« Previous Day: Triteleia ixioides |
Main
| Next Day: Centaurea solstitialis »
Feb 8, 2010: Pandanus tectorius
Feb 8, 2008:
Sclerochiton odoratissimus
Feb 8, 2007:
Hakea epiglottis
Feb 8, 2006:
Eurya japonica
July 15, 2006 : Astragalus racemosus
Interested in subscribing? Visit the main Botany Photo of the Day page and fill out the form in the upper right corner!
Keywords: Fabaceae | Astragalus racemosus Pursh. | Badlands National Park, South Dakota
Today's image is courtesy of Quentin Cronk, director of UBC Botanical Garden. Quentin visited Badlands National Park six weeks ago, and this is one of the images he's chosen to share with us.
With respect to number of species, the genus Astragalus is huge. In fact, it is the largest genus of vascular plants, with over two thousand five hundred species. Even though North America contains over five hundred species, it is not the centre of diversity for the genus – that title belongs to southern Asia. This cream milkvetch is representative of many of the plants in the genus: adapted to live in an arid or semi-arid climate.
Why so many species? The diversity of Astragalus is a result of adaptive radiation, i.e., the rapid speciation of a single or few species into dozens or hundreds of species in a very short time. Other examples of adaptive radiation include stickleback fishes (studied by UBC's honoured evolutionary biologist Dolph Schluter) and the vascular plants known as the Hawaiian silverswords.
For more information on Astragalus, an excellent resource is the The Astragalus Website (the section on biogeography is particularly good).
Posted by Daniel Mosquin at July 15, 2006 12:00 AM
Comments
...or read recent comments on all BPotD Entries
Posted by: Hollis at July 16, 2006 11:20 AM
Please share your comments about the photograph(s) and accompanying write-up. Telling a story about the subject of the photograph(s) is also much appreciated! If you have a gardening question, the best place to ask is on the UBC Botanical Garden Forums. Thank you!
Post a comment
XML Feeds: Atom | RSS 2.0 | RSS 1.0 | What is RSS? | RSS Tools
Botany Photo of the Day and associated images by UBC Botanical Garden staff are licensed under a Creative Commons License. Images and text by non-UBC contributors are copyright the respective photographers / authors (but often have Creative Commons licenses if contributed via Flickr).
About Botany Photo of the Day | Submit Your Photos via Flickr | Submit Your Photos via UBCBG's Discussion Forums
Botany Photo of the Day is a project of the UBC Botanical Garden and Centre for Plant Research, located in Vancouver, British Columbia Canada. UBC BGCPR is a department of the Faculty of Land and Food Systems within The University of British Columbia.
great photo. it says so much about the "vegetation" of the Badlands - an isolated plant in a very harsh setting