Plants and animals have to adapt to the long dry periods. Many plants are xerophytic - for example, the acacia tree with its small, waxy leaves and thorns. Plants may also store water, for example the baobab tree or have long roots that reach down to the water table. Animals may migrate great distances in search of food and water. The graph below shows average monthly temperatures and rainfall levels in the savanna region of Mali.
Savannas have warm temperature year round. There are actually two very different seasons in a savanna; a very long dry season winter , and a very wet season summer. In the dry season only an average of about 4 inches of rain falls. Between December and February no rain will fall at all. Oddly enough, it is actually a little cooler during this dry season. In the summer there is lots of rain. In Africa the monsoon rains begin in May. An average of 15 to 25 inches of rain falls during this time.
It gets hot and very humid during the rainy season. Every day the hot, humid air rises off the ground and collides with cooler air above and turns into rain. In the afternoons on the summer savanna the rains pour down for hours. African savannas have large herds of grazing and browsing hoofed animals. Each animal has a specialized eating habit that reduces compitition for food. There are several different types of savannas around the world. The savannas we are most familiar with are the East African savannas covered with acacia trees.
The Serengeti Plains of Tanzania are some of the most well known. Here animals like lions, zebras, elephants, and giraffes and many types of ungulates animals with hooves graze and hunt. Many large grass-eating mammals herbivores can survive here because they can move around and eat the plentiful grasses. There are also lots of carnivores meat eaters who eat them in turn.
Food chains show only one path of food and energy through an ecosystem. In most ecosystems, organisms can get food and energy from more than one source, and may have more than one predator. Healthy, well-balanced ecosystems are made up of multiple, interacting food chains, called food webs. Carnivores lions, hyenas, leopards feed on herbivores impalas, warthogs, cattle that consume producers grasses, plant matter.
Humans are part of the savanna community and often compete with other organisms for food and space. The following list defines and provides examples of the feeding trophic levels that comprise food webs:. National Geographic Society program that supports on-the-ground conservation projects, education, economic incentive efforts, and a global public-awareness campaign to protect big cats and their habitats.
Also called an autotroph. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
Angela M. Cowan, Education Specialist and Curriculum Designer. Elizabeth Wolzak, National Geographic Society. Luke Dollar, Conservation Scientist.
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Text on this page is printable and can be used according to our Terms of Service. Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. A food chain outlines who eats whom. A food web is all of the food chains in an ecosystem. Each organism in an ecosystem occupies a specific trophic level or position in the food chain or web. Producers, who make their own food using photosynthesis or chemosynthesis, make up the bottom of the trophic pyramid.
Primary consumers, mostly herbivores, exist at the next level, and secondary and tertiary consumers, omnivores and carnivores, follow. At the top of the system are the apex predators: animals who have no predators other than humans.
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