The Emu and Crocodile
Australian Endotherm: THE EMU
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Scientific Name: Dromaius novaehollandiae
Located throughout Australia, not in Tasmania.
Habitat:
Grasslands, open woodlands, savvanah
woodlands.
- Semi- Arid conditions
- Areas that are open with some plant covering.
ADAPTATION 1• Feathers are long, with two
feathers sharing one shaft.
• In cold temperatures:
-Emu will plump its feathers up to
trap a layer of air inside the
thick covering.
- This heat insulates the emu,
keeping the internal
temperature more stable.
• The feathers also have another
adaptation of having black tips.
• The black tips absorb the heat
from the sun.
• The long feather, with the
absorption of sun rays at the
end, occurs far from the skin.
• Tip absorbs it, and stops this
heat from contacting the skin.
• This allows the emu, to stay cool
during the strong heat of the
day.
ADAPTATION 2• The emu pants when the
endotherm needs to cool
down - internal temperature is
too hot.
• Behavioural adaptation.
• Excess heat is lost by
evaporation, moisture takes
heat from body.
• Emu don’t have sweat glands.
• Emu breathes faster, pants and
allows more moisture to be
evaporated from lungs and
mouth, a cooling effect as heat
is expelled.
• Also have nasal passages which
are folded, for breathing in
cooler temperatures - keeps
moisture and heat in the body.
EMU PANTING TO EVAPORATE
MOISTURE AND LOSE HEAT
ADAPTATION 3• The emu adapts to the semi-arid
conditions by using its small
wings to cool down their body
using the small wings which are
not used for flight.
• The wings are flapped and this
cools the animal down by
pushing cool air through the
long feathers to cool the
surface.
• Will receive cool air through
their long feathers as they are
actively walking,and will also
flap their wings which will
provide greater cooling
eventually through to the skin of
the emu.
LOCATION OF SMALL WINGS
Australian Ectotherm: THE CROCODILE
• Scientific Name: Crocodylidae.
• Two Species in Australia:
- Freshwater: Johnstones Crocodile
- Saltwater: Estuarine crocodile
• Found in the warm tropical areas of Northern Australia: Northern
Territory, Queensland and Western Australia.
• Habitat:
-Freshwater: Can live closer inland in: lakes, rivers. Live close to banks
and swampy areas for shelter/hunting etc.
- Saltwater: Usually close to or on coast, and can also live in estuaries,
wetlands, swampy regions and rivers. Lives near swampy
regions/banks for survival.
ADAPTATION 1•
Positions itself on the bank in
a sunny position and sun-bask.
• Will increase the ectotherms
internal temperature as heat
is absorbed.
• Sun baking, on a hot surface
and in a sunny position allows
a large amount of suns rays to
be absorbed as heat energy.
• Quick increase in temperature
so it can continue with
hunting and other processes.
Flattens itself on
the hot surface
ADAPTATION 2•
To withstand the hot temperatures of the
Northern Territory , especially in summer the
crocodile stays in the water throughout the
day to keep as cool as possible.
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Keeps the crocodile from overheating in the
day as water not greatly effected from the
ambient temperatures due to its high heat
capacity.
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The temperature can change in the
environment yet the water the crocodile stays
in will be minimally effected.
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When temperatures drop in the night time,
the crocodile can now comfortably move onto
the bank and hunt for their prey without
becoming overheated.
STAYS IN WATER DURING
HEAT OF DAY
AT NIGHT, WHEN TEMPERATURES
ARE LOWER, GOES HUNTING
ADAPTATION 3• Adaptation of opening its
jaw/mouth greatly.
• When ambient temperature is high
the crocodile will move onto the
bank and will largely open its jaw.
• Cools the crocodile down, as
evaporation of moisture and heat
occurs from the crocodile, due to
the large surface area of the
crocodiles mouth.
• Large surface area allows large
amount of heat can be lost to keep
its head cool.
Bibliography
Books
1) Judith, Brotherton. Mudie, Kate. Heinemann Biology second Edition.
2004: Heinemann
2) Hill, Jennifer. Alford, Diane. Excel: HSC Biology.
2012: Pascal Press.
Internet Sites
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http://www.spiritus-temporis.com/emu/adaptation.html
20/11/2012. Title: Emu.
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http://www.ehow.com/about_6711667_habitat-emus.html
20/11/2012. Title: Habitat of Emus. Elizabeth Jennings.
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http://tolweb.org/treehouses/?treehouse_id=4729
Date Visited: 21/11/2012. Title: The Emu: Dromaius novaehollandiae. Andrew Moon.
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http://www.alicespringsdesertpark.com.au/kids/nature/birds/emu.shtml
Date Visited: 21/11/2012. Title: Nature Notes – Emu.
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http://www.rfadventures.com/emu.htm
Date Visited: 21/11/2012. Title: Emu.
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http://ardeajournal.natuurinfo.nl/ardeapdf/a90-311-323.pdf
Date Visited: 21/11/2012. Title: The adaptive significance of dark plumage for birds in desert
environments. Jennifer, M Ward.
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http://www.torontozoo.com/ExploretheZoo/AnimalDetails.asp?pg=607
Date Visited: 21/11/2012. Title: Emu. Toronto Zoo.
Internet Sites
• http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=1774
Date Visited: 22/11/2012 : Salt-water Crocodile, Estuarine Crocodile. Author: Australian Government
website.
• http://www.aquaticcommunity.com/crocodiles/saltwater.php
Date Visited: 22/11/2012 : Saltwater crocodile.
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http://ozmagic.homestead.com/australiancrocodilefacts.html
Date Visited: 22/11/2012 Australian Saltwater Crocodile Facts.
• http://australianmuseum.net.au/Freshwater-Crocodile
Date Visited: 22/11/2012: Freshwater Crocodile. Author: Chris Hosking.
• http://designeranimals.wikispaces.com/Saltwater+Crocodile
Date Visited: 22/11/2012: Saltwater Crocodile
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http://w3.shorecrest.org/~Lisa_Peck/MarineBio/syllabus/ch9vertebrates/reptilesandbirds/repbird
wp/barbara/adapt.html
Date Visited: 22/11/2012: Adaptations.