can you run on your fingernails?

Can you run on your fingernails?

B1b7.1

Can you run on your fingernails?

Can you run on your fingernails?

UPDATE: Katie (Fellow blogger) tells me those nails are probably fake—which doesn't reduce the yuck factor by much for me.

Discussion

• Do you think any living thing could run on its finger nails?

• A mouse?

• A human?

• A horse?

• Discuss this for 2 minutes in pairs

Horses – 55 million years ago

• Hyracotherium

• Look at its feet

Fossils of Hyracotheriums foot!

• It ran on 4 toes – why do you think it did that?

Here’s where it lived

• Soft marshy ground

Horses 37 million years ago!

• Mesohippus

• How many toes?

Horses - 25 million years ago

• Merychippus

• Look at the toes?

• What’s happened?

Horses - 5 million years ago

• Pliohippus

• What has happened to the side toes?

Horses - now Equus (horse)

It has a hoof made of one toe only – and the nail of the toe is on the bottom

So…..horses can run on their toenails!!

Horses

today ->

What were those things we were just looking at?

• And on the background of this slide…..

What were those things we were just looking at?

• Fossils

What were those things we were just looking at?

• Fossils

• So what are fossils

• Discuss what you know for 1 minute.

Feedback – what do we know about fossils?

What do we know about fossils?

• By the end of this lesson we will….

• All be able to explain what a fossil is

• Mostly be able to explain how they are formed and

• Some of us will be able to explain what they can teach us

What is a fossil?

• Most fossils are formed when the hard parts of an animal or plant that has died are replaced by other minerals. This takes many years.

Making a fossil 1• To start with an animal or plant must

die in water or near enough to fall in shortly after death. The water insulates the remains from many of the elements that contribute to decomposition. In the following example a trilobite has died of old age on the bottom of the sea. Bacteria consume the soft body parts but leave the hard exoskeleton intact.

Making a fossil 2• Sedimentation

As time passes sediments bury

• the exoskeleton. The faster this happens the more likely fossilization will occur. As the sediments continue to pile on, the lower layers become compacted by the weight of the layers on top. Over time, this pressure turns the sediments into rock.

Making a fossil 3• If mineral-rich water percolates

down through the sediments, the fossilization process has an even better chance of preserving our ancient animal. Over the course of millions of years they dissolve away the outer shell, sometimes replacing the molecules of exoskeleton with molecules of calcite or other minerals. In time the entire shell is replaced leaving rock in the exact shape of the trilobite.

Finding our fossil • Plates move the Earths surface• Weather erodes it away

Our fossil!

What is a fossil?

• Most fossils are formed when the hard parts of an animal or plant that has died are replaced by other minerals.

• Some fossils form when whole organisms die but don’t decay. Sometimes the temperature was too low or there were no bacteria

Fossils preserved in peat

• These beetle wings have been perfectly preserved

• They are from 10 000 b.c.

Fossils preserved in ice

• Fossils of an ancient fish - dating back 450 million years, when the creatures had neither bones nor teeth - have been found in South Africa. The finds, which are 50 million years older than any other fossil fish in Africa, will help provide a "missing link" in the evolution of early fish.

What is a fossil?

• Most fossils are formed when the hard parts of an animal or plant that has died are replaced by other minerals.

• Some fossils form when whole organisms die but don’t decay.

• Some fossils are of the traces that plants or animals leave behind

Trace fossils

• Ardley quarry in Oxfordshire

Trace fossils

• An imprint of a living thing

• There are also fossils of droppings as well as foorprints

A quick test!

Which are body fossils are which are trace fossils?

Just list A – G in the back of your book and write B or T next to each one

Answers

Answers A. body fossil, B. B. trace fossil, C. C. body fossil, D. D. body fossil (both the

fossil animal in the egg and the egg itself),

E. E. trace fossil, F. F. trace fossil, G. G. body fossil.

What is a fossil?

