Animals gives us nutrients because of the food they eat
Physical weathering because it affects the appearance by breaking down the rock instead of changing its chemical interior
The red blood cells would look just fine or normal in the person who has drowned. Water wouldn't be lost because it wouldn't be attracted to the concentration of the salt water and the salt water would be too large to break the barriers.
Unequal reproductive success - Accumulation of favorable traits over time. Unequal reproductive success. heritable traits best suited to the local environment are more likely to survive and reproduce. Accumulation of favorable traits over time.
