. It is an older book, with the latest edition having been published in 1967, and is out of print. I found a used edition online. It covers a broad array of organisms, including Algae, Fungi, Lichens, Mosses, Liverworts, Hornworts, Ferns, and Gymnosperms.

The book describes 34 different mosses, 12 liverworts and one hornwort. There is a short introduction to mosses that includes information on their life cycle and basic morphology. The guide includes small color illustrations. They don't give too much detail but do give you a general sense of the morphology of the plants. Each moss has a short sentence about the habitat, some information about the species morphology and then some numbers to indicate the general size of the plants.

My main critique is that a majority of the bryophytes in the book do not have their scientific names listed. They only have a common name. Contrary to other scientists I know, I like to use common names when teaching mosses to the public. However I always use them in conjunction with the scientific name. Common names can vary depending on the area of the country you are in or which language you speak. Scientific names are all in latin and thus have stability no matter where you are or what language you speak. They are critical to be sure that everyone is communicating about the same type of plant. From the descriptions, some of the genera are easy enough to identify but others may take a little more effort to identify. 

If you are looking for a bryophyte guide, I don't think that it is the first book that I would buy. However if you already have quite a few books it might be another interesting one to add to your collection.

Berry Go Round #27

The latest edition of the plant carnival Berry Go Round has been posted at A Neotropical Savanna. This month there is a featured post about mosses from Justin Thomas at The Vasculum. He features a number of different mosses including a few in the Funariaceae (Funaria hygrometrica and Physcomitrium pyriforme to be specific). This is the moss family that I study. He has some really sharp photos and includes nice descriptions to help you identify the species. The rest of the posts focus on flowering plants, but despite their non-mossy-ness they have some great botanical information to share. Enjoy!      

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

My Bryology Bookshelf - III

Mosses With A Hand Lens by A. J. Grout 
Third Edition - 1924
A Popular Guide to the Common or Conspicuous Mosses and Liverworts of the North-Eastern United States

In my search for a field guide to the mosses of New England, I came across this book at my university library. I then purchased my own copy to add to my reference shelf. You can check out the entire book here online at GoogleBooks.

Some great aspects of this book are that it is meant to be used with a hand lens. Other books require either a dissecting or compound microscope. The initial dichotomous key is a manageable length with 25 couplets. Then it spits into Acrocarpous and Pleurocarpous mosses that then have a 36 and 14 couplet key respectively. The line drawings are really well done and are quite informative for species identification. The photographs are ok, especially considering they are from 1924, but are pretty grainy and black & white. The diagrams for the liverworts are typically much smaller and with less detail. This may show a bias of the author toward the mosses.

Since the book is quite old some of the names of the genera are out of date. But it is interesting historically to see how the scientific names have changed from then to now.
Catharinea is now Atrichum
Webera is now Diphyscium
Georgia is now Tetraphis

Another interesting finding in this book is that hornworts are described as a specific type of liverwort. They are classified in the family Anthocerotaceae, The Horned Liverworts. Currently the hornworts are classified as a distinct lineage separate from the liverworts. Thus there are three main groups of Bryophytes; Mosses, Liverworts and Hornworts. I am not sure when hornworts were moved to their own lineage. Sometime between 1924 and now? This is a question for my lab-mate Juan Carlos. I will let you know what he says when I see him tomorrow.   

Timmia megapolitana

Here are some photos of the moss Timmia megapolitana, the species that I worked on for my Master's Thesis.  Its common name is the Indian Feather Moss, due to the calyptra that remains atop the sporophyte capsule, sticking up like a feather. (It really isn't a very politically correct common name. Maybe we could come up with something better. How about the Periscope Moss? Any other ideas?)

Anyway these are some photos that I took of the plants and my fieldsite out in Albany, New York. This was several years back and before I owned a digital camera. Thus the images are a little rough, since they are scans of prints. This species grows on calcium rich substrates. This area has a lot of limestone. The mosses grew on the sides of fissures in the rock (below right) or on the sides of small ledges (below left). I also found this species growing at an abandoned marble quarry in Vermont, another substrate that has a basic pH and is calcium rich. 

