200-year-old
fossil mystery resolved
Scientists
have reconstructed how an ancient reptile swam in the oceans
at the time of the dinosaurs.
Discussion
- What dinosaurs do you know of?
- What's your favourite dinosaur?
- When were they alive on earth?
- Have you ever been to a dinosaur museum?
- What's your favourite dinosaur movie?
- What do you know of the Loch Ness Monster?
New
Words:
plesiosaur (n) a limb (n) gait (n)
unveil (v) palaeontologist (n) Jurrassic (adj)
Read the article and answer this question:
1. What is it about?
Computer
simulations suggest the plesiosaur moved through the water
like a penguin, using its front limbs as paddles and back
limbs for steering.
The
creature's swimming gait has been a mystery since bones of the
first known specimen were dug out of a Dorset cliff 200 years ago.
Watch the video of how it moved here.
The
plesiosaur was discovered by the fossil hunter Mary Anning in 1821.
At
the time even the name dinosaur had not been invented.
A
scientific paper unveiling Anning's find a few years later
raised the question of how the marine creature swam, given its
unusual pairs of wing-like flippers.
The
debate has continued until today, with a computer simulation based on
a Jurassic fossil specimen providing evidence in favour of
penguin-like motion.
Dr
Adam Smith of Nottingham Natural History Museum, Wollaton Hall,
worked on the study.
He
explained that palaeontologists were divided on whether the
marine creature used its four limbs in a rowing action like the oars
of a boat; a flight stroke similar to modern penguins and turtles; or
some sort of combination of the two.
"Our
study shows the up-and-down movement is more likely," he told
BBC News.
"That's
how turtles and penguins swim today.
"Penguins
are literally flying through the water."
The
study, published in the scientific journal PLOS
ONE,
is based on a computer simulation of a Jurassic
fossil from Germany.
The
fossil is unusual in being an almost complete skeleton with all four
limbs preserved.
It
is smaller than many other members of the plesiosaur family, at about
3m long.
The
computer model shows the animal's hind limbs provided
"relatively weak thrust", say Dr Smith and co-researchers
at the Georgia Institute of Technology in Atlanta, US.
"We
conclude that plesiosaurs were forelimb-dominated swimmers
that used their hind limbs mainly for manoeuvrability and
stability," they report.
The
plesiosaurs were predatory marine reptiles that lived at the time of
the dinosaurs.
They
are unique in the animal kingdom for having two pairs of large
wing-like flippers.
Palaeobiology
expert Dr David Martill of the University of Portsmouth said the new
work suggested that in the small plesiosaur at least, the forelimbs
did all the work.
He
said it remained to be seen if the same was true of the largest
plesiosaurs, which were ferocious marine predators.
"These
beasts probably fed by twist feeding like the large crocodiles of
today," he said.
"If
this were the case, then the hind limbs may have been used to spin
the animal on its long axis."
Questions:
1.
When were the bones of the first specimen found?
2.
Who found them and where?
3.
Why is the time of this finding especially interesting?
4.
What two ways of swimming were suggested to be the way of motion
through water of the dinosaur?
5.
Which way is chosen by Dr Adam Smith of Nottingham Natural History
Museum?
6.
What is special about the fossil found in Germany?
7.
What does the computer model show?
8.
Is this the same for small and large plesiosaurs?
9.
How is it thought that they feed?
Discussion / Writing Ideas
1. Write a story abut a dinosaur set in modern day. How did it get here? What happens? How many people does it eat? Can it get home? Happy or sad ending?
2. Do you think we will ever be able to clone dinosaurs like in the movie Jurassic Park? Do you think we should, or not?
3. Do you think the Loch Ness Monster may have been a plesiosaur?
Discussion / Writing Ideas
1. Write a story abut a dinosaur set in modern day. How did it get here? What happens? How many people does it eat? Can it get home? Happy or sad ending?
2. Do you think we will ever be able to clone dinosaurs like in the movie Jurassic Park? Do you think we should, or not?
3. Do you think the Loch Ness Monster may have been a plesiosaur?
