Paul Andersen Paul Andersen

Desert Beetle Harvests Water

Description:  Certain species of darkling beetles that live in the Namib Desert are able to harvest water vapor using an ingenious series of tips and bumps on their wing scales. The water droplets start to form on the tips and then flow off the waxy bumps to be collected by the beetle. This structure allows the beetle to survive in an incredibly arid environment. It could also be used by engineers to develop a similar system for collecting water for humans. Students should use this and other plants and animal phenomenon to start designing their own solutions to human problems.

Web Resource: Water Vapor Harvesting - Ask Nature, Darkling Beetles  

Namib desert beetles live in an area with little ground water, so how is it that they have no trouble finding H2O? Find out how the resourceful insects use their wing scales to absorb water droplets from fog, and how we can use them as a model for combating water shortages.
 
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Paul Andersen Paul Andersen

The Asteroid That Killed The Dinosaurs

Description:  It is estimated that 75% of plant and animal (including dinosaur) species went extinct after the Earth was hit with a massive asteroid 66 million years ago. Evidence includes a thin layer of rock containing iridium (rarely found on Earth but common in asteroids) around the planet. Scientists have also discovered a large impact crater. The cause of the extinction is fairly clear but the details of the effects leave much to be explored.

Web Resource:  Cretaceous–Paleogene extinction event - Wikipedia

Ever wonder why the dinosaurs disappeared? HHMI BioInteractive investigates the cause of the mass extinction at the end of the Cretaceous period-and the clues come from paleontology, chemistry, physics, and biology. This three-act film tells the story of the extraordinary detective work that solved one of the greatest scientific mysteries of all time.
 
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Paul Andersen Paul Andersen

Megafauna Extinction: Humans or Climate?

Description:  North America (like Africa today) was once covered with large megafauna (animals weighing more than 100 pounds). This included giant mammoths, ground sloths, and beavers the size of a large bear. However most of these animals disappeared by 11,000 years ago. What was the cause of this extinction? Humans, climate, or a combination of the two? Phenomenon like this can be found around the World and can introduce the idea of human impacts on the environment.

Web Resource:  What Killed the Great Beasts of North America?

Complete video at: http://fora.tv/2010/05/18/Dr_Elizabeth_Hadly_Mammals_and_Climate_Change Stanford biologist Elizabeth Hadly recaps a debate among biologists over whether prehistoric megafauna like mammoths, giant sloths and saber-toothed cats became extinct due to overhunting by humans, or by a combination of hunting and a changing climate.
 
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Paul Andersen Paul Andersen

Exploring Microhabitats

Description:  Microhabitats can be found anywhere and they can lead to amazing exploration and discovery. An overturned decomposing log or the underside of a rock in a stream are excellent examples of microhabitats. Both a habitat and a microhabitat have typical abiotic (e.g. water, temperature, light. etc.) properties and biotic (e.g. plants, animals, fungi, etc.) factors. The nice thing about a microhabitat is that it is more accessible and a diversity of life can be found in an area that is not very diverse. If microhabitats are not available locally you can create one in your classroom. A terrarium or an aquarium is a great example of a microhabitat.

Web Resource: Microhabitats - Wikipedia

This video shows many animals that live in the microhabitats under logs. It can be used with NEXT GENERATION SCIENCE STANDARD 2-LS4-1.
 
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