Lamellae Story Debunked

I have been relaying the science tale of lamellae as snorkels for quite a while now (here and here on this blog) and I recently came across some scientific literature that completely debunks that idea. Honestly I am not sure if I read about the snorkel idea somewhere or if it just emerged as common knowledge from taking classes and reading. Sometimes there are just "factoids" that exist our heads and we may not know where they came from. As a scientist I totally should have been more careful about the source of my information prior to relaying in the public sphere on this blog. Despite this embarrassing misleading information, I would like to offer a correction via this post.

The dilemma is that mosses and other bryophytes typically interact with water and air differently than other plants. Vascular plants have roots and internal plumbing (xylem cells) that move water into their body and they take gasses in via stomata, small openings in the leaf surface. Bryophytes on the other hand do not have roots or xylem cells to move the water, they absorb water directly through their entire plant body. They also do not have stomata on the gametophyte plant and thus take up gasses across their entire plant body, too.

Think of having to both drink and breath through your skin at the same time. The parts that are taking up water can't exchange gasses and the parts exchanging gasses can't take up water. So, what's a bryophyte to do?

Well Polytrichum has solved this dilemma using its lamellae. They are the green filaments of cells (see above) on the upper surface of the leaf. They are not acting as snorkels. Instead they are creating spaces for small pockets of air between the lamellae for gas exchange. The air spaces do not become filled by water due to a waxy cuticle that covers the epidermis and the cells at the tips of the lamellae. In Polytrichum water is acquired via internal conduction through the stem of the leafy gametophyte. This internal plumbing is not very advanced, but you can see some of the small conducting cells in the center of this cross-section through the stem of the leafy gametophyte. This plumbing continues into the leaves. 

So that is a bit about our current level of understanding when it comes to lamellae on Polytrichum leaves. Once again I apologize for any confusion I may have caused. It just goes to show that it is important to cite your sources and to double check the knowledge in your head every once in a while.

The papers that I consulted for writing up this explanation are listed below.

Sphagnum capsules

Sphagnum mosses (peat mosses) have a capsule with a really interesting manner of spore release. They open with an explosive *pop* that can be heard when this moss is close by. The mechanism by which this occurs has been described as internal air pressure building up as the capsules dry, shooting the lid off the top. This is the only type of moss that has an explosive opening, thus it has attracted some interest.

In lab group we recently read a paper that explored this mechanism to try to figure out the processes involved in their explosive opening.

In the above research study, they carried out a seemingly obvious, but previously unexamined experiment. They poked holes in the capsules, dried them out and then observed how many of the capsules opened explosively. With holes in the capsule air pressure should not be able to build up inside and you would predict that the lid would not pop off.

Despite poking holes in the capsules the lids still popped off. So the explosive nature is probably not due to a buildup of pressure. The researchers propose that the mechanism to explode off the lid is due to shrinkage of the capsule walls. The side walls of the capsule buckle in and the rigid lid (operculum) flies off.

I think that it is super cool when simple experiments can be used to test seemingly established biological ideas. It is even more fun when the results turn the established idea upside down. Boy, science is cool! 

Berry Go Round #26

The latest edition of the plant carnival Berry Go Round has been posted at Gravity's Rainbow. The theme for this edition is springtime. We have been experiencing a lot of those spring showers here in Connecticut lately. I am most definitely ready for some sunny spring weather for a change. But in the meantime check out the spring-spirit at the carnival. One of my posts from this past month was featured in the lineup. It is the post about the number of moss species worldwide.  

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

Sporophytes of the Liverwort Aneura

 A few weeks back I took these photos of some liverworts in the genus Aneura. They are of the diploid sporophytes (two sets of chromosomes per cell). At maturity the ball shaped capsule is rapidly elevated on a thin, thread-like stalk. The capsule opens via four vertical sits to expose and disperse the spores within.

