Jerry “Sean” Hughes
Lab D
Beetle experiment
Abstract:
Some studies and experiments have shown that population growth can be followed with the flour beetle (Tribolium confusum). Studying these beetles for over a month in varying habitats showed there was a dramatic increase in the populations with larger quantities of food, and a much slower growth rate with more space and the space amount of food. The experiment that I conducted provides a direct correlation between the roles of space and food in a controlled study of these differing populations.
Introduction:
Thomas Malthus, in the year 1798, found that varying populations of both plants and animals are geometrically progressive. Populations increase exponentially, while food supplies increase at approximately the same rate. Because of the progression, any animal or plant could spread over most livable places; however, populations of species remain at a constant level because of death and therefore do not grow indefinitely. Also, there is something in place that restricts population growth (Malthus 1798).
To test Malthus’s statement the Tribolium confusum, or confused flour beetle can be used for certain hypothesis and predictions that test limiting factors, such as food and space.
The Tribolium confusum are functional specimens for a study of these limiting factors because of the growth rate. The growth period of these particular beetles are relatively fast. After approximately 5-12 days of fertilization, the egg hatches into larvae. The larvae last 22-100 days and the pupae last around 8 days (Brereton 1962). These beetles are easy to examine, because they can thrive off of flour with very little moisture, and vermiculite can be used to create space. The life span of the Tribolium confusum tends to last around 200 days; our experiment takes place within that time limit.
Hypothesis:
Hypothesis 1: The amount of food is a limiting resource for the population of the
Cited: Beniot, H.P., Edward McCauley, and John R. Post. 1998. Testing the Demographic Consequences of Cannibalism in Tribolium Confusum. Brereton, J. L. G. 1962. A Laboratory Study of Population Regulation in Tribolium Confusum Brindley, T.A. 1930. The Growth and Development of Ephestia kuebniella and Tribolium confusum Under Controlled Conditions of Temperature Chapman, Royal N. 1918. The Confused Flower Beetle (Tribolium Confusum, Duval) Malthus, T.R. 1798. An Essay on the Principle of Population. Pearl, Raymond. 1925. Biology of Population Growth. NY: Knopf. 260 pp. Young, A. M. 1970. Predation and Abundance in Populations of Flour Beetles