A Study of the Changes in an Aquatic Insect. Population, using Minnows as Predators
- 1Collections of three species of Corixids were made at regular intervals from a small pond at Wilpshire, near Blackburn, Lancashire.
- 2After fifty Minnows had been introduced the proportions of Corixids adapted to the habitat increased.
- 3Various possible explanations are considered, and it seems most probable that the Minnows destroyed those insects which did not harmonize with the background.
- 4There is a lower intensity of selection under natural conditions than that observed in the laboratory.
- 5The influence of selection and isolation in the spread and preservation of various types of characters is also discussed.