„Cuatro Cienegas Natural Protected Area, Chihuahuan Desert, Mexico.“

INTRODUCTION: IN THE MIDDLE OF THE CHIHUAHUAN DESERT LIES AN UNUSUAL WETLAND C ALLED CUATRO CIENEGAS ("FOUR MARSHES") RECENTLY SET ASIDE BY MEXICO AS A BIOLOG ICAL RESERVE. DERIVING ITS MOISTURE FROM DEEP AQUIFERS, THE LAGUNAS (LAKES) AN D POZAS (POOLS) OF THIS 500-SQUARE-MILE REGION HAVE BEEN ISOLATED FROM ANY OTHER WATER SYSTEM FOR MILLIONS OF YEARS. WATER TEMPERATURES RANGE FROM 68 DEGREES AND COL DER TO BETWEEN 91 AND 93 DEGREES. HERE A RICH POPULATION OF PLANTS AND ANIMALS HAS DEVELOPED, SOME ENDEMIC, SOME UNIQUE TO THE REGION. NATURAL HISTORY PHOTOGRAPH ER GEORGE GRALL HAS ILLUSTRATED THE VARIOUS STRATA THAT COMPRISE THIS ECOSYSTEM . -- LEGEND: A Coahuilan red-eared turtle, Pseudemys taylori, photographed at Laguna del Hundido and endem ic to the region. This is a close-up of its striping pattern . More than sixty species of animals found only at Cuatro Cienegas have been i dentified to date. Copyright: National Geographic / George Grall