Answer: when conditions for survival are unfavorable
Since there is two organism involved, sexual reproduction also increase the genetic variability of the population. This makes the population could adapt in wide condition. When the condition of the habitat changes and make survival is harder for general population, there might be someone with genetic variability that become favored instead.
It would be 50 degrees Fahrenheit
Dredging has many very serious implications for reefs, fertilizers that get carried out into the ocean can affect them also.
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Answer:
All of the sinuses as a group are known as paranasal sinuses.