Category: Natural World

Class Insecta

Dragonfly in flight. Image by Luc Viatour.

Since we’re focusing on the life sciences this year I want to complete the nature trail. Part of this project is to catalog the biodiversity on the trail. I’d like to have students specialize on the different types of organisms we find. Undoubtedly, the Class Insecta will be well represented. The site, Entomology for Beginners is a great basic resource. It starts with very simple cartoons of insect parts but also has a great key to insect orders which walks you through the comparisons you need to make to identify the Orders in which a particular insect belongs.

The site also has a page on simulating the dynamics of insect populations using a simple model. This may be for the more advanced student however.

A more general guide to bugs (Phylum Arthropoda) can be found at Bug Guide. Their Clickable Guide to the left of the page is a great starting place.

Insect. Image by Luc Viatour.

Luc Viatour has a large gallery of macro images of members of the Phylum Arthropoda.

Timeline of life

Timeline of Life on Earth.

This year the theme is life. My central organizing structure is the timeline of life on Earth. I plan to link all of the discussions of taxonomy, phylogeny and genetics to this timeline over the course of the year.

The timeline above will be the first lesson. As with these things the trick is deciding how much detail to keep in and how much to keep out.

What I like is that it gives the general overview of when important things happen while leaving a lot of space for students to investigate. Most of what we’ll be seeing this year happened in the Cambrian and this timeline conveys that this is a very small part of the whole history of life. In fact, it’s only when we cover the biochemistry of genetics that we will be talking about the origins of life.

From the Exploring Earth's Origins website.

The website Exploring Life’s Origins has a great timeline. It also has some really neat sections, with very useful videos, on the formation of protocells and the origin of RNA on the early Earth that lead to life as we know it.

The Magnetic Field?

The one thing I left out that I’m still conflicted about is the Earth’s magnetic field. Recent research indicates it has been around since 3.2 billion years ago and its presence or absence may have had profound effects on life.

The Earth's magnetic field protects us from the solar wind. Image from NASA.

Having a magnetic field protects the Earth from the charged particles spewing out of the Sun, the solar wind. This makes life on land a lot easier since the solar wind’s particles are quite damaging to DNA. However, prior to the magnetic field forming all this damage to DNA may have also accelerated mutation and thus evolution.

Insects up close

Photo by Luc Viatour from the Réserve naturelle Marie-Mouchon.

A change of perspective can give the most amazing insights. I find macro photographs, particularly of insects, to offer a stunningly refreshing view of these nuisances. Luc Viatour, whose image is posted above, has some wonderful, copyright permissive, pictures.

Alternatively, Miroslaw Swietek has some amazing images of insects covered in droplets of dew (taken at around 3:00 am).

John Kimbler also has some spectacular photos as well as a nice article on how to do macro photography. The Wikipedia page on macro photography is also quite useful in that it goes into how to adapt your camera to take these photographs.

Photography, with it extensive use of refraction and reflection is a great avenue to talk about waves and their properties. Macro photography can be quite effective at striking the imagination and getting into taxonomy and entomology.

Help with gardening/greenhouse

The National Gardening Association website has a wealth of resources for managing a garden. Including regional reports:

For the middle-south, “With year’s hottest and driest weather just ahead, it is best to delay the planting of tress and shrubs until autumn, when the odds of successful establishment are more favorable.” – St. Claire, 2010

They also have some nice how-to videos and instructional pages on topics like planting tomatoes and starting vegetable seeds (for the plant sale).

Maps of wealth and population

World population in 2000. (© Copyright SASI Group (University of Sheffield) and Mark Newman (University of Michigan).)
Wealth in 2002. Copyright SASI Group (University of Sheffield) and Mark Newman (University of Michigan).

In the coming year we’ll be looking at inequalities in wealth around the world. One way of looking at this is via the two maps above from the WORLDMAPPER website. Countries are scaled by the population, in the first image, and wealth in the second.

Worldmapper also has quite the number of very interesting maps, including maps related to health, violence, pollution, food and ecology. The species at risk map ties in well with the study of the Earth’s resources.

They also distribute some animated maps as well as free software, called ScapeToad, that you can use to make your own maps. I like the fact that their maps and software are clearly licensed and allow free educational use.