Wildlife of Gondwana

Transcription

Wildlife of Gondwana
Unit of Work: Level 4
PrimeSCI!
Credits
This teacher resource booklet was devised and produced by the following
members of the staff at the Monash Science Centre (1990 - 2012):
Professor Pat Vickers-Rich
Priscilla Gaff
Dr. Corrie Williams
Special thanks to: Kathy Smith, Dr. Sanja Van Huet
and Cindy Hann - for the education framework and content
Special thanks to: Peter Trusler - for the artwork
The cliparts used in this kit are from CorelDraw 7.
No part of this document may be copied or distributed without the written permission of PrimeSCI!
This excludes the use of handouts for classroom activities in conjunction with this kit.
Contact Us
PrimeSCI!
9 Rainforest Walk
Monash University
Clayton, 3800
Victoria
Australia
The Education Team at the
Monash Science Centre was
proudly supported:
The research on the fossils from
the Precambrian included in the
exhibition has
been generously
supported by:
Phone: 613 9905 1370
Fax:
613 9905 1312
primesci.monash.edu
IGCP493
Special Thanks
The Monash Science Centre would like to
thank Visions of Australia - an Australian
Government Initiative, for their generous
support for the 'Wildlife of Gondwana
Exhibition'.
The Monash Science Centre would also
like to thank the School of Geosciences,
Faculty of Science, Monash University, for
their support of the scientific research and
research materials that are on display in
the 'Wildlife of Gondwana Exhibition'.
Education Level of this Kit
This education kit is suitable for the following year levels:
Prep
1
2
3
4
5
7
6
2
8
9
10
11
12
WILDLIFE OF GONDWANA EXHIBITION
Level 4 Education Booklet
PrimeSCI! © 2015
Index
Item
Page
Credits
How to Contact Us
Index
Key Understandings
National Statement in Science
Part 1: What do we know?
Part 2: What do we want to find out?
Part 3: How can we find out more information?
Part 4: Processing the experience
Activities 1 - 7
Part 5: Linking activities
Background Information
Glossary
Resources
2
2
3
3
3
4
7
9
9
10-19
20
21-22
23-24
25
Grades 5 & 6: Key Understandings
Key Understandings:
4A fossil is the preserved remains of once-living organisms
4Fossils can be formed in a variety of ways.
4Fossils may provide information about the changes that have occurred on Earth over
time.
4Scientists use geological time periods to distinguish specific periods of time in Earth's
history.
4Scientists use fossils to reconstruct living organisms.
4By studying these fossils, palaeontologists can begin to suggest what kind of food they
ate, their behaviour, the conditions they lived in at the time, etc.
4Living things have changed over time.
4Environmental factors such as changes in climate caused by meteorite or volcanic
activity could have lead to the extinction of dinosaurs.
National Statement in Science:
LEVEL 4: Life & Living - Biodiversity change & Continuity
4.7 Identifies events that affect the balance in an ecosystem.
4.9 Explains how living things have changed over geological time, using evidence from
various sources.
3
PrimeSCI! © 2015
PART 1: What do we know?
1. Locating the Boundaries of Experience.
The experiences outlined in this document invite
students to think about ideas and information related
to the topic area. In many cases simple stimuli, both
visual and auditory such as picture charts, multi media
images from internet sites, pictures from books, texts,
story telling, etc., have been selected to provide a way
to promote discussion and prompt children to recall
any existing relevant knowledge they may have to
contribute to the exploration of the topic in the
classroom.
Creating a Thinking Board
TEACHER BACKGROUND:
4Act as scribe for your class and create a “Thinking
Board”.
4To find out what the students prior knowledge is on
the topic of fossils, ask the students "What do you
know about fossils?"
4Use the board to record the students ideas and
information.
4This is also the place to record any questions that
have been raised during, or as a result of sharing
ideas.
4Alternatively, students ideas can be written in
outlines of dinosaur shapes on the board.
4In this activity, all student ideas and contributions
are valued and important.
4This board represents the students' areas of interest
in relation to this topic and is therefore useful as a
'working display' in the classroom.
4The board can be returned to on a regular basis. It
may be used many times; as a starting point for
research work, to inform the selection of activities
used in the classroom, to revise topic language, to
display new pieces of information as appropriate
and relevant, to contribute information when
constructing a glossary of terms, etc.
4This input forms the basis for future direction and
topic exploration within the unit.
4
some
dinosaurs
were very large
birds
can be
fossils
fish
can
be
fos
sils
PrimeSCI! © 2015
Follow Up: Student Journals
Throughout the topic students write entries on a regular basis
in their journals. The focus of these entries is to enable the
student to record a new piece of information or an
observation they made that was of particular interest to them.
