1. P. aurelia upload.wikimedia.org/.../610px-Paramecium.jpg

2. www.ggause.com/gfg05.htm The growth of the "volume" in Paramecium caudatum and Paramecium aurelia cultivated separately and in the mixed population on the buffered medium with the "one- loop" concentration of bacteria. From Gause ('34d).

3. http://www.die- schaedlingsbekaempfer.com/S uchen/Vorratsschadlinge/Reis mehlkafer/Reismehlkafer_Ube rsicht.jpg

4. http://www.amiciinsoliti.it/cibovivo/Resized/tribolium3.jpg

10. Darwin (1859) But how, it may be asked, can any analogous principle apply in nature? I believe it can and does apply most efficiently, from the simple circumstance that the more diversified the descendants from any one species become in structure, constitution, and habits, by so much will they be better enabled to seize on many and widely diversified places in the polity of nature, and so be enabled to increase in numbers. We can clearly see this in the case of animals with simple habits. Take the case of a carnivorous quadruped, of which the number that can be supported in any country has long ago arrived at its full average. If its natural powers of increase be allowed to act, it can succeed in increasing (the country not undergoing any change in its conditions) only by its varying descendants seizing on places at present occupied by other animals: some of them, for instance, being enabled to feed on new kinds of prey, either dead or alive; some inhabiting new stations, climbing trees, frequenting water, and some perhaps becoming less carnivorous. The more diversified in habits and structure the descendants of our carnivorous animal became, the more places they would be enabled to occupy.

11. Lack, 1947

16. Horn and May 1977 “Ranging yet more widely, we note that the larval instars of children’s tricycles and bicycles have typical wheel diameter ratios of 1.3, 1.2, 1.3, 1.2; the adult stages segregate their niches by differences in gear-shift rather than in wheel diameter. “

17. Taper and Case’s criteria for character displacement 1.Sympatric differences > allopatric differences 2.Genetic basis for the differences between pops 3.Trait differences evolved “in place” 4.Variation has function w/ respect to resources 5.Competition for resources related to similarity in trait 6.Differences not due to different resources available to sympatric and allopatric populations.

18. Photo by Dolph Schluter

20. Schluter’s experiment: Is there selection against the more limnetic intermediates in the presence of the limnetic species?

21. Herbivorous Stream Insect and Its Algal Food Trichoptera (Caddisfly) http://www2.waterbugkey.vcsu.edu/php/pics/helicopsyche2.jpg

22. Population Fluctuations

24. Refuges