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Grizzly bears: As predators, bears keep down the numbers of several species, like moose and elk. They also carry and deposit seeds throughout the ecosystem. Bears that eat salmon will leave their dropping and the partially eaten remains that provide nutrients such as sulfur, nitrogen and carbon to the soil.
<u>Answer</u>: Natural selection.
<u>Explanation</u>:
- The concept of <em>natural selection</em> was given by <em>Charles Darwin.</em>
- According to this concept, in a given environment the organisms that possess <em>better adaptations</em> have<em> higher chances of survival</em> and, leave behind a <em>greater number of progenies</em>.
- When malaria outbreak occurs, the allele frequencies change and only the organisms that possess the alleles which help them to <em>survive</em> this outbreak due to resistance against malarial infection will be selected by nature and<em> hence, this is an example of natural selection.</em>
Sunlight is the main energy source
There would be dead animals overloading the Earth. Think about it, without worms and other things that break down dead things they would still be here and just sit there.
There will be less young organisms and way more older ones - this will put the population into decline