September 6, 2011

Know Your Biomes IX: Chaparral

Fynbos in the Western Cape, South Africa*
As much as any biome or global ecoregion is a challenge to group, differentiate or otherwise generalize, the chaparral or Mediterranean woodlands (scrubland/heathland/grassland) biome may be the best example such classification difficulties. There’s perhaps more general agreement regarding the features of this biome, even if the name tends to change from author to author. Many texts will not even include this biome in their list of major regions, instead making a small reference to it in the section regarding deserts. However, these areas, considering their combined territory, contain about 20 percent of the world’s species of plants, many of them endemic gems found nowhere else. On the flipside, due to the often environmentally heterogeneous nature of this biome, organisms that are prominent, integral members of other biome classifications are found in the chaparral as well. For the sake of consistency in this post, I’ll continue to refer to this biome as chaparral, as incomplete a descriptive designation as that may be.

Specifically, chaparral biomes exist in five major regions: South Africa, South/Southwest Australia, Southwestern California/Mexico, Central Chile and in patches wrapped around the Mediterranean Sea, including Southern Europe and Northern Africa. These regions are unified by their hot, dry summers and mild winters, referred to as an archetypal Mediterranean climate at 40 degrees north and south approximately.

The vast majority of rainfall usually comes with the cold fronts of winter. Annually, chaparral can experience anywhere from 250 mm of rain all the way up to 3000 mm in isolated subregions like the west portion of Fynbos in South Africa.

Plants in chaparral areas tend to be sclerophyllous (Greek: “hard-leaved”), meaning the leaves are evergreen, tough and waxy. This adaptation allows plants to conserve water in an area where rainfall is discontinuous, but probably evolved to compensate for the low levels of phosphorous in ancient weathered soils, particularly in Australia where there have been relatively few volcanic events to reestablish nutrients over millions of years. Obviously, these plants also happen to do very well during the xeric summers of the chaparral where drought is always a threat.

Because of the aridity and heat, the chaparral plant communities are adapted to and often strategically dependent on fire. Evolutionary succession scenarios constructed by scientists typically point to fire as one of the major factors that created much of chaparral areas in Australia and South Africa from Gondwanaland rainforest. (Fire ecology really deserves at least a post of its own, which I’d like to discuss given the time in the future.)

Some of the regions in the chaparral are exceptional. In South Africa, the area known as the Fynbos constitutes its own floristic region (phytochorion) among phytogeographers, the Cape Floristic Region. While it is the smallest of these floral kingdoms, it contains some 8500 species of vascular plants, 70 percent of which are endemic. The March rose (Oromthamnus zeyheri) is one of the standout specimens of the group as well as the national flower of South Africa, the King protea (Protea cynaroides). P. cynaroides is a “resprouter” in its fire-prone habitat, growing from embedded buds in a subterranean, burl-like structure. Another endemic species, the Cape sugarbird, is shown feeding on a King protea below**.

There is one unique threat to the chaparral: anthropogenic fire. In the past, if nature had not provided a fire to burn back the accumulated brush in these areas, often the native peoples would do so, and generally speaking, the fires seemed to be controlled and effective. But increased frequency of fires due to negligence or downed power lines can potentially cause catastrophic, unrecoverable fire. Only so much tolerance to such a destructive force can be built by evolutionary processes.

*Image by Chris Eason
**Image by Derek Keats

September 5, 2011

The new Encyclopedia of Life: Collections

I have to admit, I didn't use the Encyclopedia of Life very frequently in its first incarnation. I perused for media every now and then, or doubled checked the taxonomy for a species, but it was not a touchstone for research. The relaunch, however, gives users new functionality to make the experience more organized for personal and community use.

Like any good application, the startup/front page gives you just about everything you need. The mission statement is obvious, the search field is huge and the row of images tells you exactly what your searches will bring. The main site elements are listed below along with FAQ links, newsfeed tells you this is a busy place full of lots of other people. Facebook, Twitter, Tumblr, Flickr; Impression made. It's all familiar, accessible.

The main piece that I've grown to love is the collections. After you've created your account and start searching around for cute pictures of red pandas, you'll notice an Add to Collection button in the top right-hand corner of the page. Clicking the button displays a popup. Follow the prompts to create a new collection.

Collections allow you to create groups of organisms in EOL. Collections can be as subjective or scientific as you wish. Red panda could be included in a collection of the "Cutest Animals Ever" or a more natural category, maybe "Mammals of China." Once it's created, you can search for and add as many inhabitants of EOL as you wish by clicking the Add to Collection button and selecting one (or more) of your collections in the list. For the Cutest Animals Ever collection, you might want to add the echidna or the wolf spider. For the Mammals of China, you might want to add that other panda, whatever its name is.

I started a collection of monotypic taxa from the red panda, the sole species in the genus Ailurus. I searched for other monotypic taxa off the top of my head: the moose, the African civet cat, the Gingko. Then I started getting some responses from the community via the collection newsfeed. Katja said, "Don't forget the Aardvark!" Cyndy said the Western Osprey was a good candidate for the collection. Bob suggested that I add a description so that people visiting my collection knew exactly what "monotypic taxa" are. So I did:

This is how communities can grow out of collections of organisms, communities based on shared interests of one sort or another. In fact, there's functionality there to support those communities, just click the Create Community button next to your collection, add a description, invite some interested parties and start sharing.

EOL gets me thinking. It started with one of my favorite animals and quickly became a taxonomic scavenger hunt. I started researching: Just how many monotypic taxa are there? Why are they important? What does the classification say about these animals and their evolutionary history? As a writer, the answers become the building blocks for an essay. Usually there's nothing manipulable about those ideas; they spawn from reading papers, from the ideas of others. EOL provides a level of control that allows systems to be constructed that plead for further explanation.

Collection building can create new ideas, but it can also be useful for supplementing existing material. I've written about biomes and ecosystems frequently in the past, and it can be difficult to give readers a good idea of the extent or uniqueness of life in a particular region. I'm thinking about using collections in EOL when I can to create lists of organisms that constitute the ecosystem I describe so that readers can browse through the many unique organisms that live there. Excessive listing and description in prose structurally tedious; often its a choice between prose lists and long strings of bullets, which are ugly and usually scary for a casual reader.

EOL suddenly becomes a very interesting resource for science enthusiasts, educators and writers. I have some thoughts about how it could be used in more creative/artistic ways, but I'll hold off for a future post.

Go sign up and play around. It's Labor Day. The grill isn't ready just yet. EOL is a lot of fun.