South University Online
April 16, 2012
“From tiny viruses and bacteria, unrecognized for millennia, to blue whales weighing 200 tons, and fungi that spread for hundreds of hectares underground, the diversity and extent of life on Earth is dazzling. In its life and reproduction, every organism is shaped by, and in turn shapes, its environment. Ecological scientists study organism-environment interactions across ecosystems of all sizes, ranging from microbial communities to the Earth as a whole.” (Malmstrom, 2010)
Organisms occupy just about every environment here on Earth. Every environment offers resources and constraints that mold the appearance of the species that occupy it, and development of long range survival and reproduction of the species. “Some of the broadest patterns of environmental difference arise from the way our planet orbits the Sun and the resulting global distribution of sunlight.” (Chapin 2002) Solar radiation is abundant year round in the tropics. With the warm temperatures the plants photosynthesize endlessly with the nutrients and water available. Solar radiation is limited in Polar Regions. When temperatures are way lower, and the organisms must deal with the lengthy time periods when photosynthesis ends. When temperatures are cold, organisms freeze or slow down. When temperatures climb, organisms loose function or overheat. Many species have evolved some traits that protect against the extravagant temperatures. All living cells require water to function. When it is very cold the water freezes or very hot the water evaporates very quickly, which means that water could be very scarce. Organisms have developed ways to capture and retain water. “In the searing hot Namib desert of South Africa, the Stenocara beetle survives by capturing water from rare wisps of fog that condense in special structures on its back.” (Parker 2008). “All living...