Question

Will advanced organisms be the same as complex organisms? Why?

Answer 1

All the life forms like plants, animals or microbes that we see around comprise the biodiversity on earth. These all life forms have a long history of change and the study of history of life forms on earth is called Evolutionary Biology. It is the branch of biology which talks about the word ‘evolution’.

Complete answer:
The advanced organisms are going to be an equivalent as complex organisms. This is because there's an opportunity that complexity in design will increase over evolutionary time. Evolution only results in increases in complexity when complexity is useful to survival and reproduction. The organisms that are formed initially are simpler, while the recently formed or the ones which develop later organisms are more complex.
Evolution means the act of unfolding or unrolling and in simple terms, evolution is an orderly 'change' from one form to another.
The first living organisms originated among organic molecules and an atmosphere that was free of oxygen. They presumably obtained energy by the fermentation of some of these organic molecules. They were anaerobic, capable of respiration in the absence of oxygen. They required ready-made organic material as food and thus they were heterotrophs.
When the supply of existing organic molecules was exhausted, some of the heterotrophs might have evolved into autotrophs. These organisms were capable of manufacturing their own organic molecules by chemosynthesis or photosynthesis.
The organisms performing chemosynthesis are called chemoautotrophs. They were anaerobic. Chemoautotrophs developed the power to synthesize organic molecules from inorganic raw materials. Such a mode of nutrition is even present in some bacteria, e.g., sulphur bacteria, iron bacteria, nitrifying bacteria.
Based on the observation made during sea voyage by Darwin in sail ship H.M.S Beagle round the world. He was appointed as naturalist to study vast flora and fauna of different characteristics. Darwin observed that even different looking and differently behaving organisms share some similarities among themselves. These similarities may either be in the body structure or in the behaviour. He also observed that living organisms share similarities not only among themselves but also with those organisms which became extinct from the earth.
Based on his observations, Darwin concluded that all existing life forms share similarities to varying degrees and also may share common ancestors. More the similarities, the more closely they are related and more closely they are related, more recently they shared common ancestors. Hence, we can conclude that the geological history of earth closely correlates with the biological history of the earth.

Note:
For origin of life, at least three conditions needed to have been fulfilled:
There must have been a supply of self-replicators; Copying of these replicators must have been subject to error via mutation; The system of replicators must have required a perpetual supply of free energy and partial isolation from the general environment.