Download Evolution of Australian Biota Study Day

Evolution of
Australian Biota
Study Day
2013
Taronga Zoomobile session
Student Activities
Yr 11 Evolution of Australian Biota
Workshop
Students notes
Welcome to the Australian Biota Workshop!!
Today’s lesson is jam packed with information about some of
Australia’s most amazing animals. We will cover lots of the
Australian Biota syllabus points plus lots of other information
you will need to have a good understanding of biology.
Some of the main points to have in mind are:
A) Humans only live a short amount of time ‐ lots of the
processes we are studying (ie evolution) take place over
much larger timeframes
B) The world is a changing place ‐ the continents move, the
climate changes, the plants and animals respond to these
changes continuously ‐ its not a one directional change!
C) Fitness ‐ the priorities of an animal are often different to
those of a human. In biology, we consider the ability of an
animal to produce successful offspring as the ultimate
achievement. This is known as fitness.
Basic Vocabulary/Concepts:
1) Nocturnal, Diurnal, Crepuscular
2) Behavioral, Structural and physiological adaptations
3) Ectothermic, endothermic
4) Arid, temperate environments
5) Camouflage 6) Arboreal
7) Vertebrate animals ‐ Fish, Amphibians, Reptiles, Birds and Mammals (Monotremes, Marsupials, Placental)
And lots more…
THESTORYSOFAR...65MYAthe
extinctionofthedinosaursmadewayforthe
‘AgeofMammals’…
Marsupials
Gondwana
55 millionyearsago
Syllabusref.8.5.1,EvidencefortherearrangementofcrustalplatesandǤ
continentaldriftindicatesthatAustraliawasoncepartanancientsuperǤ
continent.Ǥ
Syllabusref.8.5.1—fossilsincommononGondwanan continents,Ǥ
SeparatedContinents
20 millionyearsagotopresent
ImagebyCodyPope(VirginiaOpossum)
MarsupialFossilRecord
SouthAmerica‐ oldest
fossils70mya
Antarctica ‐ someteethand
bonefossilsfound
Australia – oldestfossils
55mya
Monotremes
Evidenceforcontinentaldrift:
MonotremeFossilRecord
ThelocationofknownMonotremefossilsareshown:
LR‐ LightningRidge
R‐ Riversleigh
Steropodon‐ 110myaObdurodon‐ 15‐20mya
Kollikodon‐ 110mya P‐ Patagonia
(verydifferentteethtolaterMonotrematum‐ 65mya
platypus‐typeanimals)(moderntoothtypes)
Illustration– AnneMusser,AustralianMuseum
Placental FossilRecord
FossilsindicatePlacentalmammalswerealsofoundinSouthern
Hemisphere,thoughtheseorganismsdiedoutearlyon.Successful
PlacentalmammalsareevolvinginLaurasiancontinentsatthis
time.
20MYAtopresent
MuskyRatKangaroosevolved20MYAbutstill
liveinremnantareasofrainforestin
NorthernQLD(livingfossil)
KANGAROOEVOLUTION
25MYA.NorthernAustraliaisstillwarm
andwetandcoveredinrainforest.
Kangarooancestorsarearboreal and
havepossumlikefeatures
Syllabus8.5.4—gather,processand
analyseinformationfromsecondary
sourcesanduseavailableevidenceto
proposereasonsfortheevolution,survival
andextinctionofspecies,withreferenceto
specificAustralianspecies
Features:
Features:
20‐15MYASouthernAustraliais
dominatedbysavannah/openwoodland.
Hugeradiationofkangaroospeciesinthis
time.Thefirstmegafaunaappear
Features:
Start:
5‐3MYA
Rainforestsreturntolarge
areasofnorthernAustralia&PNG‐ some
speciesofKangarooreturntoanarboreal
existence—TreeKangaroos
55MillionYearsAgo
Kangaroossplitfromlastcommon
ancestor.Australiaiscoveredin
rainforestandstillconnectedto
Antarctica
Features:
PresentDay
Therearenowover60
speciesofMacropodsin
Australia.RedKangaroos
areoneofthemost
successfulspeciesin
Australia
Features:
Illustrations‐ AustralianGeographic
100000—20000yearsago
Thisisaperiodofrapidtemperaturechange
andthereforerapidplantandanimal
evolution.Evolutionandextinctionsofmany
megafaunaspecies
8MYA
Aridareasincreasing aspolar
icecapsincrease.Hopping
Kangaroospeciesdominatethe
forestfloor
Features:
4‐2MYA
SouthernAustraliaexperienceslarger
aridareasthanpresentdueto
glaciations.Thebeginningofmodern
kangarooevolution.Redsappearat2
mya
Features:
Features:
The Evolution of Kangaroos of Australia
Musky rat kangaroo – a living fossil
Can’t hop
Live in ancient
rainforests
Semi-opposable toe
Semi-prehensile tail
The BIG Evidence
Musky rat kangaroo – a living fossil
Tree Kangaroos
Lumholtz’s
Tree Kangaroo
Bennett’s
Tree Kangaroo
KANGAROOEVOLUTION
RedKangaroosareanextraordinarilysuccessfulspecies.Givesome
reasonsfortheirsuccess,anddescribesomeoftheiradaptations.
