COADAPTATION & COEVOLUTION

COADAPTATION & COEVOLUTION

1. CENTRAL TERMS

   • coevolution
   • coadaptation
   • diffuse coevolution
   • evolutionary arm race
   • cophylogeny
   • coevolutionary interaction

2. COEVOLUTION

   • DEF: the change of a biological object triggered by another biological object
   • a process of reciprocal evolutionary change in interacting sp.
     • multiple levels of bio, (DNA - orgnsm)
     • within/btwn sp.
     • not necessarily involve codependence
   • e.g. Ant (Formica fusca) & Lyceanid butterfly caterpillar

3. COEVOLUTIONARY INTERACTIONS

   • Mutualism (+ +) - postive association
     • 1) e.g Mullerian mimicry (Monarch and Viceroy butterfly)
     • 2) e.g. Madagascar orchid and Hawkmoths (plant pollinator)
     • 3) e.g. Ant (Formica fusca) & Acacia (plant pollinator)
       • nibble on the nectar + caterpillar
     • 4) e.g.Ant and Acacia sp.
       • Ant make a nest in the thorn of Acacia, feed on nectaries, give protection from herbivores.
   • Commensalism (+ o)
     • 1) e.g. Anemone (o) Clown fish (+)
       • provide home for the clown fish
     • 2) e.g. Common Wasp, Vespula vulgaris (common model) - Batesian Mimicry
       • A ‘physical ‘ mimic closely resembles an unpalatable or harmful species (the model), and is therefore avoided by predators
   • Antagonism (- +) Predators, parasites or parasitoids share similar signals with a harmless model.)
     • 1) e.g. Sabre - Toothed Blenny (Aggressive Mimicry)
       • pretend to the Labroides Dimidiatus (harmless cleaner fish) - but scarp a chunk of flesh from its site to eat
     • 2) e.g. human head louse (Parasitism)
       • kleptoparasitism (parasitism by theft - seagull, reed warbler & cuckoo)
     • 3) e.g. (in general) Predation
     • 4) herbivory
   • Competition (- -)
     • 1) e.g. food resources
       • Individually sp. thrive
       • together --> competitive exclusion OR niche partitioning
         • competitive exclusion (P. caudatum vs P. aurelia) 1 sp being outcompete by the other sp.
         • niche partitioning (P. caudatum vs P. bursaria) both sp not really well grow (affecting each other) - partitioning the resource

4. CASE STUDIES FOR COEVOLUTION

   • 1) PREDATOR & PREY
     • - predator exerts pressure on prey. - prey exhibiting particular trait ( speed) - predator also exhibiting particular trait (greater speed). - other traits in the sp die out - both sp evolve w a specific trait. - this evo is dictated by the interspecific interaction
     • e.g. lynx and hare
   • 2) PARASITES & HOST
     • e.g. bunny and myxoma virus
       • overtime, the virus less evolve. - bunny develop resistance. - myxoma efficiency dropped
   • ARMS RACE

5. COPHYLOGENY

   • constant trait evolu'on where predator and prey con'nually ‘escalate’ to stay ‘one‐step‐ahead’
   • concordant pattern phylogeny
     • Phylogenies are near mirror images
     • Phylogene'c rela'onships between beetles and food plant nearly iden'cal. i.e. Same or very similar branching pa8ern.
   • Non-concordant
     • not mirror images
     • In this particular example beetles can colonise food plants based on chemical defense profiles. Therefore can jump all around the host plant phylogeny (host shifts)
   • e.g. leaf cutter ant
     • Provides a substrate for fungi on its body
     • The Ants also eat the fungus, transport it to new loca'ons, protects it from parasites and compe'tors
     • Fungi are parasi'sed by Escovopsis parasites.
     • Bacteria cultivated on specialised bodies on the ant to derive antibiotics that curb the parasite activity

6. COEXTINCTION

   • DEF: loss of a species as a consequence of the ex'nc'on of another
   • may involve predator - when a keystone sp goes extinct
     • e.g. Huia extinct due to hunting. Louse became extinct too (stay on the birds skin)
     • e.g. moa & Haast eagle. (moa extinct due to hunting)

7. DIFFUSE COEVOLUTION (AKA GUILD COEVO)

   • Whole groups of species interact with other groups of species leading to evo changes.
   • e.g. Ant (Formica fusca) and Lyceanid bu8erfly caterpillar
   • e.g. Some Pieridae bu8erflies are associated with Cruciferae plants