How do the human senses assist in communication in the body and between individuals?

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

Number and variety of living organisms includes genetic, species, and ecological types

What is the ecological role of food chains and food webs