Hayley Dent

4th hour

Deserts:
Types:
  • Cold Deserts- Never gets warm enough for plants to grow(besides grasses and mosses), extremely low temperatures.
  • Temperate Deserts(Warm/Dry)- around 1 inch of annual rain fall, and an average annual temperature of 64 degrees.
  • Tropical Deserts(Warm/Dry)-

Climate:
-Extremely low vegetation
-Low annual precipitation that is scattered unevenly
-Evaporation exceeds precipitation
-Gusting winds reaching 75 mph in the winter time

Plant Adaptations:
1.Triangle Leaf Bursage- use long taproots and lateral roots gives the plants a distinctive root zone where other shrubs and plants refuse to grow, cutting down competition for nutrients and water.
2.Saguaro Cactus (the ribs on the cactus expand to take in as much water as possible)Plants have to conserve water.
3.Mesquite and Creosote- Drop their leaves to stay in a dormant state. (reducing water loss in the plant.)
4.Roots adapt to the hot weather.
5. Carry seeds that are inactive until there is enough water for the seed to germinate in the right conditions.

Animal Adaptations:
1.Burrow under ground to stay cool, or in cold deserts, to stay warm. Example, the Gila Monster
2.Flap of skin in nose protect the Camel from sand clogging their nostrils.
3.Camouflage of animals to protect themselves from prey that lurks above. (Desert Toad)
4.Lack of water. Animals must eat the right foods to make up for water loss.
5.Rough food sources- Antelope developed a stomach that helps them digest the only rough hard to swallow foods, making it easier to survive with a larger food selection.

Symbiotic Relationships:

Mutualism:
1. Humming Bird and Ocotillo- Humming bird eats the nectar and the plant is pollinated.
2. Gila Woodpecker and Cactus- Woodpecker eats parasites and insects from the cactus and in exchange the woodpecker gets a home and place to nest.

Commensalism:
1. Brittlebush- A liquid that is secreted from the plant almost daily is used as a glue to Native Americans.
2.Pygmy Owl and Saguaro Cactus- The owl uses the cactus as a home or 'birds nest'.

Parasitism:
1.Fleas and Coyotes- The flea lives int he coyotes fur, living on it's blood and taking its nutrients.
2.Desert Mistletoe and Desert Willow- Mistletoe lives on the Willow extracting its nutrients.

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Lauren Benderoff

Three Types of Deserts:
  • Tropical Deserts-High temperatures; rain fall only 1 to 2 months during the year; few plants, hard surface of rocks; Ex: Southern Sahara
  • Temperate Deserts- Temperatures high in summer and low in winter; more precipitation than tropical forests; sparse vegetation made up of resistant shrubs; Ex: Mojave (Southern California)
  • Cold Deserts- cold winters, warm summers, low precipitation; Ex: Gobi Desert in China

Climate
- Evaporation exceeds precipitation
- Precipitation is scattered unevenly
- Hot and dry winds may occur, producing storms of dust
- Vegetation is low, widely spaced, and sparse

Adaptation themes: Beat the Heat and Every drop of water counts

5 Plant Adaptations

1. Plants must conserve water and lose enough heat so they don’t overheat
Ex: Mesquite and Creosote plants drop leaves to survive in dormant state

2. Succulent plants survive by storing water and synthesizing food in tissue, reducing water loss by opening pores to take up CO2 at night, and having no leaves.
Ex: Cactus

3. Some plants obtain water by using deep roots to tap into ground water.

4. Some plants use wide, shallow roots to collect water after short showers and store in tissue .
Ex: Prickly Pear

5. Some plants have wax-coated leaves to minimize transportation.
Example: Creosote bush



5 Animal Adaptations
1. Some animals have thick outer coverings to minimize water loss through evaporation.
Ex: Spiders and reptiles

2. Many animals store fat during periods of food storages.
Ex: Gila Monster

3. Some animals become dormant during periods of extreme heat or drought

4. Some animal’s wastes are dry feces and a dried concentrate of urine.

5. Many desert animals get their water from dew or from the food they eat.
Ex: Addax


6. Arabian oryxes survive by licking the dew that accumulates at night on rocks or a different Arabian oryxe’s hair.

Symbiotic Relationships
Parasitism
  1. The Wasp and the Praying Mantis- Wasps lay their eggs in the egg case of the praying mantis and feed on the praying mantis’s eggs when they hatch
  2. Fleas and Coyotes- Fleas live on the desert coyote’s body
Commensalism
  1. Cholla Cactus and Cactus Wren- Cholla Cactus hold the nests of the Cactus Wrens. Benefits the Cactus Wren when they build nests there (keeps away from predators), and the Cholla Cactus is unaffected
  2. Creosote Bush and Holly Snub- The creosote Bush benefits by growing under the Holly Snub for shade, and the Holly Snub is unaffected
Mutualism
  1. Ochradenus Baccatus Plant and Desert Mouse- and the plant both benefit. The mouse uses the plant’s berries for food, and the plant grows when the mouse disperses the seeds.
  2. Cacti and Bees- the cacti and the bees both benefit through the pollination process.