These entries may be shared. At the completion of the first
session related to the Thinking Board students are
encouraged to record such an entry in their journal.
Encourage the use of drawings and key words. Journals may
be an effective strategy for encouraging students to reflect on
new information and consider how this may link with their
existing ideas. These entries are also a useful tool when
assessing student involvement and interest in the unit topic
and may determine the future direction of unit planning.
Post Box Activity
Equipment:
"
"
"
4 boxes to be used as postboxes.
Each box is labelled with a number between 1-4.
Student activity sheets Post Box Activity (see blackline masters).
This activity is designed to provide students with the opportunity to express their understanding of
several questions related to the topic. The activity is completed anonymously, however, all answers
must be a sensible response. This activity also exposes students to a range of views held within the
class and provides an opportunity for students to consider views that are perhaps alternative
explanations to their own. It is also very informative for the teacher to identify the range of views that
exist within the class and the prevalence of these views. These findings can then be used to inform
further teaching in this topic.
i KEY REFERENCE: For further information on this teaching strategy refer to:
Baird, J. Northfield, J. (Eds).(1995). Learning from the PEEL Experience. Monash University Printing Services.
Procedure:
«Distribute to students the blackline master sheet headed POSTBOX ACTIVITY.
«Read through the questions that are listed on the sheet.
«Explain the sequence of procedure to be followed.
«Students work individually and complete their responses to the questions.
«Students post their responses into corresponding boxes.
«Students are placed into four groups. Each group receives one postbox, then the students read
through the responses and categorize these to represent the range of views held.
«Each group presents a report to the class group outlining the types of responses present in their
box and the prevalence of these views.
5
PrimeSCI! © 2015
Post Box Activity
1
What are fossils?
2
What can fossils tell us?
3
How do fossils form?
4
What kinds of things can be fossilised?
6
PrimeSCI! © 2015
PART 2: What do we want to find out?
There is research evidence (Biddulph 1990, p.68) that when children have
that opportunity in science they prefer learning from their own questions
and value learning about other children's questions as this often
challenges them to think about aspects of a topic they had not considered.
Fleer, M. Hardy, T. 1996
Pinning Questions on the Wall
4Return to the Thinking Board constructed in the last session.
Review the information.
4Working with students, discuss the information on the board.
4Encourage students to write one or two questions they hope will
be answered during the unit.
4These questions are written in large print and pinned on the walls
of the classroom.
4They are removed only when the author of the question feels it
has been answered, such as after their visit to the exhibition. In
fact, students could bring their question along to the exhibition,
and write the answer on the back.
This activity has the possibility to set an agenda for the unit, to
involve the students in the structure and focus of the unit, to identify
any gaps in information to be taught, to focus on a particular task
each lesson and to reflect on what has been achieved and learned
throughout the unit of work.
How d
o scie
ntists
what
know
dinosa
urs at
e?
What is a fossil?
did life
where
d
n
a
n
e
Wh
?
h begin
on Eart
(Reference: Learning from the PEEL experience Page 242)
Follow Up: Student Journals
At the completion of the 'Post Box Activity' and the
'Pinning Questions on the Wall,' students are encouraged
to record an entry in their journal describing any knew
information they now know about fossils. Encourage the
use of drawings and key words. Journals can be an
effective strategy to encourage students to reflect on new
information and consider how this may link with their
existing ideas. This entry will be a useful strategy when
discussing the coming exhibition with students.
7
PrimeSCI! © 2015
Preparing for the Visit - Topic Vocabulary
Fossil Pictionary
Using the topic vocabulary - students could play 'Fossil Pictionary'.
This activity allows the students to practice using and becoming
familiar with the topic vocabulary.
Procedure:
4Students work in teams of 5.
4There are 2 teams and 1 person who acts as the judge.
4One student in the team of two is the 'drawer', the other is the 'guesser'.
4The 'judge' shows the 'drawers' the word card, for example 'bone'.
4The 'drawers' have to draw the word, and the 'guesser' has to guess the word.
4Keep playing until all of the word cards have been used.
claw
aquatic
palaeontologist
tooth
terrestrial
rock
jaw
skull
skeleton
femur
(thigh bone)
megafauna
vertebrate
dinosaur
reptile
invertebrate
fossil
carnivore
exoskeleton
extinct
herbivore
Gondwana
trilobite
mammal
glacier
8
PrimeSCI! © 2015
PART 3: How Can We Find Out More Information?
Visiting the Exhibition and the students complete Scavenger Hunt Sheet.
PART 4: Processing the Experience.
TEACHER BACKGROUND:
Exploring individual children's understanding of and opinions about science is an important
component of science teaching as these ideas have direct implications for their learning and
the teaching of science. Providing a range of ways for students to express their
understandings is also crucial. Exposing students to a variety of alternative ideas and
interpretations encourages them to consider alternative viewpoints to their own. This can
enhance learning. It can also expose the students to how science really works: hypothesis,
testing, and refinement or even rejection of ideas.
