I'd say stone tools. Stone can be chiseled or left alone and be used as a weapon to defend one's self, or as a way of getting food.
Are you asking what animal, cause if so, sea turtle. It's why they bury their eggs
You did not post the scenario
The main portion of the cell is called the soma or cell body. It contains the nucleus, which in turn contains the genetic material in the form of chromosomes. Neurons have a large number of extensions called dendrites.
Algae and Cyanobacteria could mean life is flourishing and is a good food source for some fish in moderation- but if there's a lot of fertilizer runoff, they can grow too quickly and be counterproductive for the environment
