Dampier, Hamelin, and Ningaloo

Rock art, stromatolites, and mass spawning

I. Map boundaries: 20 to 30 degrees South; 108 to 117 degrees East

II. Country (Provinces–Regions): Australia (Western Australia—Gascoyne, Mid West, Pilbara, and Wheat Belt regions).

III. Overview

This map area encompasses deserts and savannas of the Western Australia coastline. The northern and central areas are arid; however, occasional summer tropical storms can cause flooding as happened in December 2010 around Carnarvon. The area around Shark Bay received in excess of nine inches of rain from a tropical storm. In addition, the coastal areas from Shark Bay southward receive winter rains, which support a more savanna-like vegetation and spring wildflower displays. The southern portions of the map area, from Shark Bay southward, are dominated by eucalyptus trees in the flora, while the northern, more desertic areas, are dominated by acacia shrubs. This area was not always a desert. Until three million years ago, northwestern Australia was covered with rainforest. At this time, the Indonesian archipelago rose from the ocean floor, changing ocean currents and blocking warm water traveling south along the Australian coast. This led to the decline of precipitation in Australia, and was the death blow to rainforest vegetation (Perkins 2011).

In the northeast corner of the map, the Dampier Archipelago consists of 42 island nature reserves covered with the spinifex grass characteristic of the Pilbara shrublands. The islands and the nearby Murujuga peninsula are the site of the world’s largest known collection of rock art. Images of birds, marine life, terrestrial life including now-extinct species, and human figures are found, along with stone arrangements. These are believed to be dreaming and ceremonial sites of the Ngarda-Ngarli peoples. Continue reading

Cebadillas, Islands of the Gulf of California, and El Vizcaino

Birthplace of the green revolution; marine mammals in a flooded rift valley in the Sonoran Desert, a deeper canyon than the Grand, and cliff dwellings

I. Map boundaries: 20 to 30 degrees North; 108 to 117 degrees West

II. Country (State): Mexico (Baja California, Baja California Sur, Chihuahua, Sinaloa, Sonora)

III. Overview

In the 1940s, the Rockefeller Foundation was working with Mexico to improve its agriculture. The country was in the middle of a devastating wheat stem rust epidemic. The foundation hired Norman Borlaug as a wheat breeder to try to improve resistance to stem rust. The work was taking place at the cooler highlands near Mexico City. When Borlaug learned that an abandoned experiment station was available in the Yaqui Valley of Sonora, he realized that two generations of wheat could be grown per year. First, the wheat could be planted in the summer in Mexico City. Then that seed could be harvested and grown in the winter in Sonora. By breeding two generations per year, the time it takes to breed new hybrid varieties would be cut in half. The Sonoran experiment station was key to developing the high-yield, disease resistant wheat varieties now in use throughout the world. Today, the Normal E. Borlaug Experiment Station in Sonora is operated by the International Maize and Wheat Improvement Center, and seeds are still being shuttled between Mexico City and the Yaqui Valley (Stokstad 2009). The Yaqui valley marks the transition between the tropical dry forests of Mexico and the Sonoran Desert, which extends north into Arizona. Continue reading


Trapped at the end of the world; an ecological collapse; a microplate with a new family of crustaceans

I. Map Boundaries: 20 to 30 degrees South, 108 to 117 degrees West

II. Country: Chile (Region V—Valparaiso)

III. Overview

More than 2,300 miles from South America and 1,400 miles from the nearest Polynesian island, nine-mile-wide Easter Island, or Rapa Nui, is remote, so remote that only one influx of people is believed to have settled the island about 900 CE. Once settled, the colonists were likely trapped, setting the stage for one of the most famous human-caused ecological collapses.

Easter is home to more than 900, 50-foot-tall, 250-ton statues carved from the volcanic rock found on the island. These were erected between the 10th and 16th centuries and once lined roads leading from the volcanic quarry to other spots on the island. In addition to the statues, the society created ceremonial shrines and the only written language in Oceania. Caves around the coast contain paintings of deities, birds, and fertility symbols. Continue reading

Gan, Pearl, and Xiang Rivers

A land of living fossils; Avatar landscapes in the southeast Chinese Mountains; along the Maritime Silk Road

I. Map boundaries

20 to 30 degrees North; 108 to 117 degrees East

II. Countries

China (Anhui, Chongqing Municipality, Fujian, Guangdong, Guangxi Autonomous Region, Guizhou, Hainan, Hong Kong, Hubei, Hunan, Jiangxi, Taiwan (Pratas)) and Vietnam (Quang Ninh).