The activities below are designed to encourage students to process and make sense of
information they have covered in classroom research and through their visit to the exhibition.
The following activities focus on visual representation of information, providing students with
a vehicle for expressing their understandings and conveying these to others.
Plus, Minus, and Interesting
After your visit to the exhibition, ask the students to rule up a
table like in the picture. Under the heading 'Plus', students
should write about what they liked in the exhibition. Under the
heading 'Minus', students should write about what they didn't
like about the exhibition. Under the heading 'Interesting',
students should write about what they found interesting. This
can then be used as a point to have a class discussion about
the exhibition.
Plus
Minus
Interesting
Fossil Diorama
Have students select a fossil of their choice. Students share with
the class their choice and their knowledge of this animal or plant.
Working independently, in pairs or small groups, students now
construct a diorama in a shoe-box depicting an interesting scene
of this fossil's existence. Students may need to undertake further
reading and research to find out more about the fossil they have
selected to determine what other animals and plants are suitable
for inclusion in their diorama.
Dinosaur Vote
Create a class room graph where each student votes for their
favourite dinosaur. Each student must write their name on a
piece of paper (all pieces of paper need to be the same size)
with the name of their dinosaur, these pieces of paper can be
used to create a bar graph in the classroom.
9
PrimeSCI! © 2015
Activity 1: The Fossil Story
This activity encourages students to think about how a fossil might form, by reading
through the jumbled story and placing the pieces back together.
Equipment:
&Activity sheet 'The fossil Story' - one per group
&Scissors
&Glue (don't give out the glue until after the students have discussed the order of their
story).
Procedure:
4Distribute one copy of the Fossil Story to each student.
4Put students into groups of three.
4Students read through the sections to tell the story of how a fossil was formed.
Students must reread to check that the sequence makes sense.
4After the students have sorted their pieces, invite students to share their stories.
4Are all sequences the same? Do some students have different sequences of events
and do these make sense? Discuss.
Leaellynasaura running away from a predator.
Image reproduced with permission of Australia
Post. ©Australia Post 1993. Artist: Peter Trusler.
10
PrimeSCI! © 2015
Worksheet: The Fossil Story
Long ago a small dinosaur reached a muddy riverbed. It was looking for food.
It stood on its hind-legs and was no taller that 1 metre; it was a plant-eating
dinosaur called Leaellynasaura.
The rock was covered by layers of sand and Earth. Over time, these layers
compressed into rock, and inside was the fossil of Leaellynasaura.
Weeks passed and the mud and sit around the carcass dried and the wet
ground hardened. The muscles and flesh of the dead dinosaur rotted away
leaving only the skeleton.
Leaellynasaura drowned in a flood. The flood waters receded and the river
became dry again. The body of the dead dinosaur now lay on the river
sandbank.
Over time pieces of the skeleton were moved by other animals and some
bones were washed away in more floods. The bones settled in many placed
and were covered by mud, sand and silt. The sediments hardened and
dried. Eventually it became rock. The bones trapped in the sediments
became rock too.
Conditions were cold and extremely wet. The river was beginning to rise.
The river water flooded the area, and Leaellynasaura was caught in the rising
waters and struggled to survive.
11
PrimeSCI! © 2015
Activity 2: Make a Fossil in 'Amber'
So far we have been looking at fossils that form in sedimentary rock. However, fossil
can also form in organic matter - such as amber.Amber is fossilized tree resin. Trees today
secret resin, which can form amber. Some amber can be as old as 300 million years old.
When the liquid resin is secreted by the tree and flows down its trunk, it traps creatures
and objects. Once the animals are trapped, and the resin goes hard, the animal can be
persevered inside the amber for millions of years. Pieces of amber can contains a fairly
complete fossil insects, lizards and even frogs!
In the movie "Jurassic Park," the scientists extracted DNA from mosquitos trapped in
amber. However, this is not possible for dinosaurs, as the DNA is so old, that it has since
broken down far too much for scientists to be able to 'recreate' the animal. However,
fossils in amber are a very important part of our fossil record as the organisms trapped
inside are so beautifully preserved. To have a look at some fossils in amber, go to this
website: http://www.amnh.org/exhibitions/amber/
Objective:
To develop an understanding of how fossil can be formed in amber.
Equipment:
* Gelatine
* plastic teaspoon
* small plastic cups
* Food dye
* warm water
* insects, spiders, leaves
'amber fossil' made in gelatine
Procedure:
! Collect insects and leaves to go into your amber. You may need to use a net to capture
some. Alternatively, you could leave out a cup of sugary water outside, as insects will
come and drink and then fall in. Be careful pulling the insects out - as there may be
bees and wasps, and even though the animal is no longer alive, the sting may still be
able to sting you!
