pollination ecology - western oregon universitywou.edu/~guralnl/gural/pollination ecology.pdf ·...

Pollination Ecology

• Community Ecology• Pollen• Pollination• Self-pollination • Wind: Anemophily• Animal Pollination

(Zoophily)• Consequences of

Animal Pollination

What is a community?• Community: a group of

populations that coexist in space and time and interact with one another directly or indirectly

• Species interactions: affect one another’s population dynamics

• Natural selection and co-evolution may follow

• Co-evolution – led to ideas of plant

defense – pollination ecology – other plant-animal

interactions: seed dispersal

Pollination Syndromes

• Can be (+,+) interaction

• Plant-animal interaction

• Pollen grains• size tens of microns

Pollination

• Dependence on breeding system

• Self-pollination• Pollen/ovule ratio

Pollination

Delphinium

Grass (Poa pratensis)

• flower morphology• surface

– wind: smooth – animal: sculptured

• Packages (animal only) – dyads and tetrads

(Ericaceae) – Pollina (orchids &

Asclepicadaceae) – viscin threads (Fabaceae

& Onagraceae)

Pollination syndromes

• Self-pollination• Wind• Insect• Birds• Mammals

Prevention of self pollination

Primula spp.: long and short styleForm. Self pollination difficult

Wind: Anemophily• lacks precision

– long range – some weeds 1.25

million pollen grains – Hazel: 600 million – common where

conspecifics close by – vegetation open

seasonally – environmental cues

coordinate flowering

Animal Pollination (Zoophily)

• Insect • Vertebrates • Pollination syndromes

– Flower morphology – odor – color – shape

• nectar reward – sucrose/glucose/fructose concentrations

Insect

Insect

Color cues

Birds

Pollinator rewards

Mammals

Consequences of Animal Pollination

• Distance/Direction • Constancy

• Vector behavior • Handling time • Distance/Direction • Constancy

Distribution of insect species

Gene flow

• genetic consequences – Impact on fertilization – gene flow limited – Raphanus sativus

• Problems – non-pollinating visitors