• Most fossils are formed when the hard parts of an animal or plant that has died are replaced by other minerals.

• Some fossils form when whole organisms die but don’t decay.

• Some fossils are of the traces that plants or animals leave behind

What is a fossil?

• Write your own quick explanations of what the three types of fossil are and how they are formed

What’s the oldest fossil ever found?

• How would you find out?

What’s the oldest fossil ever found?

• Sign in   Web    Images    Groups    News    Froogle    more »  Advanced Search  Preferences    Google SafeSearch is ONSearch: the web pages from the UK  Web Results 1 - 10 of about 4,040,000 for oldest fossil with Safesearch on. (0.37 seconds) 

• [PDF] Oldest Fossil Found in Michigan File Format: PDF/Adobe Acrobat - View as HTMLOldest Fossil Found in Michigan. Photograph of a specimen from Negaunee. The Negaunee Iron formation near Palmer. in the Northern Peninsula is the home of ...www.deq.state.mi.us/documents/deq-glm-rcim-geology-Oldest_Fossil.Pdf - Similar pages

• BBC NEWS | Science/Nature | Oldest fossil 'rabbit' unearthed The fossilised skeleton of a rabbit-like creature that lived 55 million years ago is found in Mongolia.news.bbc.co.uk/2/hi/science/nature/4274129.stm - 30k - Cached - Similar pages

• BBC News | Sci/Tech | Oldest fossil fish caught Chinese palaeontologists say they have discovered two new species of fish that once swam in the oceans 530 million years ago.news.bbc.co.uk/1/hi/sci/tech/504776.stm - 19k - Cached - Similar pages

• Earth’s Oldest Fossils Reverse Course It’sa critical question of life science: Are microscopic structures found in 3.5 billion-year-old Archean rocks from Western Australia the oldest fossils of ...

Why are we interested in fossils?

• Sign in   Web    Images    Groups    News    Froogle    more »  Advanced Search  Preferences    Google SafeSearch is ONSearch: the web pages from the UK  Web Results 1 - 10 of about 4,040,000 for oldest fossil with Safesearch on. (0.37 seconds) 

• [PDF] Oldest Fossil Found in Michigan File Format: PDF/Adobe Acrobat - View as HTMLOldest Fossil Found in Michigan. Photograph of a specimen from Negaunee. The Negaunee Iron formation near Palmer. in the Northern Peninsula is the home of ...www.deq.state.mi.us/documents/deq-glm-rcim-geology-Oldest_Fossil.Pdf - Similar pages

• BBC NEWS | Science/Nature | Oldest fossil 'rabbit' unearthed The fossilised skeleton of a rabbit-like creature that lived 55 million years ago is found in Mongolia.news.bbc.co.uk/2/hi/science/nature/4274129.stm - 30k - Cached - Similar pages

• BBC News | Sci/Tech | Oldest fossil fish caught Chinese palaeontologists say they have discovered two new species of fish that once swam in the oceans 530 million years ago.news.bbc.co.uk/1/hi/sci/tech/504776.stm - 19k - Cached - Similar pages

• Earth’s Oldest Fossils Reverse Course It’sa critical question of life science: Are microscopic structures found in 3.5 billion-year-old Archean rocks from Western Australia the oldest fossils of ...

Why are we interested in fossils?

• Any ideas?

Why are we interested in fossils?

• They might be able to tell us how old the Earth is

• They will be able to tell us how plants and animals have changed over many years

• This will give us some ideas about how the climate on the Earth also changed

• Why might this be useful information?

Interactive Timeline

• Watch carefully

• Look out for when the humans arrive!

So how old is the Earth

• What’s your best guess?

• How could we find out?

So how old is the Earth

• Somewhere between 3500 and 4500 million years!!

• What’s that in billions

• How many seconds is that!

• How many life times is that?!

Plenary

• Why are there hardly any fossils of worms?

• How have fossils helped us understand where we come from?

• Have they told us everything about where we come from?

• Why can’t we be certain when life began?