Answer:
It has physically increased in size. Often, growth of a multicellular organism occurs as more cells are created. In unicellular organisms (like bacteria), growth still occurs. ... For this reason, most biologists will tell you that development only occurs in multicellular organisms, not in unicellular ones.
Answer:
Until recent history,extinctions have always happened gradually and on a small scale.
Explanation:
Extinction occur when environmental factors like natural disaster,habitat fragmentation,over exploitation,global change don't favor the survival of species thus gradually leads to extinction of species.
Some times human activity becomes the major problem for extinction.More over,poor reproduction,decline in population number and genetic inbreeding also leads to extinction.
99% of all species that exist on earth become disappeared.
Evolution leas to speciation which leas to formation of new species but species become extinct when they are unable to survive against competition.
What ecosystem are you talking about ?