! To make the amber, first put 2 teaspoons of gelatine powder into a small plastic cup.
! In another cup, add 2 drops of yellow food dye, and 1 drop of red food dye. Then add
about 2 tablespoons of warm water.
! Pour a half of your water mixture on to your gelatine. Stir. Add more water if you think
your mixture needs to be more runny.
! Next, put your insects and leaves into the liquid.
! Leave your 'amber' to set for at least 30minutes.
! After your 'amber' has set, using a plastic knife, carefully take your amber out of the
cup.
Questions:
How did the insects become trapped in the gelatine?
Why did we used gelatine, not really amber?
How is the experiment like the real thing? How is it different to an insect being trapped in
amber?
Why do you think palaeontologists might like studying fossils preserved in amber?
12
PrimeSCI! © 2015
Activity 3: Toilet Paper Geologic Time Scale
Objective:
A visual demonstration of the enormous extent of geologic time compared to recent time.
Equipment:
þ
One roll of toilet paper, 231 sheets or more
þ
Felt-tip marker, several colors.
þ
Sticky-tape for repairs
Procedure:
4Prior to starting the toilet paper roll out, have each student fill in the activity sheet. This
should help you identify students' prior knowledge. Students can revisit the sheet after the
game, and assess their understandings and add any new knowledge.
4After this, starting at one end of a long hallway or outside in the courtyard
4Unroll the toilet paper, and mark the important events on the toilet paper as you roll out
the paper (or you may like to prepare the events on the paper ahead of time).
4You may need to make 'repairs' of your geological time scale with the sticky-tape.
4One sheet of toilet paper = 20 million years.
SPACING
sheets Event
0.00
0.001
0.09
0.15
0.50
2.50
3.00
3.25
7.50
10.5
11.00
11.00
16.25
20.00
20.00
21.50
24.50
27.50
30
70
170
220
230
Geological time
(years before present)
0
195,000
1,800,000
3,000,000
10,000,000
50,000,000
60,000,000
65,000,000
150,000,000
210,000,000
220,000,000
220,000,000
325,000,000
400,000,000
400,000,000
430,000,000
490,000,000
550,000,000
600,000,000
1,400,000,000
3,400,000,000
4,400,000,000
4,600,000,000
Present
Modern man (Homo sapiens)
Homo erectus
Australopithecus africanus
Beginning of Antarctic ice caps
Separation of Australia and Antarctica
Early primates
Most Dinosaurs became extinct
Early flowering plants
Oldest Turtle
Oldest mammals
First dinosaurs on Earth
First reptiles
Early trees, formation of coal deposits
Oldest insect
Early land plants
Early fish
Early shelled organisms
Breakup of early supercontinent
Early multicellular organisms
Early bacteria & algae
Oldest known rocks on Earth
Origin of Earth
=20 million years
13
PrimeSCI! © 2015
Toilet Paper Geologic Time Scale
Fill this column
in first.
Fill this column
in AFTER the game.
Write your first answer
before you play the Toilet
Paper Game.
Are your answer still the
same, or do you have a
new answer?
How old is
the Earth?
How long
have humans
lived on the
Earth?
When did
dinosaurs
become extinct?
Did dinosaurs live
on the Earth at the
same time as
humans?
Which animals
have been living
on Earth the
longest,
dinosaurs or fish?
14
PrimeSCI! © 2015
Activity 4: Creatures with No Eyes!
Ediacarans (organisms which lived about 548-575 million years ago) lived in the dark
because they had no eyes! We rely on sight to identify objects, to find out way, to appreciate
changes in our environment and just to get through our life each day. Imagine - what it would
be like to live in a world where you could not see?
Procedure:
4Put students in groups of 4.
4Give each group a picture of one of the Ediacaran animals (pictured below).
4Each group, or student, first needs to make a model of their animal in play-dough or
plasticine.
4Check their animals with the picture - make sure they didn’t add any eyes to the animals.
4Next, each group needs to brainstorm about how they think each animal survived in its
environment if they couldn’t see.
They might like to brainstorm the following questions:
Is it possible, and how would it:
ð find food?
ð tell when it found another one of its own kind if it couldn’t see the other animals?
ð tell if it is night or day? And would it matter?
ð tell if it is winter or summer?
ð tell if other animals are nearby?
Remind the students that these animals couldn’t talk like you and I - they had no voice box!
All of these creatures lived in
oceans that covered Australia,
parts of Namibia, northern Russia,
545-575 million years ago!
