SPECIES INTERACTIONS EVOLUTIONARY ECOLOGY ECOLOGY OF DOMESTICATION

MutualismCommensalismPredation, etc. CommensalismNeutralismAmensalism Predation Parasitism Herbivory AmensalismCompetition Effect of species 1 on species Effect of species 2 on species 1 Interspecific interactions EXPLOITATION (one species derives a benefit at a cost to another) MUTUALISM (benefiting both species) COMPETITION (cost to both species) Many interactions involve COEVOLUTION

Interspecific interactions Predation – morphological counterstrategies Exploitative -- Predation Predation – physiological counterstrategies Predation – behavioral counterstrategies

Interspecific interactions -- Exploitative Mammal-plant interactions Herbivory – evolution of grazing Plant chemical defenses Mechanical defense of seeds

Mammal-plant interactions Forced dispersal Interspecific interactions -- Exploitative

Parasitism & Disease -- host parasite coevolution Xenopsylla RattusYersinia Interspecific interactions -- Exploitative Borrelia Ixodes PeromyscusOdocoileus Lyssavirus Desmodus Mephitis

Parasite – host cospeciation Geomydoecus Geomys

Interspecific interactions Mutualistic coevolution Ruminant endosymbionts Initially parasities

Often evolve from relationships that were initially exploitative Interspecific interactions Mutualism Mammal – plant mutualism pollination dispersal germination

Mammal-mammal mutualism Interspecific interactions Shared predator vigilance Multi-species herds (ungulates) Mixed colonies (hyraxes) Shared roosts (fruit bats) Badger – coyote hunting “partnerships” mutualism or exploitation?

Interspecific interactions Domestication Food Transport Hunting & Guarding Fiber Disease control??

Canis simensis Africa (Ethiopia) Canis aureus Asia, north Africa Canis latrans North America Canis lupus Northern Hemisphere Canis rufus North America Wild canids Canis “familiaris” Dog – 15,000 ybp ASIA Family Canidae

Tundra British Columbian Mexican Eastern EuropeanIberian Indian Tibetan mt DNA Wolf variability (Canis lupus) Evidence of repeated backcrossing with wild wolves Family Canidae

Dog breeds (relationships inferred from nuclear genes) Basal clade – Central Asia Africa Northern Holarctic Middle East Family Canidae

Family Felidae Felis sylvestris Domestic cat – ca. 10,000 ybp North Africa, Middle East (probably multiple origins) Felis “catus”

Domestic horse --- ca. 6,000 ypb ASIA Domestic ass ca. 6,000 ybp NORTH AFRICA Equus asinus Family Equidae Equus caballus przewalski Paleolithic horse

Genetics 2N = 62 chromosomes 2N = 52 chromosomes 2N = 56 chromosomes 2N = 64 chromosomes Grevy’s zebra (Equus grevyi) 2N = 46 Mountain zebra (Equus zebra) 2N = 34 Plains zebra (Equus burchelli) 2N = 44 Family Equidae

Mule (mare + male ass) Hinny (stallion + female ass) “Zorse” E. caballus x E. burchelli “Zeedonk” E. asinus x E. burchelli Hybridization Equus caballus X Equus asinus Domestic horse/ass hybrids Family Equidae All equid hybrids are sterile due to problems of chromosome pairing during meiosis

Domesticated cattle (Bos) – 9000 ybp Multiple origins (Asia, Europe, North Africa) Probable “hybrid” origin extinct Auroch (Bos primagenius)Wild cattle (Bos taurus) Gaur (Bos gaurus)Yak (Bos grunniens) Family Bovidae

Domestic sheep 6000 ybp Middle East Mouflon (Ovis musimon) Bezoar (Capra aegagrus) Domestic goat 10,000 ybp Middle East Family Bovidae

Reindeer 5000 ybp Northern Mongolia Caribou (Rangifer tarandus) Domestic pig 10,000 ybp Multiple sites (SE Asia, India, Europe, Middle East) Wild boar (Sus scrofa) Family Suidae Family Cervidae

Dromedary ca ybp Arabia Camelus dromedarius Bactrian Camel ca ybp Iran Camelus bactrianus Family Camelidae

Llama 6000 ybp South America Guanaco (Lama guanicoe) Alpaca ybp South America Vicuña (Vicugna vicugna) Family Camelidae The only large mammal domesticates from the Western Hemisphere

Captive (ungulates) Purposefully captured and raised by humans Ecology of Domestication Commensal (dog, cat) Not originally raised by humans but attracted to human modified habitats Six requirements for successful captive domestication (from: Jared Diamond Nature 418: ) 1) Generalist diet 2) Favorable life history (fecundity and growth rate) 3) Docile disposition 4) Captive breeding 5) Social grouping in herds 6) Low panic response Also – genetic “predisposition” for artificial selection (natural variability, hybridization) Types of domesticates

Geography of Domestication Predominance of Eurasia Earliest agricultural economies Large selection of appropriate mammals Why?