Global vs. Local Aesthetics

Global aesthetics:

• in ggplot()
• apply to all layers

ggplot(
  data = penguins,
  mapping = aes(
    x = flipper_length_mm, 
    y = body_mass_g, 
    color = species
  )
) +
  geom_point() +
  geom_smooth(method = "lm")

Local aesthetics:

• in geom_*()
• apply only to that layer.

ggplot(
  data = penguins,
  mapping = aes(
    x = flipper_length_mm, 
    y = body_mass_g
  )
) +
  geom_point(
    aes(color = species)) +
  geom_smooth(method = "lm")