Dickinsonia
This animal lived about 550
to 565 million years ago. It
looked like a kind of worm
but it may have been
something completely
different! It moved slowly
along the ocean floor, eating
the slimy microbial (like
algae) mats.
Charniodiscus
This animal lived 540 to
553 million years ago. It
most likely lived like a
modern 'Sea Pen',
attached to the ocean
floor and filter feeding or
absorbing food from the
water.
15
Pteridinium
This animal lived in the
oceans about 565 to 545
million years ago. It may have
lived partly buried in the
ocean floor sediments.
Palaeontologists still need to
keep studying this creature to
really understand it!
PrimeSCI! © 2015
Activity 5: Dinosaur Footprints
Some dinosaurs were really big. Others were not so large, but many left footprints in sands
and clay when they walked. Some of these were fossilised and have been found by
palaeontologists, both amateur and professional.
On the back of this page are several drawings of a real Australian dinosaur trackway, found
near Winton in southwestern Queensland, Australia.
Interpreting the Fossil Footprints
Photocopy the track-way for each student.
Let the students know that they are now 'palaeontologists', as they will be studying fossil
footprints, much like a palaeontologist would who studies 'trace fossils' - otherwise know as
'ichnofossils'.
Discuss the following questions with the class:
1. How many animals made the trackway?
2. What kinds of animals do you think they were? Why do
you think this? Give evidence.
3. How many toes did each animal have? How can you
tell?
4. In what direction did the animals move?
5. Did they change speed or direction? How can you tell?
6. What do you think might have happened to produce
this trackway?
Students could either:
$ write their own story
$ work together and roll play their story
$ draw a cartoon of the story
Remind students that they can interpret the track-way
however they like, so long as they can justify their story
using the evidence. Alternative stories might be: the
animal leaving behind the small footprints was a bird and
it flew away, or a baby dinosaur and it got on its mother's
back, or maybe one of the dinosaurs was eaten!
16
PrimeSCI! © 2015
Activity 5: Dinosaur Footprints
17
PrimeSCI! © 2015
Activity 6: Interpreting the fossil record
Paleontologists don't get to see the animals they study in action! They don't get to
observe the animals eating, or moving or even interacting with other living things. But
what they can do is interpret how the animal lived by studying the fossil remains.
Like a palaeontologist would, study the skeletons below and interpret how they lived.
Genyornis
Megalania
Megalania
Genyornis
What kind of animal is this? How can
you tell?
What kind of animal is this? How can
you tell?
What did it eat? Why do you think so?
What did it eat? Why do you think so?
How did it move? Why do you think so?
How did it move? Why do you think so?
How fast do you think it moved? What
makes you say this?
How fast do you think it moved? What
makes you say this?
18
PrimeSCI! © 2015
Activity 7: Creative science writing
For this task you need to write a short story about:
'A Day in the life of an Australian Megafaunal Animal'.
Imagine you are an ancient animal from Australia - during the time of the megafauna (big
animals) around about 50,000 years ago! What would your day be like? What might
happen? Where do you live? Your 'story' can be presented in one of the following
formats of your choice:
* poem
* 'dear diary' entry
* creative story
* newspaper report
You need to apply your understanding of ancient animals in a creative way. While
you story is to be creative, you must also include scientific information about fossils.
You might choose to include information such as:
4What kind of animal are you?
4Where do you live? Which country do you live in?
4How many years ago did you live?
4What did you eat?
4What other kinds of animals might you have seen or interacted with during your day?
4Do you have predators?
4How did you die and become a fossil?
4Do you have any special features that help you survive in your environment?
Use the following website to find out information about the kinds of animal you might like to
chose:
8 http://www.abc.net.au/science/ozfossil/megafauna/fauna/fauna.htm
8 http://abc.net.au/beasts/
8 http://abc.net.au/science/ausbeasts/factfiles/
8 http://www.parks.sa.gov.au/naracoorte/wonambi/animals/extinct/index.htm
Here are animals you might like to chose that lived in Australia,
and became extinct about 50,000 years ago!
Diprotodon: a
giant wombat
that was about
2 meters tall.
Thylacoleo:
a marsupial lion that was the
largest meat eating
marsupial to have ever
lived in
Australia.
Procoptodon: a
giant short-faced
kangaroo that was 2
to 3 meters tall.
Megalibgwilia
ramsayi: a very
large long-beaked
echidna.
Megalania: a 6 meter
long giant lizard.
Genyornis: a 2 meter
tall flightless bird.
Wonambi: a 5 to 6
meter long snake.
19
PrimeSCI! © 2015
Part 5: Linking activities
Planning for learning requires the inclusion of explicit activities that 'focus on
building a richer meaning for the knowledge presented by the teacher by linking it to
elements of memory.” (p.187 Baird.J & Mitchell, I. 1995).
