National Geographic : 2009 Apr
world’s major zoos has given me the hands-on opportunity to work with many of the birds known as ratites. Of the larger forms of these, rheas are skittish and relatively harmless, emus are potentially dangerous during the breeding season, ostriches always present a threat, and casso- waries are large, heavy, and possess a mind-set that poses constant danger to handlers. The eyes and attitude in the cassowary head shot are the ﬁnest depiction of an animal’s apparent intent that I can ever remember seeing. Malevolence incarnate. JOHN T. HULLEY Brooklin, Ontario I would like to correct the state- ment that Alfred Russel Wallace was an Englishman. He was born and raised in Llanbadoc, Sir Fynwy, Mid-Wales. As such he would be a Welshman. JONATHAN MORGAN Cardiff, Wales Wallace was born of English parents in the county of Monmouthshire, which is now unquestionably part of Wales, although between 1542 and 1974 its status was ambiguous. Wallace might have been surprised to know that some consider him a Welshman. In his writings he referred to himself as an Englishman a number of times. Reuniting a River Your article on the Klamath was fascinating, but I challenge one aspect. To describe large reservoir hydroelectric facilities as having no carbon emissions is scientiﬁcally unfounded. The World Com- mission of Dams (a nonpartisan panel of scientists, engineers, and policy analysts), in a 2000 report, documented the environmental impact of large dams, including the climate impacts. They found that dams have a wide range of greenhouse gas impacts, from negligible in some locations to very signiﬁcant impacts in others, in some cases nearly as great as fossil fuel power plants. The reasons for this are still under study. MICHAEL HOGAN Programme Director, Power European Climate Foundation The Hague, Netherlands SAVE YOUR SUNDAY FOR FROGS THE THIN GREEN LINE APRIL 5 8PMET/PT pbs.org/nature Funding provided by IT'S NOT EASY BEING GREEN.