PLANT ADAPTATIONS Steve Blake Aldo Leopold High School Tropical Ecology

RAINFOREST PLANT ADAPTATIONS Limiting FactorsAdaptations SunlightTall trunks, Epiphytes % NutrientsEfficient usage, Effective capture Water in CanopyReduce loss, Effective capture

Strong scent and bright colours of flowers attract insects which assist in pollination Strong scent of fruits attracts animals, which feed on the fruit and assist in dispersal of the seeds Thick, waxy surface of leaves protects against hot sun, heavy rain, and strong winds Aerial roots of epiphytes absorb moisture from the air Tall straight trunks no side branches Thin, smooth bark Buttress roots Shallow spreading root system

A Emergent tree canopy B Large trees of Middle layer C Lower tree layer D Shrub/small tree layer E Ground vegetation

Epiphyte adaptations Advantages of being an Epiphyte in the rainforest: – access to more direct sunlight – a greater number of canopy animal pollinators, – the possibility of dispersing their seeds via wind.

Bromeliads The pineapple family. Thick, waxy leaves form a bowl shape in the center for catching rainwater. Some bromeliads can hold several gallons of water and are miniature ecosystems in themselves providing homes for several creatures including – frogs and their tadpoles – Salamanders – Snails – Beetles – mosquito larvae. Those that die decompose and furnish the plant with nutrients.

One bromeliad was found to contain several small beetles, crane flies, earwigs, a frog, a cockroach, spiders, fly larvae, a millipede, a scorpion, woodlice and an earthworm!

Tree adaptations Height –50-85 m – Light competition Biologically diverse ( species/hectare) – Reduce disease transmission Smooth bark – Reduce epiphytic growth

Some rainforest trees have smooth, thin exfoliating bark By frequently exfoliating patches of thin, papery bark, the tree can shed epiphytes Here an liana is about to lose its grip on the tree trunk

Tree adaptations (continued) Leaf shape to shed water – discourage epiphytes, send water to roots Leaf stalks rotate to follow sunlight

Buttress Roots – Compensate for shallow roots Because nutrients are shallow – Support – grow out from the base of the trunk up to 15 ft above the ground. Extended roots increase area over which nutrients can be absorbed.

Prop or Stilt Roots Stabilize trees in flood areas like mangrove trees

Mangrove with prop roots

Stilt roots of “Walking palm tree” move toward light by adding prop roots to light side and losing them on dark side.

Matapalos (Strangler Fig) Hemiepiphytes: – Start as epiphytes and grow very slowly to ground—then accelerate growth rapidly. Why? – Eventually kill and replace tree and becomes hollow inside—home to animals that deposit nutrients.

David Attenborough video of Strangler Fig!!

An adaptation rare in the Neotropics… Carnivorous plants! – Trap and consume animals for their nutrients

Pitcher plant - a carnivorous plant. slippery rim tendril Insects falling into the pitcher are digested, and nutrients which are released are absorbed by the plant.

Drosera capillaris, (pink sundew) At the end of each tentacle is a gland that secretes droplets of sticky fluid. Insects attracted to odor become stuck. Tentacles slowly enclose the victim and secretes digestive enzymes and acids that dissolve the body. Utricularia, bladderworts Utricularia foliosa Utricularia gibba

Drosera capillaris (sundew)

Utricularia gibba: trap showing trigger hairs Utricularia foliosa

Lianas and vines Thick, woody stems up to 3,000 ft long Begin life on forest floor but use trees for support to climb upwards towards sunlight 90% of species in rain forests.

Lianas (continued) Attach to trees with sucker roots or tendrils and grow with the sapling, or climb by winding themselves around the trunk. When they reach top of canopy they spread to other trees or wrap themselves around other lianas. Gives support against winds to the shallow- rooted, top-heavy trees. However, when one tree falls several others may be pulled down.

Seed Dispersal Seed dispersal processes dominated by vertebrate dispersers – involve individuals belonging to hundreds of species

Dispersal Types Gravity (‘Gravichory’) Wind (Anemochory) Water (Hydrochory) Ballistic (Autochory) Animal (Zoochory) – Epizoochory (transported externally) – Inadvertent (cached) – Myrmechory (ant-dispersed) – Endozoochory (through the digestive tract) images:

Fruits Nutritive fleshy pericarp or pulp; Chemical attractant; Colors Fruit size varies from 0.01g to 40g In Neotropical forests, % of the canopy trees bear fruits adapted for animal dispersal, while close to 100 % of the shrubs and sub- canopy trees produce fleshy fruits

Frugivores High variety of tropical bird, bat, ant, mammal dispersers Frugivore size ranges from ~10g tyrannid flycatchers to African Elephant Enormous differences in fruit and frugivore scales imply an enormous potential range of phenomena

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