This refers to a biological principle which states that natural selection regulates the number of offspring to which a bird species gives birth to be in line with the number of offspring that the parents of the offspring can successfully nest and protect. A clutch size in excess of the parents’ ability to successfully feed and protect would reduce the number of offspring that can grow into healthy adults. The principle has been applied by other scientists to explain the population dynamics witnessed in other plants and animals. It is named after British ornithologist David Lack.
