Ronald observes a sparrow's nest in a shrub outside his home. The table below describes his findings.
Week
Observations
1
Six eggs were laid in the nest.
3
Five eggs hatched, and one egg did not hatch.
One of the chicks disappeared.
7
Three of the chicks learned to fly, and another one disappeared.
What part of natural selection did Ronald observe?
adaptation
overproduction
selection
variation
