Produced by Claire L. Evans for Darwin 200

By condensing 4.6 billion years of history into 60 seconds, the video is a self-contained timepiece. Like a specialized clock, it gives a sense of perspective. Everything — from the formation of the Earth, to the Cambrian Explosion, to the evolution of mice and squirrels — is proportionate to everything else, displaying humankind as a blip, almost indiscernible in the layered course of history.
We have added this video to the 'extension' ideas of our Earthlearningidea 'A time-line in your own backyard'

Physical weathering - cracking apart

This is our latest ELI+ activity 'Cracking apart; simulating the weathering of rocks in a desert environment'
Ask pupils to discuss situations where materials expand in the heat and contract in the cold out of doors. Examples might include steel bridges, or concrete roads; in both cases, expansion joints have to be included to allow for the movement. Explain that rocks also expand and contract and that this can lead to their break up. This is a form of physical weathering.
Ask them to investigate how quickly a small granite chip breaks up when it is first held in a Bunsen flame until it glows and is then dunked in a beaker of cold water. Small groups could be challenged to see which is the first group to get its granite chip to break up.
The Earthlearningidea website has lots of ideas for practical science or geography activities.

What was it like to be there?

Have you tried this Earthlearningidea? 'What was it like to be there? - bringing a fossil to life'
What sort of place was the animal shown in the photo living in? It had feet, so must have lived on land and there must have been other animals around for it to eat — and they must have eaten plants.
What did it breathe? It lived on land, breathing the oxygen in the air as we do.
What did it eat? Its sharp teeth show it was a meat-eater.
Was it a hunter? — or hunted? — or both? The teeth are those of a hunter.
What could it have seen? It could have seen its prey — especially plant-eating dinosaurs, and the plants that they lived on.
What could it have sensed? It would have all the senses that we do.
How did it die? — can we tell? This well-preserved skeleton shows that the animal must have died suddenly and been buried by muddy sediment. The tightening of the neck muscles after death caused its head to bend backwards.
What happened after it died? The soft parts rotted and disappeared and the surrounding sediment hardened into rock, preserving the bones.
This is one of many Earthlearningidea activities about fossils which are popular with pupils. Have you tried the others?

ELI+ for 2010

We shall be publishing new Earthlearningideas every two weeks throughout 2010. Some of these activities will require the use of some basic school laboratory equipment and some will include more abstract ideas than we have considered in the past. We will label these activities ELI+.
We are launching the new activities with 'The watery world of underground chemistry - using pH to link the atmosphere, hydrosphere, biosphere and lithosphere together' The activity involves a discussion, with demonstrations, of the likely change in pH of water as it goes through the underground part of the water cycle.
Please do try it with your pupils and let us know how they get on. This is the 70th activity on the website so there are plenty to choose from.