A group of organisms of various kinds living in the same habitat is a(n):

community
ecosystem
food chain
environment

How do you date a sample of rock that you suspect as being one of the earliest on earth

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere,b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify,d)anaerobic bacteria kept thriving with more oxygen

What is the similarities and differences between bacteria and eukaryote?