Sunday, March 30, 2014

Talk at Botany 2014

I will be giving a talk at the Botany 2014 conference this summer, which be held from July 26-30 in Boise, Idaho. I'll be talking about the fern mating system survey I've been posting about here for the last few months, which is a collaborative project with Weston Testo at the University of Vermont, and Rehman Momin and Eddie Watkins at Colgate University. You can check out our abstract here, and come to the talk if you're attending the conference! As usual, it looks like the Pteridological Section talks will be the absolute highlight of the week.

Tuesday, March 25, 2014

A slew of fern gametophytes

Our spore growing efforts are really paying off! The species we're growing are from a variety of sources, including the Royal Botanic Garden Edinburgh, the greenhouses at Colgate University, and the Duke University herbarium. The latter have proven a little challenging – it's difficult to collect viable spores from herbarium sheets! But we're having success with a number of species in many different families, and it's very interesting to see their various morphologies and growth rates. Quite a few have produced eggs and sperm, found mates (not hard on the crowded petri plates) and made new sporophytes. For the actual experiments, we're moving them to separate plates long before they develop reproductive capacity, so that we can determine whether they're able to self or must have another gametophyte to mate with.

Have a look at some of what we've got growing:
Ceratopteris richardii
Davallia pentaphylla
Davallia pentaphylla
Notholaena californica, already producing farina in the gametophytes and young sporophytes
Notholaena californica 
Pellaea sp., hard to see the gametophytes because of the little sporophytes!
Pityrogramma calomelanos 
Thelypteris sp., with healthy young sporophytes

Sunday, March 23, 2014

180 million year old fern fossil discovered

Photo from the Science paper, credit: Benjamin Bomfleur
Several Swedish biologists (from Lund University and the Swedish Museum of Natural History) have published a paper in Science documenting an exquisitely preserved, 180 million year old fern fossil! The Jurassic-era fossil is a member of the family Osmundaceae, which includes modern taxa like cinnamon fern (Osmundastrm cinnamomea), royal fern (Osmunda regalis), and interrupted fern (Osmunda claytoniana), all of which are widespread in the temperate northern hemisphere (and are pictured below). The fossil's exquisite preservation is attributed to rapid burial during volcanic activity.

It has long been known that modern members of Osmundales don't vary much morphologically compared to ancient forms – fossilized members of the order dating to the early Mesozoic (ca. 220 million years ago) are remarkably similar in several aspects of their morphology to modern species. The new fossil goes a step further: it contains intact cells, and even individual chromosomes, that the researchers were able to visualize with various types of microscopy. The fossil species had the same number of chromosomes and roughly the same predicted DNA content in the nucleus as modern cinnamon fern. This suggests that the lineage has not experienced significant upheaval in DNA content, through whole-genome duplication (polyploidy) or extensive gene loss, in the last 180 million years. The authors note that to date, most of what we know about ancient fern genome size is due to extrapolation from living taxa; this new fossil has permitted the first direct observations of paleo-DNA content in a fern.

Coverage of the new fossil online:
From Lund University

The paper (requires a subscription): Bomfleur, B., S. McLoughlin, and V. Vajda. 2014. Fossilized nuclei and chromosomes reveal 180 million years of genomic stasis in royal ferns. Science 343: 1376–1377.

If you want to read more about relationships of Osmundales (also requires a subscription): Metzgar, J.S., J.E. Skog, E.A. Zimmer, and K.M. Pryer. 2008. The paraphyly of Osmunda is confirmed by phylogenetic analyses of seven plastid loci. Systematic Botany 33: 31-36.

Osmundastrum cinnamomea 
Osmunda regalis
Osmunda claytoniana

Saturday, March 15, 2014

UF campus plants, part V

More photos from walks around the UF campus with Walt Judd (see part I for more information). This walk was on March 13, 2014 at UF's Natural Area Teaching Lab.
Acer negundo
Quercus nigra
Acer negundo
Thelypteris sp.
Rumex crispus
Rumex crispus
Prunus caroliniana
Pinus sp. 
Rubus trivialis
Stachys floridana
Tradescantia ohioensis

Sunday, March 9, 2014

Trip to Helsinki, Finland

Kaisaniemi Botanic Garden at Luomos, the Finnish Museum of Natural History
I've just returned from Helsinki! It's a beautiful city, even in wintry March, and I had a great time working with fern colleagues at the Finnish Museum of Natural History. Aino Juslén and Henry Väre were my hosts, and we have some big projects on Dryopteris, among other things, planned together. We had never met before, despite having co-authored a paper, so it was wonderful to spend a whole week with them. We poured over herbarium specimens they had received on loan from Kew, Berlin, and Stockholm, as well as Helsinki's own great collections, I gave a talk on reticulate evolution in ferns, and we ate some delicious food. I thought I'd share some photos reflecting most of these activities, as well as Helsinki itself.

The entrance to the herbarium
Beautiful wooden cabinets 

Carvings on each of the doors (not necessarily representative of the plants inside...)
Henry, Aino, and me
Sorry vegetarians, but there were lots of delicious sausages to be had...

A sunny day!
Main University of Helsinki building
Finnish Museum of Natural History
Finnish National Theater
Senate Square
Helsinki Cathedral
Statue of Alexander II, who established the Diet of Finland in 1863.