Answer:
To understand the physical change and chemical change, one needs to know what is physical properties and what is the chemical properties of a substance.
Physical property is characteristic or trait of a substance that can be observed without converting the substance to a new substance. If there is any type of change in these physical properties like changing the appearance or form of matter and does not make a new substance, takes place it is called physical change.
A chemical change is a change in the matter of a substance that creates one or more new substances. This type of change includes the formation, color, of a precipitate, change in texture, and many other changes.
They modify by creating an acceptable environment, and condition for plants
The four principles of natural selection are variation (organisms within a population have their own individual differences in their appearance, such as, markings and color), inheritance (traits passed down to the offspring), high rate of population growth (which leads to their local resources to be more of a challenge to find), and differential survival/ reproduction (organisms in the population with stronger traits are more likely to survive and reproduce, aka survival of the fittest). These four principles work together to respond to chance in the environment by making sure the strongest survive and over time that species will adapt to their environment because the organisms with the better suited traits will pass their traits to its offspring.
I hope that made sense, lol.