Coevolution Types of Interactions A. Overview: B. Competition: C. Predation, Herbivory, and Parasitism: D. Mutualisms Also a feedback loop of selective pressures - coevolution Mutualism

Coevolution Types of Interactions A. Overview: B. Competition: C. Predation, Herbivory, and Parasitism: D. Mutualisms Diffuse: groups of generalists interacting

Coevolution Types of Interactions A. Overview: B. Competition: C. Predation, Herbivory, and Parasitism: D. Mutualisms Specialized/Obligate: single species interacting

Coevolution Types of Interactions A. Overview: B. Competition: C. Predation, Herbivory, and Parasitism: D. Mutualisms Specialized/Obligate: single species interacting Deeper flowers limit access to one pollinator species. This species always gets a reward at this flower; increases its fidelity. Increase in fidelity increases its effectiveness as a pollinator (increases fitness of plant).

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients Rhizobium bacteria fix nitrogen, breaking N2 into N, which reacts with water and oxygen to form NO2 and NO3 that can be absorbed by plant. Infect legumes; plant provides sugars.

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients Ectomycorrhiza and “Endo”- or arbuscular mycorrhizae

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients Lichens – an alga and a fungus

- Types of Mutualisms: Trophic Mutualisms – help one another get nutrients Mixed foraging flocks

- Types of Mutualisms: Defensive Mutualisms – trade protection for food

- Types of Mutualisms: Defensive Mutualisms – trade protection for food Ants ‘farm’ the fungus, culturing it on a chewed-leaf mulch.

- Types of Mutualisms: Defensive Mutualisms – trade protection for food Acacia and Acacia ants

Induced and Constitutive Defenses in Acacia. The species in the right-hand column have mutualistic relationships with ant species - the ants nest in the thorns. Those on the left can attract ants with extra-floral nectary secretions, but the ants do not nest. The Acacia species on the left increase their nectar secretions after damage, inducing wandering ants to come visit and stay a while. The species on the right have to support the ant colonies all the time, and nectar production is uniformly high and unaffected by damage.

Induced and Constitutive Defenses in Acacia. The species in the right-hand column have mutualistic relationships with ant species - the ants nest in the thorns. Those on the left can attract ants with extra-floral nectary secretions, but the ants do not nest. The Acacia species on the left increase their nectar secretions after damage, inducing wandering ants to come visit and stay a while. The species on the right have to support the ant colonies all the time, and nectar production is uniformly high and unaffected by damage. WHICH CAME FIRST??

Induced and Constitutive Defenses in Acacia. Induced defenses first, then the obligate relationship evolved…

Todd M. Palmer, Maureen L. Stanton, Truman P. Young, Jacob R Todd M. Palmer, Maureen L. Stanton, Truman P. Young, Jacob R. Goheen, Robert M. Pringle, Richard Karban. 2008. Breakdown of an Ant-Plant Mutualism Follows the Loss of Large Herbivores from an African Savanna. Science 319:192-195. Fig. 1. Rewards produced in the presence (white bars) and absence (gray bars) of large herbivores by A. drepanolobium occupied by different species of Acacia ants. Ant species' abbreviations are indicated as: Cs, C. sjostedti; Cm, C. mimosae; Cn, C. nigriceps; Tp, T. penzigi. Plants produce fewer rewards when large herbivores are absent and herbivory rates are LOWER. Bribing ants to stay and protect them is less important.

Todd M. Palmer, Maureen L. Stanton, Truman P. Young, Jacob R Todd M. Palmer, Maureen L. Stanton, Truman P. Young, Jacob R. Goheen, Robert M. Pringle, Richard Karban. 2008. Breakdown of an Ant-Plant Mutualism Follows the Loss of Large Herbivores from an African Savanna. Science 319:192-195. Fig. 2. The proportion of host trees occupied by the four Acacia-ant species in the presence of large herbivores (white bars) and in plots from which large herbivores had been excluded (gray bars) for 10 years. And if large herbivores are excluded and plants produce less nectar, then some ants abandon the trees (the mutualist).