 When the capsule is immature and before the stalk has elongated the sporophytes look like these two images below. The capsules are the darkened areas at the tips.

An interesting aspect is that the stalk elongates quickly. Unlike mosses the stalk of the liverwort sporophyte does not become longer from cell divisions. It becomes longer by all the cells in the stalk expanding and elongating by increasing the liquid inside of their cells. That is why the cells of the stalk are clear. They are stretched very thin. Keep your eyes peeled for this type of sporophyte. This morphology is a key feature for identifying a liverwort.

Connecticut Botanical Society Workshop

Saturday April 17, 2010 - 9:30am-12:30pm
Nature Center, 269 Oak Grove Street, Manchester, CT

I will be leading this workshop sponsored by the Connecticut Botanical Society next month. It is free and open to the public. Space is limited to 14 people, so if you are interested in attending please contact me.

Have you every walked through the woods to observe a carpet of mosses? Upon closer inspection you notice that there are a wide variety of patterns, shapes, and colors within such a small amount of space. In this session you will learn how to indentify and explore mosses. This introduction to mosses will be based upon properties that can be observed with a hand lens. Participants should wear sturdy shoes and dress for the weather. After the indoor introduction we will car pool to the field site (Bolton Notch State Park).  Coffee and light refreshments will be available at the start of the workshop.

Call or email Jessica Budke to register -  (860) 486-6306 

(Update 10 April 2010 - The Workshop is currently full. If you would like to be placed on the wait list feel free to contact me.)

My Bryology Bookshelf - II

Another book on my shelf is Gardening with Moss by F. F. Rockwell. I am not sure when I picked up this book, but there it was hiding on the shelf and I decided to give it another look...

And now I remember why I cannot recall when I picked up this book. The title is quite deceiving! You might think that it is another book about growing mosses in your garden similar to these two (here and here) that I have discussed before. But no, this book was written in the 1920's and the title should be 'How to use Peat Moss (Sphagnum) when Gardening Flowering Plants'. It is interesting as a historic text. The first chapter is all about peat moss and its utility in the garden. This chapter also features a nice story about the author's first meeting with peat moss. From what I can tell the rest of the book does have sound gardening advice, but it is probably the same information that you could get from a more recent book.

Overall I wouldn't recommend it if you are looking for a book on Moss Gardening, but as a history or gardening buff it might prove interesting. You can check out a limited preview of the book here at GoogleBooks.  


You probably have not heard of this moss before. It it pretty rare and I actually don't know anyone who has seen them in the wild. There are only two species in the genus (Takakia ceratophylla and T. lepidozioides). The genus is native to western North America and a few locations in Asia. 

This moss has an interesting naming history. It was originally discovered with only green, photosynthetic gametophytes. As you can see from the photo at left the leaves are deeply lobed and filamentous. Initially, the gametophyte was identified and named in the liverwort genus, Lepidozia. It wasn't until almost 100 years later that Takakia was found with sporophytes. The sporophytes have a persistent and tough seta/stalk with a capsule that opens via a single curved slit. If it was really a liverwort the stalk would be thin, translucent and ephemeral with a capsule that opens by 4 longitudinal slits. Once the sporophytes were found these species were moved into the genus Takakia and they have been hereafter identified as mosses.

Pretty amazing that it took that long for scientists to discover the sporophytes and then to figure out that they are really mosses.


My Bryology Bookshelf - I

I recently started a list of recommended bryology books on my sidebar. However I wasn't sure how many of these books I had talked about in actual blog posts. So I decided to start up a group of posts that walk through the bryology books on my shelf.

I also wrote about the fabulous bryophyte dictionary, Mosses and Other Bryophytes, an Illustrated Glossary by Bill and Nancy Malcolm.