In this unit, concept mapping is used as a strategy to provide valuable feedback about the
effectiveness of the processing activities outlined earlier in the unit. The activity outlined
below allows the students to work in groups and explore all the possible links they can think
of between key concepts covered to date. How well students understand the content
covered to date may be reflected in the types responses each group composes.
Activity: Completing Statements from the Stem
Students complete responses to sentence stems. Some examples include:
$ We know about animals that lived in the past because……………..
$ Some fossils tell us that……………….
$ My favourite fossil was _________ because …………………
Students complete sentences and these are shared with rest of the class by displaying them
in a special area of the room. Students can be encouraged to go on a print walk and read
other students responses. For the younger students, the sentence stem can be written on
the board, and the teacher can list for the students all the ideas they have for sentence
endings.
Activity: Group Concept Maps
Concept mapping is a procedure that assists students in their understanding of the
connections between the major concepts in a content area. (Baird.J & Mitchell, I. 1995).
«Using key words from the topic list select 5 and paste on large cards.
fossil
«Place these cards on the floor in a random arrangement.
«Place students in teams of at least 4. Each team is given a piece of
streamer.
«The team must select two words from the floor ,and when it is their
turn they must place their strip of streamer between these cards and
dinosaur
explain their understanding of how these words could be linked.
«On a sheet of paper record the main ideas expressed (in key words)
and place this sheet on the piece of streamer.
«Continue until all groups have had a turn. If there are further ideas, continue again for
another round. This can also be completed on a pin board, and the results can be left on
display.
This activity provides informative feedback about how students are making sense of the
information which has been covered through the unit, and also exposes students to other
students' ideas.
20
Early Years Education Booklet
PrimeSCI! © 2015
What are fossils?
Fossils are the remains of once living organisms.
How do fossils form?
Fossils are usually found in sedimentary rocks.
Sedimentary rocks are often made up of
particles sand, silt or gravel. When an organism
dies, it may be covered by layers of sediment,
which later consolidate into sedimentary rocks.
Sediments are usually deposited in the bottom
of lakes, rivers or in the sea, or even from windblown sand dunes. These layers can sometimes
enclose the remains of the organism. If
conditions are right, the layers will consolidate
(solidify) into rocks, and the preserved remains
of the dead organism will become fossils.
How old is the Earth?
The Earth began to solidify and divide into its
layers, and have a solid surface, about 4.6
billion years ago, or in other words that's 4600
million years ago long, long ago!
When did life begin?
The oldest records of life on Earth are 3.8 billion
years old that's 3800 million years ago!
What did the first life look like?
Very small! Microscopic. The oldest life forms on
Earth were so small, to see them you would
need a microscope. These organisms were
single celled - made up of only one cell. We are
multicelled animals, made up of many cells.
When did the first vertebrate animals
appear?
The first fossils of backboned (vertebrate)
animals are Cambrian in age, dating back nearly
530 million years. These first vertebrates were
fish but fish that had no jaws.
Can fossils tell you the age of a rock?
Fossils can give a relative date, not a date in
years. Trilobites are found in rocks that lie
below those that contain dinosaurs, and so
trilobites lived before the dinosaurs. Trilobites
became extinct approximately 245 million years
ago, so if you find a rock with a trilobite in it you
know the rock must be older than 245 million
years old.
When did the biggest extinction event
occur?
The extinction of the dinosaurs at the end of
the Cretaceous time period (some 65 million
years ago) was nothing when compared to
what happened on Earth at the end of the
Permian about 245 million years ago. Some
palaeontologists have suggested that up to
97% of life was wiped out at that time. Life
was almost lost at the end of the Permian.
What happened to cause such a massive
wipe out of species at the end of the
Permian?
There are many theories, but for the moment
this is one of the big mysteries that is not so
well explained. In the millions of years before
the end of the Permian, there had been a
lengthy glaciation big ice sheets moved from
the north and the south affecting many
continents. So, times were cold. But during
the Permian, glaciation subsided and at the
end of Permian times there were great
volcanic outpourings and Earth may have
been blasted by a large meteorite!
With all the water tied up in ice, the sea level
was lowered and many of the areas of the
world that form the shallow marine waters
around the continents were laid bare. These
are areas where most marine animals today
thrive and would have in the Late Permian.
So, those shallow marine animals would have
been under great stress.
We know that the was vast volcanic activity
at this time would have thrown ash up in the
air which would have caused climatic change
that affected animals and plants the world
around.
And the recent evidence that a gigantic
meteorite hit Earth and caused rapid and
catastrophic climatic cooling, wildfires, acid
rain may well have also contributed to the
mass extinctions that occurred at this time.
Thankfully life survived - but maybe only just!
21
PrimeSCI! © 2015
What killed the dinosaurs?
