The answer is photosynthesis.
<span>Photosynthesis
occurs in the leaves of green plants. During photosynthesis, carbon
dioxide and water are converted into using the energy of
sunlight to glucose and oxygen. After great evolution of plants, the photosynthetic rate was increased. More plants mean more oxygen produced in the process of photosynthesis. Thus, photosynthesis </span><span> is most responsible for the increase in early Earth’s atmospheric oxygen levels.</span>
Answer:
mutation, recombination, and immigration of genes.
This squirrel lives in a forest and eats only acorns. <span>The squirrel will starve if it can't find enough food. </span>
The hormone described above is the hormone Melatonin.
Melatonin is a hormone secreted by the pineal gland in the brain, which helps regulate other hormones and maintains the body's circadian rhythm. This rhythm is an internal 24 hour clock that plays a critical role when we fall asleep and when awake. When it is dark the body releases more melatonin.