what are darwin's 4 observations that drive changes in species over time?

### Variations in traits exist, these variations are heritable, species overproduce, there is competition for resources; not all offering survive

## Step1: Variations in Traits Exist### Darwin observed that individuals within a species exhibit variations in their physical characteristics. These variations can be in size, color, shape, or any other trait.## Step2: Variations are Heritable### The variations that Darwin observed were not just random; they were passed from parent to offspring. This means that offspring often resemble their parents in terms of traits.## Step3: Species Overproduce### Darwin noted that species tend to produce more offspring than can possibly survive. This overproduction leads to a struggle for existence among individuals.## Step4: There is Competition for Resources### Due to the overproduction of offspring, there is competition among individuals for limited resources such as food, water, and shelter. This competition is a key driver of natural selection.## Step5: Not All Offering Survive### Because of the competition and limited resources, not all individuals will survive to reproductive age. Those with traits that give them an advantage in the struggle for existence are more likely to pass on their genes to the next generation.