Tree of Life Accessibility
It is our goal to make the Tree of Life web site usable to all visitors, including people with disabilities. Most of our accessibility related efforts to date have focused on making the ToL navigation system functional for screen readers and other browsers that are limited in their handling of graphical elements or javascript code. While the standard ToL navigation system makes extensive use of image maps and javascript menus, these display elements are backed by a text-friendly interface, which is complemented by a number of guide pages providing directories of major sections of the ToL web site. We also give users of screen readers the option to directly access the main content of each page by skipping navigation elements at the beginning of the page. If you have difficulty locating information on our site, we recommend the Sitemap for a general overview and the Search page for access to specific content.
Providing easy access for everyone to all materials contained in the ToL database is a work in progress. One area that we still need to address is the use of ALT tags to describe all images and other media displayed on the ToL web site. Since only a few ToL images are currently associated with proper ALT tags, users of non-graphical browsers have access only to image captions, which do not always convey all the information contained in an image. In the future, we will seek funding to create ALT tags for the more than 6000 images that are currently in the ToL database.
In order to improve the accessibility of the ToL for diverse visitors, we are in the process of developing a set of customization tools that will give users control over what kind of information is displayed on a ToL page and how this information is presented. This system will then allow us to provide a series of different versions of the ToL web site with navigation and layout designed to work optimally with specialized browsers that address the needs of users with disabilities. More information about the ToL customization tools is available on the Customizing Your View of the Tree of Life page. At present, we are offering one customization feature that is aimed at improving accessibility to non-graphical browsers: visitors have the option to navigate up and down the branches of the ToL via simple indentend taxon lists rather than image map links. This feature can be implemented by selecting the Show only taxon lists on ToL pages option in the form provided on the Setting Your Preferences page.
We always appreciate getting feedback from our visitors, and our new customization tools now allow us to implement requested changes in the interface that accommodate different user communities. If you have any suggestions as to how we can improve the ToL site, please email them to .