One of the books on my list that I have yet to talk about is my advisor's most recent book Introduction to Bryophytes by Alain Vanderpoorten and Bernard Goffinet.

When I helped teach and Undergraduate Course in Bryology a few years back we could have really used this text. We used some excerpts from the book Bryophyte Biology. I think that this is a great book too. Unfortunately it is pretty tough for the average undergraduate. Bryophyte Biology is geared more for a graduate student or professional audience.

I have yet to use the new book Introduction to Bryophytes to teach, but I think that it will work really well for that purpose. It is aimed at undergraduate biology students or science savvy amateurs. I have also used the book to hunt up some fun bryology facts for use during my moss walks. If you want to really dig into all the different types of bryophytes and their morphology then this is probably not the text for that endeavor. However it is a look at the biology of bryophytes from a number of different angles, such as Physiology, Conservation, Ecology, Biogeography and Evolution. 

Berry Go Round #25

The latest edition of the plant carnival Berry Go Round has been posted at Foothills Fancies. Since it is the February edition there is a fun chocolate-y theme throughout. Beware of reading if you have a sweet tooth or if it is before lunch. I almost decided to have a chocolate dessert before my lunch when I read the carnival this morning. 

One of my posts from this past month has been included in the lineup! It is the post where I discuss a new moss gardening book. BGR also mentioned that I recommended checking out the moss-cam. I have heard about the moss camera project that is run by researchers out in California, but I have not discussed it on my blog, nor do I have a link to it anywhere that I can see. I think that the credit for mentioning/blogging about the moss-cam should go to Dr. Lalita Calabria who has recently started a blog called "Adventures of a Phytochemist".  She has an extensive post about mosses and I think that might explain the confusion.

For more about blog carnivals and my posts about the earlier editions of Berry Go Round, click here.

How many mosses are there?

One of my bryology students told me that their friend could not believe that they were taking a course on mosses. Their friend's comment was that there is only one type of moss, right? The small green kind.

This question boggles my mind. Is there only one kind of bird? No. One kind of tree? No. One kind of moss? No. You have to get pretty specific in your definition of any living plant or animal before the answer to that type of question is yes. For example, is there only one kind of ostrich? Yes. Only one sugar maple tree? Yes. You get the idea.

So my point is there are many different types/species of mosses in the world. Just take a look at some patches of moss when you are out and about. I bet that when you get close to the mosses and really peer at them you will notice that the first patch does not look exactly the same as the the second patch.

The question that I more often get but have a hard time answering is, "How many species of mosses are there worldwide?". This presents a problem, because it depends on who you ask and whether they are a splitter or a lumper. (Basically - A splitter is a scientist who tends to find differences between organisms and then groups them in a way that creates more species. A lumper is a scientist who would look at the same organisms focus on the the similarities and then group them in a way that creates fewer or one species.) Those are not technical biology terms and these are my own informal definitions, but if you were to use either of them with a biologist who thinks about species they will most likely know what you mean.

In the end this makes for a difficult question  "How many species of mosses are there worldwide?" I have looked through a number of bryology and botany books on my shelves and here is the range of answers to this question. (The quotations are arranged in chronological order.)

Bryophyta by Parihar (1961) p.150 "... about 660 genera and 14,500 species."
The Structure and Life of Bryophytes by Watson (1971) p.16 "Some 14,000 species of moss are known and the great majority are sufficiently alike in structure to create a real difficulty for the taxonomist."
Biology of Plants by Raven, Evert and Eichhorn (1999) p.412  " least 9500 species of mosses, with new forms being discovered constantly, especially in the tropics."  

A Checklist of the Mosses by Crosby, Magill, Allen, and He (1999) p.1 "This Checklist recognizes 12,754 species. Although new species of mosses continue to be described, the number being recognized appears to be declining, because of increased synonomy."

Introduction to Bryology by Schofield (2001) p.10 "... contains approximately 10,000 species in nearly 700 genera."