III. Overview

The limestone pinnacles amid lush evergreen forests of the Guizhou Plateau and the Nan Ling (South Mountains) are one of the inspirations for the floating mountains in the recent movie Avatar. In 1955, during botanical exploration of Guangxi Autonomous Region, botanists discovered a conifer that had some resemblance to both pines and firs. Further examination indicated that fossil pollen from this new species dates back to the Cretaceous era (greater than 65 million years ago). Today the Cathay silver fir is considered a living fossil and is known from nine locations in the mountains of southern China, five of which are within the map area. The other locations are just to the west. Continue reading

Caicos Turks and Silver Bank

Map of the Month: Caicos, Turks, and Silver Bank
Map boundaries: 20 to 30 degrees North; 63 to 72 degrees West
Countries: Dominican Republic and United Kingdom (Overseas Territory)

The Caicos Bank, which is lined by numerous islands, the Turks Islands, and the three submerged banks located to the southeast (Mourchoir, Silver, and Navidad) are the southeasternmost extension of the Bahama Island chain. Like the rest of the Bahamas, each larger island has a mixture of three vegetation types: pine forests, tropical hardwoods, and mangroves. Smaller islands are viewed as valuable waterfowl refuges, and the large, shallow “banks” are viewed as important coral reef areas. Tourist development has focused on beaches, but there is a flamingo pond on North Caicos, a series of limestone caves and cliffs on Middle Caicos, and expansive salt flats on Turks and Salt Cay. The Dominican Republic has declared Silver and Navidad banks as a sanctuary for marine mammals. Continue reading

Atacama Desert, Southern Puna, and Southern Yungas

Map of the Month: Atacama Desert, Southern Puna, and Southern Yungas
Map boundaries: 20 to 30 South; 63 to 72 degrees West
Countries: Argentina, Bolivia, and Chile

Altitude changes in this area provide a diversity of tropical and temperate habitats, with arid areas the most common. In the north, the Atacama Desert, the world’s driest, is located just east of a Pacific coastal fog desert, which provides some moisture. Further east, elevations increase and the terrain grades into the Puna, a high-elevation desert with volcanoes and saline lakes, including the world’s largest salt flats. On the eastern side of the Andes, there are areas of tropical dry forest and the Yungas, a narrow strip of tropical montane moist forest. At lower elevations east of the Andes the terrain grades into the Chaco, a tropical dry forest of cactuses, bushes, and thorny trees. To the south, the Chaco becomes more arid. The Pampeanas Mountains are a dry-land region of mountains and eroded rock formations in central Argentina. To the west of the arid Chaco, the Argentine Monte is an arid region at the base of the Andes. The southern Andes contain steppe vegetation. The Chilean coastal portions in the south are in the matorral, a Mediterranean scrub vegetation. Continue reading

Balochistan, Lower Indus, and Kathiawar

Map of the Month: Balochistan, Lower Indus River and Kathiawar
Map boundaries: 20 to 30 degrees North; 63 to 72 degrees East
Countries: Afghanistan, India, Iran, Pakistan

One of the cradles of civilization, the area surrounding the lower Indus River includes both temperate and tropical arid areas. The Indus civilization dwarfed Egypt and Mesopotamia in land area, population, and engineering. There were at least six large cities, with trading posts stretching from northern Afghanistan to Oman (Lawler, 2008a). The urban areas collapsed in 1800 BCE (Lawler, 2008b). The boundary between the Indo-Malayan and Palearctic Biomes is just west of the Indus River and shown as a red line on the map. The Kirthar and Brahui mountain ranges define part of this boundary. To the west of the Indus, the largest ecological region includes xeric woodlands covering a series of mountain ranges. However, to the northwest of the Balochistan Mountains, the woodlands grade into deserts extending south from Afghanistan and east from Iran. These deserts contain small areas of irrigated fruit trees and orchards of date palms. There is also a coastal desert and plain region along the Arabian Sea. Along the Indus River and in the Kathiawar Peninsula of India is the tropical thorn scrub region that dominates much of the Indian subcontinent. Tropical fruit and grain crops are grown in Punjab and Sindh using irrigation. Further east along the Pakistan-India border is the Thar Desert and the Rann of Kutch seasonal salt marsh. A small area of dry deciduous forests is found in the Kathiawar peninsula area. Diu is an island at the south part of the Kathiawar Peninsula which is governed as part of the separate state of Daman and Diu. Continue reading