The debate still rages between palaeontologists
as to what killed the dinosaurs, some 65 million
years ago, it may have been instantaneous or
prolonged over a period of hundreds of
thousands or possibly even a few million years.
At present, there are two main ideas about what
wiped out the dinosaurs.
Asteroids and comets?
One theory suggests that the extinction of the
dinosaurs was brought about by the impact of
an extraterrestrial object, a comet or an asteroid.
Such an impact could have brought about an
immediate rise in the surface temperature of the
Earth, causing widespread wildfires, dramatic
increase in global ocean temperatures, and a
short period of terrible acid rain. This short-term
event may have then been followed by a longer
term cooling of Earth temperatures because of
the dust particles kicked up in the atmosphere
by the impact, restricting the amount of sunlight
reaching the Earth's surface.
Volcanic activity?
A second theory about dinosaur extinction
suggests that intensive volcanic activity filled the
atmosphere with particles and reduced the
amount of energy reaching the surface of the
Earth from the Sun. Effects of even small
volcanic eruptions such as Krakatoa, Pinatubo or
Mount St Helens have shown a temperature
drop due to volcanism.
Or a double whammy?
Some scientists have suggested that perhaps
the impact of a comet or asteroid triggered
massive volcanic activity on Earth, such as that
in India at about this same time. In any case, the
biological consequence of one or both of these
events brought about a relatively rapid turnover
in the vertebrate and invertebrate fauna of the
Earth.
What happened to life on Earth after the
dinosaurs become extinct?
During the last 65 million years, once most
of the dinosaurs became extinct, the world
changed a great deal. From the warm
Greenhouse conditions of the Cretaceous
some 100 to 65 million years ago, the
Earth's climate began to cool. It was during
this time, without the dinosaurs that
mammals and birds, insects and teleost
fishes exploded into many different kinds of
new species.
The flora changed too. Plants bearing
flowers became dominant and so the whole
smell of the world changed from that of the
green conifer forests of the Mesozoic to the
blossom-bearing shrubs and trees that are
typical of today.
What is megafanua?
Megafauna is defined as reptiles, birds, and
mammals over 40 kilograms in weight.
During the Plesitocene Period (1.8 million
years to 10,000 years ago), Australia
supported a diverse assemblage of
megafaunal mammals such as Diprotodon,
megafaunal birds such as Genyornis, and
megafaunal reptiles such as Megalania.
Why did the megafauna in Australia
become extinct?
A few theories have been suggested as
possible explanations of what caused the
extinction of the megafauna of Australia.
Natural climate change is one theory, habitat
change resulting from human burning of the
bush is another, and hunting of the
megafauna by humans is yet another theory.
Were mammals living during dinosaur
times?
Yes, mammals lived and developed at the same
time as the dinosaurs. But as long as dinosaurs
were around, mammals were relatively small, and
probably nocturnal. Once the dinosaurs were
gone, mammals took over the world!
22
PrimeSCI! © 2015
Glossary
Absolute date:
a method which
determines the time order
in rock sequences,
measured in years by
radiometric techniques
that is, those techniques
which depend on the
regular and statistically
predictable decay of
radioactive elements
(Carbon14 for example).
Amphibian:
animals that live in water
and on land during their
life. However, some
amphibians were
completely aquatic and
some were completely
terrestrial.
Ancient:
old
Aquatic:
living in water.
Bacteria:
microscopic single-celled
organisms, they lack
chlorophyll, and they
reproduce by fission.
Biostratigraphy:
ordering of rock
sequences, to determine
their approximate age,
based on the fossils found
in the rock.
Carnivore:
an animal that eats mostly
meat.
Cell:
the smallest living unit that
makes up most living
things.
Character:
a distinguishing feature.
Conifer:
a plant that reproduces
through the production of
seeds in cones.
Cycad:
an ancient type of seed
plant that was around at
the dinosaurs, and still
lives today.
Deposit:
to lay down in one place,
eg: sediments are
deposited in lakes.
Erosion:
wearing away of the land
surface by the
transportation of debris by
wind or water.
Evolution:
changes over generations
in the characteristics of
plants and animals.
Fossil:
From the Latin word
meaning to "dig up". The
remains or impressions of
life, that lived in the past.
Gondwana:
a massive supercontinent
of the past, that included
South America, Africa,
Antarctica, Australia, New
Zealand, India, and
perhaps parts of China.
Glacier:
a large mass of ice on the
land or over a water body,
which moves in a definite
direction.
Habitat:
a place where an animal or
plant lives.
Herbivores:
an animal that eats mostly
plants.
Extinct:
no longer living on the
Earth.
Hibernate:
to pass the winter in a
torpid state. During this
state, the animal's
metabolism slows down
and there is no need to
eat.