Bryophyte Biology edited by Goffinet and Shaw (2009) Ch. 2 p.56 "With approximately 13,000 species, the Bryophyta compose the second most diverse phylum of land plants."

Introduction to Bryophytes by Vanderpoorten and Goffinet (2009) p.70 "Approximately 12,000 species are currently recognized,..."

From this survey we end up with an answer that ranges from 9500-14500 species of mosses. Scientists are usually comfortable with a high level of uncertainty so they may find that range a sufficient answer. Remember it's not as though there is a right answer and by giving a range scientists just don't know. The number of species is constantly changing as new ones are discovered and others may go extinct. It also depends on which expert you consult (splitter or lumper). So the answer to this question is in a constant state of fluctuation. 

I find that giving a single number is more satisfying if I do not want to go in the the whole explanation that I have given here. Usually I say that there are approximately 12,500 species of mosses and I quote A Checklist of the Mosses as my source. This count is going on ten years old at this point, but I think that it is the most accurate count that we currently have. It also looks like the two books from 2009 are following this count as well with their values that are a little above and below those of the checklist.

So, "How many species of mosses are there worldwide?" you may ask.

To that I would answer that there are approximately 12,500 (Crosby et al 1999).

Preview of the Book "Nesting Season" at Northern Woodlands Magazine

A few of the nests featured in this article appear to include mosses as part of their construction materials. At least that's what it looks like from the photos and drawings.
I wonder how many different species of birds use mosses to build their nests?

Moss Cell Walls Like Sponges

I came across this paper when cleaning off my computer desktop today. My labmate Juan Carlos sent it to me a while back. Upon stumbling across it again I decided to give it another read.

H. G. Edelmann, C. Neinhuis, M. Jarvis, B. Evans, E. Fischer and W. Barthlott. 1998. Ultrastructure and chemistry of the cell wall of the moss Rhacocarpus purpurascens (Rhacocarpaceae): a puzzling architecture among plants. Planta 206:315-321.

This paper focuses on the unique cell walls of leafy gametophyte of this moss. (For a little review of plant cell walls check out last week's post.) Rhacocarpus purpurascens grows in the high mountains of some tropical areas. It grows in large sheets that hang from rock faces and they pick up most of their water from fog. It has been known since the 1970's that the cell walls of this plant are structurally sponge-like. (Think your morning english muffin with a lot of nooks and crannies.) Typical plant cell walls are solid. This study sets out to analyze the walls using a number of methods.

They use some high-tech techniques such as electron microscopy (scanning and transmission), nuclear magnetic resonance (NMR) spectroscopy, and cell wall fractionation. Fancy techniques such as these are great. I use both types of electron microscopy in my own research. However I also enjoy techniques that have an elegant simplicity, which is how I would describe the two other experimental methods that they use (external water conduction and water-holding capacity). Basically these methods allow the authors to ask two questions: Can these sponge-like cell walls conduct water up the moss plant? and How absorptive are these cell walls? In these two experiments they compared Rhacocarpus purpurascens to two or three other moss species that have solid cell walls.

For external water conduction the placed the bottom end of the moss stem into a tube of water and measured how far up the stem the water traveled. They found that the water did not move very far up the stem in Rhacocarpus purpurascens, whereas the other species became hydrated all the way to the tip. Thus the cell walls are not functioning in water conduction.

For water holding capacity plants were dried, soaked in water for 10 minutes and then weighed. Contrary to what you might have anticipated, Rhacocarpus purpurascens held 25% less water than the other species per gram of dry weight. (So it does not appear to be acting as a sponge, which was my initial thought when reading the paper.) However a majority of the water that this plant has access to is in the form of fog. It is not submerged when growing in its native habitat. The authors anticipate that the wall characteristics allow the available moisture to be absorbed quickly and moved inside the cell.

I think that it is pretty cool when scientific questions can be asked and answered using simple techniques. It just goes to show that scientific experimentation is accessible to more than university researchers.