Syllabus8.5.4‐ Gather,processandanalyse
informationfromsecondarysourcesanduse
availableevidencetoproposereasonsforthe
evolution,survivalandextinctionofspecies,with
referencetospecificAustralianspecies
RedKangaroosarearelativelynewspecies,buthavehadalongevolutionarypath.
Usingyourknowledgeoftheancestralbodytype,providereasonsforthechangeswecanseeto
theirbodyshapeanddentition.
Itisestimatedthatthereare10‐100millionspeciesoflivingthingsonEarth,butthatbillionsofspecieshave
alreadybecomeextinct.Proposereasonswhysomespeciessurvivelongerthanothers,andwhysomespecies
goextinct.(LiketheearlyplacentalmammalinAustralia!)
Illustrations‐ AustralianGeographic
FERTILISATIONANDSURVIVALOFYOUNGINAUSTRALIANFAUNA
AustralianPythons
Syllabusref.8.5.3.Describesome
mechanismsfoundinAustralianfaunato
ensurefertilisationandsurvivalofthe
embryoandoftheyoungafterbirth
Notes ‐ Reptiles have colonised land successfully by adapting to a dry environment. They have done this by carrying out internal fertilisation, and allowing their young to develop inside a waterproof egg to avoid desiccation or predation.
(Sexual reproduction also produces offspring that are genetically different and possibly better adapted to new and changing environmental conditions than their parents. This gives the species a better chance at surviving in ever‐changing environments).
WhatfeaturesorbehavioursdoPythonshavethathelpensurefertilizationoftheireggs?
WhatfeaturesorbehavioursdoPythonshavethathelpensuretheiryoungsurvive?
ANIMALSEVOLVEINRESPONSETOCHANGINGCLIMATE
Syllabusref.8.5.2.Identifytherelationshipbetweenvariationwithin
aspeciesandthechancesofsurvivalofspecieswhenenvironmental
changeoccurs
Shinglebacklizardsareabletoliveinbothtemperateandaridenvironments.Tobeabletodothistheyhaveadaptations suitedtoboth.
Canyouworkoutwhichfeaturesenablethemtosurviveinatemperateenvironment,andwhichareforsurvivalinanaridregion?
TemperateAdaptations
AridAdaptations
Australiaalreadyhasoneofthehighestextinctionratesoffloraandfaunaintheworld,andGlobalWarmingissettopushevenmore
speciestoextinction.Doyouthinkshinglebacksswillbecomeextinctsoon?Why/whynot?Brieflyexplainwhysomespeciesare more
likelythanothers.tobecomeextinctduetoclimatechange.
ANIMALSEVOLVEINRESPONSETOCHANGINGCLIMATE
Syllabusref.8.5.2.Identifytherelationshipbetweenvariationwithin
aspeciesandthechancesofsurvivalofspecieswhenenvironmental
changeoccurs
Source– M.McKelvey/P.Rismiller
Source– Prof.GordonGrigg
Echidnasshowenormousvariationwithintheirspecies.Asconditionschangeacrosstheirrange,individualsdisplaydifferent variations.
Canyouworkoutwhichoneoftheseismorelikelytobefoundinatemperateenvironment,andwhichonewouldbemorelikelytobe
foundinanaridregion?Whatfeatures/adaptationsindicatedthistoyou?
TemperateAdaptations:
AridAdaptations:
Australiaalreadyhasoneofthehighestextinctionratesoffloraandfaunaintheworld,andGlobalWarmingissettopushevenmore
speciestoextinction.Doyouthinkechidnaswillbecomeextinctsoon?Why/whynot?Brieflyexplainwhysomespeciesaremore likely
thanothers.tobecomeextinctduetoclimatechange.