Chapter 10 Species Interactions I: Competition character displacement Fundamental niche vs realized niche K selection vs r selection :

Classification of species interaction Chapter Opener Key concepts page 163 Classification of species interaction 1) Competition 2) Predation 3) Herbivory 4) Parasitism 5) Mutualism Resources competition= scramble or exploitative competition Interference competition=contest comp. Interspecific comp. vs intraspecific comp.

This chapter discuss interspecific competition Resource competition occur a number of organism utilize common resources. Water, light, nutrients, space, plant Mate, water, food  animal

Two species utilize common resources in competition Figure 10-1 Two species utilize common resources in competition Species 1: 16 individuals supported In competition, two species for common resources Species 2: 64 individuals supported

Changes in population size of species 1 when competing with species 2 Figure 10-2 Changes in population size of species 1 when competing with species 2 K=carrying capacity

Changes in population size of species 2 when competing with species 1 Figure 10-3 Changes in population size of species 2 when competing with species 1 Alpha. Beta =conversion factor

4 possible outcomes of competition of two species Figure 10-4 4 possible outcomes of competition of two species

Fish: zooplankton or oxygen Plant: nitrogen or light Figure 10-5 Tilman’s model: Fish: zooplankton or oxygen Plant: nitrogen or light

1.One species win, another extinct 2. Some coexist Figure 10-6 1.One species win, another extinct 2. Some coexist

Competition in Experimental laboratory population Figure 10-7 Competition in Experimental laboratory population Yeast Gause (1932) Moscow Univ. Ethyl alcohol

Figure 10-8

Saccharomyces Saccharomyces Saccharomyces + Schizosaccharomyces Figure 10-9 Saccharomyces Saccharomyces Saccharomyces + Schizosaccharomyces

Schizosaccharomyces Schizosaccharomyces Figure 10-10 Schizosaccharomyces Schizosaccharomyces Schizosaccharomyces +Saccharomyces

Figure 10-11 29.1 oC, 14 % moisture

Figure 10-12 32.3 oC, 14 % moisture

Figure 10-13

Figure 10-14 MacArther (1958)

Figure 10-15 Replacement series

of the competing species Figure 10-16 Replacement series for plant competition: yield decline in the presence of the competing species

Figure 10. 17 Shading by shrub lower ambient temp and improve water availability to animal Plant-plant interaction is not always negative.

MacArthur and Wilson (1967): r selection , K selection Figure 10-17 MacArthur and Wilson (1967): r selection , K selection

Effect size: plant and carnivores –small effect (frog or toads) Figure 10-18 93 species Effect size: plant and carnivores –small effect (frog or toads)

Figure 10-19 >2-300 km <100 km

Grime’s triangle model of plant life history strategies Figure 10-20 Grime’s triangle model of plant life history strategies C, S, R (Disturbance)

Figure 10-22

Figure 10-23 Darwin’s finch Alone

Character Displacement of body size in the Figure 10-24 Character Displacement of body size in the Three carnivorous marsupials in Tasmania

Solid line: direct interaction, dotted line: indirect Figure 10-25 Solid line: direct interaction, dotted line: indirect

Common predator Apparent competition If rabbit abundance increase - Predator increase Eat more pheasants