Answer:
if there was no photosynthesis, then we won't have plants. Plants will die out, and we will not get the oxygen needed to survive.
One interpretation of the genetic evidence is that the split of the Neanderthal lineage from the modern human lineage occurred between 440,000 and 270,000 years ago.<span>
It was a long time ago that our ancestors, the Neanderthals, lived on this planet. It was also a long time ago that we started moving away from them and developing in a new manner that would almost completely sever the ties that connected us to them.
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