Because the soil didn't have the same nutrients it has now due to lack of decomposition of other plants and animals.
Biological processes that systematically vary over a 24-hour cycle are called circadian rhythms and are regulated by a cluster of neurons called the suprachiasmatic nucleus.
<h3>What is the circadian rhythm?</h3>
The circadian rhythm refers to the biological process regulated by the duration of a calendar day, which is common for many organisms ranging from animals to plants.
The circadian rhythms enable the maintenance of homeostatic control of physiological functions and thus perform metabolic activities.
In conclusion, biological processes that systematically vary over a 24-hour cycle are called circadian rhythms and are regulated by a cluster of neurons called the suprachiasmatic nucleus.
Learn more about the circadian rhythm here:
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Answer:
They are the first trophic level in an ecosystem and without them the rest of the organisms in the ecosystem would have no source of energy
Explanation:
The autotrophs are the producers in the ecosystem. They manage to produce food for themselves, and they represent the first trophic level, thus they are the basis of any ecosystem. These organisms are the once that produce the energy, and the organisms in the trophic levels above them use their energy to survive. If the autotrophs are removed from and ecosystem, the ecosystem will collapse, as there will be no source of energy for the organisms in the trophic levels above, thus all of them will die out quickly.