![A forest damaged by pine beetles](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/pine-beetle-damage-forest.jpg?itok=rD_omerz)
How Do Introduced Species Affect Ecosystems and the Economy?
STEM Explained
When a species ends up outside of its natural zone, the consequences on other species, ecosystems and human industries can be severe. Climate change and human activities can introduce species into new zones.
![How do movies move?](/sites/default/files/2019-08/how-do-movies-move.jpg)
How do movies move?
Hands-on Activities
Explore the concept of persistence of vision in this hands on activity.
![Lawn mower mowing grass](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/image%2C.jpg?itok=7Rfn7uh2)
How Do Plants Use Chemical Signalling?
STEM Explained
How do plants use scents? Learn how some plants use chemical signals to send messages to animals or other plants.
![Colourful sunglasses](/sites/default/files/styles/resource_card_image_360x300_/public/2021-03/colourful_sunglasses.jpg?itok=mZ_pixQ-)
How Do We See Colour?
STEM Explained
How does the human eye see visible light as colour? And why do some people see more colours than others?
![Bird near a wind farm](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/western-kingbird-and-wind-turbine-farm.jpg?itok=o-qeejDW)
How do Wind Farms Affect Birds and Bats?
STEM Explained
Wind energy generates a lot of electricity in Canada. But wind turbines can be dangerous for wildlife.
![bees on frame held by beekeeper](/sites/default/files/styles/resource_card_image_360x300_/public/2019-11/Bees_at_work.jpg?itok=eCBFpn4d)
How are the World's Bee Populations Doing?
STEM Explained
Bees are important for agriculture. But bee populations face threats. This resource looks at Colony Collapse Disorder, herbicides & pesticides, and more.
![How big were dinosaurs?](/sites/default/files/2019-08/how-big-were-dinosaurs.jpg)
How big were dinosaurs?
Hands-on Activities
Some dinosaurs were very big! Compare the sizes of different dinosaurs to the sizes of familiar objects you see in your community.
![Salmon aquaculture pens](/sites/default/files/styles/resource_card_image_360x300_/public/2020-05/Salmon_aquaculture_pens.jpg?itok=yrwdnv2j)
Farmed Salmon vs. Wild Salmon
STEM Explained
Aquaculture is seen as a sustainable way to produce fish. But are farmed salmon better than wild fish?
![Canaries were once used to signal dangers to miners. - Image © Vito Cangiulli, iStockPhoto.com](/sites/default/files/styles/resource_card_image_360x300_/public/2019-09/Canaries%20were%20once%20used%20to%20signal%20dangers%20to%20miners.jpg?itok=mc-wHhjT)
How Can Birds Help Monitor the Health of Ecosystems?
STEM Explained
Scientists can observe birds to get useful information about the health of, and changes in, an ecosystem.
![Goldfish Goldfish](/sites/default/files/styles/resource_card_image_360x300_/public/Gullfiskur.jpg?itok=L6czSzoc)
Fish: Freshwater
Picture Collections
4 images of some fish such as koi that live in freshwater river and lake environments and in freshwater aquariums and garden ponds
![Clown Fish Clown Fish](/sites/default/files/styles/resource_card_image_360x300_/public/Clown_fish_in_the_Andaman_Coral_Reef.jpg?itok=nkTzBh1T)
Fish: Saltwater
Picture Collections
14 images of some fish such as lion fish, grouper and sharks that live in saltwater environments like oceans, saltwater lakes and aquariums
![Water Lily Water Lily](/sites/default/files/styles/resource_card_image_360x300_/public/waterlily.jpg?itok=nnvmuAjZ)
Flowers: Cup Shape
Picture Collections
8 images of some flowerheads such as roses and water lilies whose outer petals are longer than the petals in the centre of the flower
![Iris Iris](/sites/default/files/styles/resource_card_image_360x300_/public/blueiris.jpg?itok=dvud8S14)
Flowers: Irregular Shape
Picture Collections
3 images of some asymmetrical flowerheads such as an iris and an Orchis Sima or Monkey Orchid
![Sunflower Sunflower](/sites/default/files/styles/resource_card_image_360x300_/public/sunflowers.jpg?itok=pmiRVO51)
Flowers: Radial Shape
Picture Collections
7 images of some symmetrical flowerheads such as asters and sunflowers whose petals radiate from the centre of the flower
![Petunias Petunias](/sites/default/files/styles/resource_card_image_360x300_/public/petunias.jpg?itok=yMPRRNyK)
Flowers: Trumpet Shape
Picture Collections
5 images of some flowerheads such as petunias and lilies that start as a narrow base and widen to an open shape