Parent material, organic matter, sand, silt, clay, water
For the sahara desert highest has been 136.4 degrees and it can getvery low at night even way under 30 degrees
They group together for warmth when it's cold and they also group together in case of threats.
Scientists combine several well-testedtechniques to find out the ages of fossils. The most important are Relative Dating, in which fossils and layers of rock are placed in order from older to younger, and Radiometric Dating, which allows the actual ages of certain types of rock to be calculated.