Fauna:
animals living in one area
or at a particular time.
Invertebrate:
animal that has no
backbone.
Flora:
a group of plants living in
on area or at a particular
time.
Labyrinthodont:
crocodile-like amphibians
that lived before and along
side the dinosaurs.
23
PrimeSCI! © 2015
Glossary
Lungfish:
most of these fish breathe
in oxygen from the air
rather than taking it from
the water. They are a
particular group.
Mammal:
a group of vertebrates that
usually give birth to live
young. Mammals usually
have hair, are warmblooded, and feed their
young with milk.
Marsupial:
a mammal that gives birth
to its young at a very early
stage. The baby marsupial
crawls into the pouch and
grabs onto a teat where it
stays, drinking milk, for a
while, until developed
enough to get about on its
own.
Megafauna:
very large animals,
generally animals that
weigh more than 40
kilograms.
Vertebrate:
Animals with a backbone.
Meteorite:
a solid body from outer
space; there are two kinds;
- those that are mostly
stone and those that are
mostly iron.
Multicelled:
many cells, an animal that is
multi-cellular is made up of
more than one cell.
Nocturnal:
active at night.
Organism:
a living bacteria, plant, fungi
or animal; they can
duplicate itself.
Omnivore:
an animal that eats both
plants and meat; thus has a
varied diet.
Plesiosaur:
an extinct group of seadwelling reptiles.
Plesiosaurs had a barrelshaped body, a short tail
and paddle-like limbs
perfect for swimming.
Placental Mammal:
mammals that give birth to
highly developed young,
with a specialised tissue the placenta - which
nourishes the developing
embryo.
Reptile:
a group of vertebrates (have
a backbone), which are
covered by scales, and lay
eggs on land to reproduce.
Sedimentary Rocks:
rocks formed of sediments
deposited by water or air,
e.g.: claystone, sandstone,
siltstone or conglomerates.
24
Sediments:
the grains and organic
debris that are the result
of rocks weathering
(breaking down) and the
'debris' being transported
by wind and water, laid
down in some kind of
sedimentary environment
(e.g.: a lake, ocean or
sand dune).
Skeleton:
the bones that make up
the internal structure of a
vertebrate animal, or the
external covering of an
invertebrate animal (such
as a crab shell).
Solidify:
to become solid or firm.
Species:
a unique kind of animal or
plant, e.g.: Homo sapiens
(the scientific name for
humans).
Weathering:
the break down of rocks
into smaller pieces by
exposure to wind, water,
sun, heat, cold and
chemicals.
Vegetation:
plants growing in a place.
e.g.: all of the plants
growing in Southeast
Australia.
PrimeSCI! © 2015
Resources
Web Sites
http://primesci.monash.edu
This is the website for PrimeSCI! (previously the Monash Science Centre) at
Monash University.
http://www.dinosaurdreaming.net/
This is the official site of the dinosaur dig in Victoria. This site gives excellent information
about the Inverloch dinosaur dig and the dinosaurs found there. It also has links to other
dinosaur sites around the world.
http://www.abc.net.au/dinosaurs/
This site has more information about Australian dinosaurs from around the world.
http://www.nhm.ac.uk
The Natural History Museum, London site has data files on the most well known dinosaurs,
plus it has great suggestions for classroom activities on dinosaurs.
http://www.ucmp.berkeley.edu/fosrec/Learning.html
This sites lists classroom activities on dinosaurs and fossils. It also has excellent interactive
lessons online, including topics such as geological time.
http://www.dinosaurvalley.com/activity_guide/
This site contains free pictures of dinosaurs to colour in. You could print out some of
the pictures and make dinosaur jig-saw puzzles of your own.
http://www.museum.vic.gov.au/dinosaurs/
The Museum Victoria fossil project web site. This site contains lots of information on fossils,
fossilisation, megafauna and dinosaurs.
http://www.oum.ox.ac.uk/thezone/fossils/games.htm
http://www.sdnhm.org/exhibitions/current-exhibitions/fossil-mysteries/
Interactive activities for students about fossils.
http://www.nhm.ac.uk/nature-online/evolution/
Watch a short video on the evidence for evolution
http://www.abc.net.au/science/ausbeasts/
Information and games about Megafauna.
http://www.monash.edu/science/research-groups/earth-atmosphere-environment/precsite
Information about Precambrian life and environments.
25
PrimeSCI! © 2015

Wildlife of Gondwana

Transcription

Similar documents

Untitled

Wildlife of Gondwana

Study Guide For Pre K- 3rd Grades

Program objectives: Program overvieW

Creating Good Memories through Music and promoting international

Dinosaur Footprints

April 2013 - Thunderbird Preschool

Discovering Dinosaurs