10 

 Diameter 



Peace on Earth 



STAINED GLASS PLATE 



The delicately-painted dove, carrying an 

 olive branch, soars against the starlit heavens 

 as the luminous earth moves by, and rays of 

 golden light reach out to the universe. American 

 artist, Sharon Crouse, designed the Peace on 

 Earth stained glass Christmas plate in response 

 to the worid's hope for peace. The design won 

 first place in the National Stained Glass Contest. 



The stained glass plate is authorized by the 

 United States Historical Society. 



To create this magnificent work, artists of 

 the Stained Glass Guild make each authentic 

 stained-glass round by carefully painting 

 hand-rolled cathedral glass with 16 colors, one 

 at a time. Then the glass is fired in a red-hot 

 kiln for four hours, fusing paints and glass 

 permanently. They will never fade. 



Artisans place the stained glass into a 

 lead-free pewter rim, decorated with a design 

 of holly leaves and berries. 



The issue will benefit organizations that are 

 aiding victims of wars throughout the world. One 

 Peace on Earth will be presented to the Seaetary 

 General of the United Nations. 



Please send Peace on Earth stained glass 



and pewter plate{s) , aafted by ±e Stained Glass 

 Guild in the U.S.A. at the advance issue price of 

 $125 plus $3 for shipping and handling. Each 

 plate is individually numbered and includes a 

 certificate of authenticity ft'om the society. 

 Limited edition. 



Address 



City State Zip 



D I wish to pay in full at this time. 

 D I wish to pay a deposit of $32 and three 

 monthly payments of $32 each per plate. 

 D Check enclosed for $ . 



(Maie check payable to U.S. Historical Society) 



D Charge: VISA MasterCard 



No. Exp. 



(Virginia residents please add 4.5% sales tax.) 



U.S. Historical Society, Dept. NH6 



First and Main Sts., Richmond, Virginia 23219 



1-800-788-4478 



The United States Historical Society is a non-profit 

 educational organization dedicated to historical 

 research and the sponsorship of projects and 

 issuance of objects which are historically and 

 cotistically significant. 



record include the relatives of such simple 

 modem creatures as sea anemones and jel- 

 lyfish, as well as unusual forms not easily 

 related to living groups. Bilaterally sym- 

 metrical organisms — simple worms — are 

 also represented by thin trails preserved in 

 the sediments. By the beginning of the 

 Cambrian period 545 million years ago, 

 these early faunas had been superseded by 

 diverse associations of complex animals 

 that included the trilobites, mollusks, an- 

 nelid worms, and invertebrate representa- 

 tives of our own phylum, the Chordata. 



Over the past 545 million years, the 

 earth's repertoire of physical habitats has 

 remained relatively constant. Environ- 

 mental diversity, however, has continued 

 to grow, and ever more rapidly. This time, 

 the driving force has been not physical but 

 biological: life itself has become an 

 increasingly dominant aspect of environ- 

 ments. Cyanobacteria, by producing oxy- 

 gen, may have provided new environ- 

 ments for future organisms; in the 

 Phanerozoic, one organism can actually 

 become, or create, the environment for an- 

 other. The colonization of dry land by 

 plants, for example, created a broad range 

 of new habitats, making possible the 



Animals, such as this 565 -million-year- 

 old Inkryloviay7-ow Russia, evolved 

 relatively recently (compared with 

 bacteria, which have a 3. 5 -billion-year- 

 old history). They could not appear until 

 the atmosphere contained enough oxygen 

 to meet their metabolic needs. 



emergence of diverse terrestrial communi- 

 ties {see "One Giant Step for Life," page 

 22). Vegetation provided both food and 

 shelter for arthropods and, later, verte- 

 brates. Novel compounds synthesized by 

 the plants supported new types of bacteria 

 and fungi, including those that digest 

 wood. Many insects evolved in symbiotic 

 partnership with flowers, while mammals 

 and birds developed features that enabled 

 them to harvest fruits and seeds. Jonathan 

 Swift's doggerel proclaiming that "a flea 

 hath smaller fleas that on him prey" is apt, 

 as evolving animals have supplied food 

 and living space for a panoply of other 

 creatures. In our own case, these include 

 the mosquitoes that extract our blood, the 

 tapeworms and bacteria that reside in our 

 intestines, and the protozoans that cause 

 malaria and other scourges of our species. 



In the conventional view, which empha- 

 sizes individual lineages of plants and ani- 

 mals, evolution appears to be a process of 

 replacement. New species evolve in suc- 

 cession, each occupying a particular habi- 

 tat and persisting untfl something comes 

 along that can do the job better or (more 

 commonly) until environmental disrup- 

 tion brings extinction. 



The long view of evolution, however, 

 persuasively argues that biological diver- 

 sity is cumulative. The earth and its biota 

 have evolved in concert, with environ- 

 mental expansion repeatedly engendering 

 biological novelty. New species do not 

 simply replace old ones. Rather, new types 

 of organisms depend directly or indirecfly 

 on those that came before, and even the 

 most intricate ecological edifices of the 

 modem world rest on a microbial founda- 

 tion formed billions of years ago. 



Andrew Knoll 



20 NATtjRAL History 6/94 



