UWC Grade 5 (2009-2010)

The jaguar lives in biodiversity-rich regions of Central and South America. It prefers forest habitats and areas close to water sources (such as wetlands, rivers, lakes etc) as it loves water and is a great swimmer. For example, the Amazon River Basin and the wetland area of Pantanal in Brazil are home to important populations of jaguars (1).

The jaguar is a nocturnal animal – it hunts for prey mostly during the dark hours of the day. (3) Though we have heard of some recent evidence of the jaguar’s daytime hunting as well. (4) The jaguar is a very adaptable animal.

jaguars … hunt by stealth, ambushing their prey from dense cover. Long canine teeth and powerful jaw muscles enable them to kill large animals swiftly, often with a single bite to the nape.

A coin is heavier than a hummingbird!

Madagascar is world-famous for its lemurs—primates that look something like a cat crossed with a squirrel and a dog. These animals are unique to the island and display a range of interesting behaviors from singing like a whale (the indri) to sashaying across the sand like a ballet dancer (the sifaka). Below you will learn more about these fascinating creature

A Food Pyramid in the Hot Desert Biome      Here we see a food pyramid that shows how the Kilocalories pass up the food chain.      The first trophic level is occupied by the primary producers, which are the plants.  Plants make food through photosynthesis. The limiting factor for these plants is the shortage of water, so they produce fewer than 200 Kilocalories of food for the animals for each square meter each year.     The primary consumers, who eat the plants, occupy the second trophic level. These animals have very little to eat, and are small. Many are insects, or reptiles, who are cold blooded and who use less energy to maintain their bodies than mammals and birds do. As food for predators, they provide about 20 Kilocalories per square meter per year for predators.      The predators are the secondary consumers. They occupy the third trophic level. Again we see cold-blooded animals, such as snakes, insect-eating lizards, and tarantualas. Only about 2 Kilocalories per square meter per year are stored in their bodies. In the harsher desert environments, they are the top predators.     In areas where deserts get more rain, more plant material is produced and a few tertiary consumers may be able to survive. They form a fourth trophic level.      This diagram shows the energy available at each trophic level in the hot desert biome. These numbers tell about the numbers of Kilocalories per square meter per year.  Cold Desert Energy Pyramid  Introduction to Desert Biomes  Return to Introduction to Biomes © Elizabeth Anne Viau, 1999. This material may be used freely for instructional purposes but not sold for a price beyond the cost of reproduction. Please inform the author if you use it at eviau@earthlink.net

Mojave National PreserveWorld Deserts World Deserts North American Deserts Protecting Deserts Home Desert lands cover incredible distances. Many who have driven through deserts in the United States may think they are enormous, but they are only the fifth largest in the world covering about 500,000 square miles. By contrast the great Sahara Desert covers almost 3.5 million square miles, the Australian deserts 1.3 million square miles, the Arabian deserts 1 million square miles, while the deserts of Turkestan have 750,000 square miles. Numerous smaller deserts are also scattered across the globe. All are unique, and have adapted to their own particular environments. Global Weather PatternsDeserts tend to occur in two belts that circle the globe. Both the Northern and Southern Hemisphere have this belt located between 15 and 35 degrees latitude, roughly centered over the Tropic of Cancer and the Tropic of Capricorn. This is no accident. The sun is more directly overhead the equatorial region so it receives the most intense sunlight, and this solar energy heats the air. Hot air has two important qualities: it can hold enormous quantities of moisture, and it rises up into the atmosphere. So hot tropical air tends to be moist and rise into the atmosphere. As this air rises it cools, condensing the moisture and converting it to water where it falls as rain. This is why rain forests tend to occur near the equator. What goes up must come down, and gravity pulls this mass of rising air back to the ground. Tropical air typically falls at about 30 degrees latitude on either side of the equator and along the desert belt, but robbed of its moisture it is now hot and dry. The result are often persistent high pressure systems that tend to block incoming storms, or push them into other regions. These patterns make deserts possible, but typically other factor must also intrude to make deserts a reality.

A mosquito has 47 teeth.

A garden caterpillar has 248 muscles in its head.

Indeed, tropical forest is a victim of a spiritual crisis in humanity. The destruction of tropical forest reflects an all too-widespread willingness to submit to an economic determinism every bit as rigid as that of Marx. Egbert Giles Leigh Jr. (1) Rain Forest Destruction, Madagascar Photo: Jonathan TalbotWorld Resources Institute, 2003 We learn from Columbia Encyclopedia that in very early times forests covered virtually the whole land surface of the Earth, apart from the areas of perpetual snow (such as the north pole). (2) And as recently as 19 th century, tropical rain forests in their own right covered around 20% of all the dry land area of the Earth, but this figure was only 7% by the end of the 20 th century. (3) Probably the main fundamental factor that has been invariably pushing rain forest destruction more and more over the decades and indeed centuries, is the demand for the rain forest as a enormous economic and social resource. First of all, tropical rain forests are “treasure troves of nature” – they contain endless supplies of resources widely used in human societies, such as food, timber, raw materials etc. Second, rain forests cover huge swathes of land. And the land has always been a limited resource required for accommodation of ever growing human populations.