Aus flora and fauna

Determinants of climate

• Temperature

• Precipitation

• Ocean and air currents

• Atmospheric chemistry

• Topography

• Latitude

Gondwana separations from Antarctica

NZ 80 mya

Australia 35 mya

S America 30 mya

Ratites

Large flightless brids such as emu, moa, kiwi, cassowary

Root adaptations

Shallow root bed: absorbs nutrients higher due to fast nutrient breakdown

Wide root bed: for stability, given strong winds and shallow roots

Buttress roots: stabilise soil, channel water

Prop roots: support wide-spreading branches

Thorns/spines vs prickles

Have own vascular system vs don’t, usually epidermal cells

Cauliflory

Flowering on the woody stem

Hemiparasitism

Parasitic plant that does photosynthesise on its own

Holaparasitism

Parasite that doesn’t photosynthesise on its own

Mutualism

Symbiotic relationship where both organisms benefit

Commensalism

Symbiotic relationship where one organism benefits and the other is not negatively impacted

Myrmecophyte

Plant mutualist with a colony of ants which hollow it out

Angiosperm

Flowering plant

Gymnosperm

Non-flowering plant

Bryophyte

Moss, liverwort, hornwort

Ferns range

Wet areas, sheltered dry microhabitats

Cycad

Palm-like, produce cones, dioecious, some have root water storage

Cycads range

All tropical/subtropical; fossils show range used to be larger

Cycas genus: no fossil history, likely colonised from Sunda

Dioecious

Separate male and female plants

Monoecious

Separate male and female cones/flowers present on same plant

Australia conifers range

Gondwanan, including S America and some Africa

RED

Carpels (female)

YELLOW

Stamens (male)

GREEN

Petals

PURPLE

Sepals

TOP

Stigma - catches pollen

MIDDLE

Style - connects stigma to ovary

BOTTOM

Ovary - hold ovules (unfertilised seeds)

TOP

Anther - produces pollen

BOTTOM

Filament - holds anther up

Proteaceae examples

Banksia, Hakea, Grevillea, Macadamia

Proteaceae range

Gondwanan distribution in forests, woodlands, heathlands - low nutrient soils

Proteaceae flower structure

Long style presents pollen to pollinators in male phase then receives pollen in female phase

Proteaceae pollinators

Birds, insects, some non-flying mammals

Legume family

Fabaceae

Legume characteristics

Can fix nitrogen, using nodules of root hairs with bacteria

Hard dry fruit with two side seams

2 keel, 2 wing, 1 flag petals

Mostly insect pollinated

Acacia range

Rainforests, wet eucalypt forests, arid, semi-arid

Acacia leaf types

Bipinnate: pinnate with pinnate leaflets

Phyllodes: flattened photosynthetic stems, look like long simple leaves

Elaiosome

Fatty, protein-rich, fleshy structure attached to seeds (esp. in Acacia) which attracts ants, who carry the seeds underground where they are protected

Myrtaceae examples

Eucalypt, tea tree (Leptospermum), bottlebrush, lilly pilly

Myrtaceae secondary metabolite

Oils from oil glands visible in leaves; bitter taste protects against predation, and some can prevent competitor seeds from germinating

Myrtaceae fruit types

Dry, woody, open by splitting at top of ovary; e.g. eucalyptus capsules

Fleshy, berry-like, rarer; e.g. lilly pilly

Eucalypt range

Forest, arid, and alpine, a few rainforest

Australia, NZ, PNG; formerly S America (50+ mya)

Key characteristics to ID/describe eucalypts

Fruit shape, valve and ovary location, pedicellate (individual stem) or sessile (fused directly to group stem)

Bark type

Dorsiventral (different top and bottom) and rounded (juvenile) or isobilateral, longer, and vertical leaves (adult)