Moss Tumbleweeds

I just saw this article about mosses living on glaciers in Iceland and the animals living inside them in the New York Times. These balls of moss (glacier mice) are unattached to the ground and can move around the glacier like tumbleweeds. I knew that mosses grow in extreme habitats and even live in Antarctica, but I had not heard about this type of moss growth form before. Pretty cool, moss tumbleweeds!

Coulson, S. and Midgley, N. 2012. The role of glacier mice in the invertebrate colonisation of glacial surfaces: the moss balls of the Falljökull, Iceland. Polar Biology

Glacier Mosses - Fig. 4 from Coulson and Midgley 2012

Other names for these glacier mice are moss balls and rolling moss. This growth form is advantageous for growing on substrates that are unstable like the surface of a glacier or sand dune. 

For some more reading on this type of moss growth form - 

Shacklette, Hansford T. 1966. Unattached Moss Polsters on Amchitka Island, Alaska. The Bryologist 69: 346-352.

Moss Identification Success

Introducing Jaffueliobryum wrightii! Finally I finished up my moss identifications from my field trip to Missouri and Kansas back in March. This is why I don't do much collecting. My collections tend to sit around for quite a while before identifying them makes it to the top of my list of things to do. And unless I have time for identifying them the mosses are best left growing in the wild. 

So Jaffueliobryum wrightii is in the moss family Grimmiaceae. A telling feature is that the leaves have long, white awns at the tips. Thus, I jumped directly to the Grimmiaceae for my identifying. The genus Jaffueliobryum is usually found on calcareous rocks. This population was growing on sandstone. It doesn't really have a common name, but the genus was named for Félix Jafuell, a clergyman who collected plants in South America. There are only 3 species in North America. One only in Mexico and the other two are widely distributed across the western United States. So once I identified it to Jaffueliobryum there were only two species to choose from. The other species, Jaffueliobryum raui, has keeled leaves (the same idea as the keel on a boat, they look folded or have a ridge down the center), which can be easily seen after making a leaf cross-section. Since this sample did not have keeled leaves, it was Jaffueliobryum wrightii.

It was a really fun plant to identify and I'm glad I got the chance to spend some time with it under the microscope. Now off to the herbarium this sample goes.  

    

Identification and species information in this post is from the Bryophyte Flora of North America.  

Mosses produce Scents that Attract

Photo: Erin Shortlidge, Portland State University

I am a little behind in posting about the moss research that came out in the journal Nature a couple of weeks ago. Researchers found that a moss with separate sexes produce volatile compounds (scents) that can attract microinvertebrates, which in turn increases sexual reproduction.

Todd N. Rosenstiel, Erin E. Shortlidge, Andrea N. Melnychenko, James F. Pankow, & Sarah M. Eppley. Sex-specific volatile compounds influence microarthropod-mediated fertilization of moss. Nature. doi: 10.1038/nature11330

 

For some additional science news coverage of the research check out these articles below.

Science News - I really like this article. The journalist did a nice job of contacting other science experts, some of whom I know, to comment on the research.

New York Times - Pretty brief article, but I was glad to see they covered it. 

News Release from Portland State University - All the details and contacts. Also the title is super catchy.

This research connects to and builds on an earlier study that demonstrated that microarthropods increase fertilization rates in mosses. Now there is good evidence that the mosses are attracting the microarthropods to assist in sperm movement

Cronberg, N., R. Natcheva, and K. Hedlund. 2006. Microarthropods Mediate Sperm Transfer in Mosses Science 313: 1255. 

This research is really changing our thoughts on how we think about sexual reproduction in mosses. Animals help to move the sperm around. The plants produce scents to attract them. And even if they do dry out some sperm can survive desiccation (study below).

Shortlidge, E. E., Rosenstiel, T. N. and Eppley, S. M. 2012. Tolerance to environmental desiccation in moss sperm. New Phytologist 194: 741–750.

Overall I think it is really interesting research to read and think about.