Plant-animal relationships
1. Herbivores
Grazers GRASS
Browsers LEAVES
Sap-suckers
Nectar feeders
Stem borers
Chewers
Pollen feeders
Fruit and seed eaters
Gum eaters e.g. marmosets
2. Co-operative relationships between plants and animals
Pollination
Guarding
Protection
Hooks
Birds and fruit
3. Plants that eat animals
Plant defence systems
Physical means of defence
Thorns, spines and prickles
Stings Histamine Acetyl choline
Low growing points
Divarification
Enclosing seeds in a hard coat or prickles
Seed masting E.g. bamboo plants and beech trees
Hiding (stone – cushion plant)
Regeneration Ability to regenerate from the smallest part of the body e.g. smallest part of dandelion rot left in the soil can regenerate into a whole new plant very quickly.
Waxy cuticle and epidermis
Trapping animals Pisonia brunoniana
Chemical defences Chemicals that are produced for no known function in the basis process of life are called secondary compounds Zoopharmacognosy
Chemicals used against pathogens: Antibiotics and phytoalexins Caffeine Chillies “hotness”
Chemicals that deter insects
Canavanine Chewing insects Mimics amino acid arginine
Cyanogenesis Production of cyanide enzyme Glycoside hydrogen cyanide Hydrogen cyanide thiocynate
Pungent and volatile chemicals
Pyrethrins Caterpillars and butterflies have enzyme that detoxifies Chrysanthemum – sesamin
Tannins Produced by oak leaves and camellias Stop insects eating Bitter taste
Alkaloids
Phenols Deter insects Hospital smell = carbolic acid Protect plants from bacteria
Other chemicals Strychnine Morphine Digitoxin Peppermint Cinammon Cloves
Terpens taste peppery like Terpentine Possums are grazing specific, and this had had a dramatic effect near Arthurs Pass. The trees here have been selected and stripped especially rata, kamahi and fuschia trees. Many of these trees are now dead, known as canopy dieback. Possums don’t like terpens, so don’t eat trees such as rimu and horipito