“Our results indicate that the large herbivores typical of African savannas have driven the evolution and maintenance of a widespread ant-Acacia mutualism and that their experimentally simulated extinction rapidly tips the scales away from mutualism and toward a suite of antagonistic behaviors by the interacting species. Browsing by large herbivores induces greater production of nectary and domatia rewards by trees, and these rewards in turn influence both the behavior of a specialized, mutualistic ant symbiont and the outcome of competition between this mutualist and a non-obligate host-plant parasite. Where herbivores are present, the carbohydrate subsidy provided by host trees plays a key role in the dominance of the strongly mutualistic C. mimosae, which is consistent with the hypothesis that plant exudates fuel dominance of canopy ant species that are specialized users of these abundant resources (28). In the absence of large herbivores, reduction in host-tree rewards to ant associates results in a breakdown in this mutualism, which has strong negative consequences for Acacia growth and survival. Ongoing anthropogenic loss of large herbivores throughout Africa (29, 30) may therefore have strong and unanticipated consequences for the broader communities in which these herbivores occur.” Todd M. Palmer, Maureen L. Stanton, Truman P. Young, Jacob R. Goheen, Robert M. Pringle, Richard Karban. 2008. Breakdown of an Ant-Plant Mutualism Follows the Loss of Large Herbivores from an African Savanna. Science 319:192-195.

- Types of Mutualisms: Defensive Mutualisms – trade protection for food Ants ‘farm’ aphids and drink their ‘honeydew’

- Types of Mutualisms: Cleaning Mutualisms – trade cleaning for food

- Types of Mutualisms: Dispersing Mutualisms – trade dispersal for food

- Types of Mutualisms: Dispersing Mutualisms – trade dispersal for food

Dispersive Mutualisms – Trade dispersal for food

- Types of Mutualisms: Dispersing Mutualisms – trade dispersal for food Not mutualism (commensal or parasitic)

- Types of Mutualisms: Social Cooperation Nowak, M. A. 2006. Five rules for the evolution of cooperation. Science 314:1560-1563.

- Types of Mutualisms: Fish visit non-cheating cleaners more And watched cleaners cheat less.

http://www.youtube.com/watch?v=frpp6DjCaJU Nowak, M. A. 2006. Five rules for the evolution of cooperation. Science 314:1560-1563.

Coevolution Types of Interactions Evolutionary Effects A. Diversification

Coevolution Types of Interactions Evolutionary Effects A. Diversification Mullerian mimics: mutualists… Radiation of geographic subspecies in one species is largely matched by divergence in other.

Coevolution Types of Interactions Evolutionary Effects B. Speciation and Radiations Leafhoppers, cicadas, and planthoppers and their endosymbionts

Coevolution Types of Interactions Evolutionary Effects B. Speciation and Radiations

Coevolution Types of Interactions Evolutionary Effects B. Speciation and Radiations Radiation of Arthropods stimulated by predation

Coevolution Types of Interactions Evolutionary Effects C. Major Evolutionary Innovations And Mutualisms Endosymbiotic Theory and origins of Eukaryotes

Coevolution Types of Interactions Evolutionary Effects C. Major Evolutionary Innovations And Mutualisms Evolution of multicellularity

Coevolution Types of Interactions Evolutionary Effects The Changing Nature of Interactions A. Competition Facilitation Initially facultative (commensal) relationships, like one plant shading another in the desert) can become competitive when they are large.

Coevolution Types of Interactions Evolutionary Effects The Changing Nature of Interactions A. Competition Facilitation Trees may compete for light aboveground, but share nutrients via mycorrhizal fungi belowground – even between species

Coevolution Types of Interactions Evolutionary Effects The Changing Nature of Interactions A. Competition Facilitation Old dieing trees shunt nutrients to younger trees – even between species- through mycorrhizal networks. May be change in relationships with the fungus, whereby ‘old tree’ is being parasitized while young tree is being facilitated. Net result is shunting of carbon.

B. Mutualism Parasitism Orchids, Euglossine Bees, and Wasps.

B. Mutualism Parasitism