Latest Moss Gardening Book

I'd like to introduce you to my latest book purchase. Native Ferns, Moss, and Grasses: From Emerald Carpet to Amber Wave, Serene and Sensuous Plants for the Garden by William Cullina of the New England Wild Flower Society.

If you are interested in gardening with mosses I think that this book would be a great addition to your bookshelf. A limited preview edition is also available through GoogleBooks. The suggestions that he gives are highly detailed including sections on: Choosing a Site, Site Preparation, Transplanting Moss, Blending Moss, Establishing Moss on Rocks, and Maintenance. I found his explanations clear and his text easy to read. I think that he covers all the steps needed to successfully maintain a moss garden. I was a little disappointed that only 13 moss species are covered. The book is heavier on the fern and grasses. The mosses that are included are rated from easy to difficult in terms of their ease to grow, which will help to point you in the right direction depending on your moss gardening skill.

I am happy to report that I am not lodging my biggest complaint about moss gardening books when it comes to this text. Often they skip over discussions of conservation, wild-collection vs. greenhouse grown, and sustainable harvesting. Not this book. These environmentally conscious threads are woven throughout the text. The author works for a top notch conservation group, so I guess his including these topics is not too surprising. It is just one of the things that I look for when reading and evaluating gardening books. Happy reading!

Moss Protonema and Lead

This week in Bryology Lab group I presented a scientific journal article about lead and mosses. It was a pretty interesting read. You may know that some heavy metals (ex. lead and mercury) are toxic. Think kids eating contaminated lead paint. It is bad for them and will make them sick. Well plants are the same way. If too many heavy metals get inside their cells they can damage the plant and make it sick.

One way that plants prevent heavy metals from entering their cells are by binding up the heavy metals before they make it inside. How do they do that you might ask? Well it is a pretty ingenious system. It has to do with their cell walls. Okay a little review. All cells are basically a sac (a bi-lipid membrane sac) filled with mainly water and other neat cell innards. Vertebrate animals give their cellular bodies structure with internal bones, insects have an tough exoskeleton that gives them shape, and plants have cell walls that help to keep them upright. Each of their cells is surrounded on all sides by these rigid cell walls that are connected together across the entire plant body. Without the cell walls plants would be a floppy mess.

Back to the connection with lead. The researchers determined that the moss plants, particularly at the protonema (filamentous) stage bound the lead to their cell walls so that it would not enter the cells. When placed in a lead bath they could even change the chemical composition of their cell walls to bind up (sequester) even more of the lead. This method does not keep all of the lead out of their cells but it is a good start. This phenomenon has been observed in the roots and pollen tubes of other plants. Boy plants are awesome!

Click on the citation below for a link to the paper.

Mosses in Malaysia

Well I sure had a whirl-wind adventure traveling around southeast asia for 2.5 weeks. The itenary was as follows. I flew from New York to Kuala Lumpur, Kuala Lumpur to northern Borneo (then back), Kuala Lumpur to Java (then back), I stayed put in Kuala Lumpur for a few days, and then home to Connecticut.

My favorite part of the trip was Northern Borneo. We were in Sabah, Malaysia near the town of Sandakan. We roomed at the Sepilok Jungle Resort, and I thought that it was a nice place to stay despite the poor review it was given in the most recent Lonely Planet Malaysia. We visited the Sepilok Orangutan Rehabilitation Center and the Rainforest Discovery Centre, both within walking distance of our lodging. With the rainy season upon us, we didn't get to explore aroung the rainforest nearly as much as I would have liked. Here are some of the mossy photos from the adventures.

All available surfaces were covered in mosses including tree trunks, fallen logs and hanging vines.

Here we have some mosses in the Calymperaceae. They are a very common family in the Pacific Tropics. Their identifying feature are the clusters of gemmae at the tips of the leaves.

 Some tiny critters like this ant were hiding among the mossy cover.

A few of the species that I saw had some tiny sporophytes rising above the leafy gametophytes.