Keystone Species and Beavers

The video explains the concept of keystone species, focusing on beavers as an example. Keystone species have a significant impact on their ecosystems, similar to how a keystone holds an arch together. Beavers create wetlands by building dams, which increases biodiversity. Their activities change the distribution of plants and animals, affecting the ecosystem's structure. Beavers are adapted to aquatic life, and their presence can indicate the health of an ecosystem. The video concludes by highlighting the importance of keystone species in maintaining ecological balance.

What is a keystone species?

• A species that is the largest in its habitat

• A species that has a minimal impact on its ecosystem

• A species that significantly influences its ecosystem

• A species that is always at the top of the food chain

Why are beavers considered a keystone species?

• They eat a wide variety of plants

• They are the fastest swimmers in their habitat

• Their dam-building activities create wetlands

• They are the largest rodents in North America

How does the presence of beavers affect biodiversity?

• It only affects plant species

• It increases biodiversity

• It has no effect on biodiversity

• It decreases biodiversity

What happens to the ecosystem when the number of beavers decreases?

• Biodiversity decreases

• New species are introduced

• Biodiversity increases

• The ecosystem remains unchanged

How do beavers adapt to their aquatic environment?

• They can breathe underwater

• They can stay underwater for up to 15 minutes

• They can fly short distances

• They have webbed feet for walking on land

What is the effect of beavers cutting down trees?

• It creates gaps for new plant growth

• It leads to deforestation

• It reduces the number of tree species

• It causes soil erosion

Which animals benefit from the ponds created by beaver dams?

• Only fish

• Only birds

• A variety of animals including amphibians and reptiles

• Only mammals

How do beavers influence the types of trees in their habitat?

• They do not affect tree species

• They select specific trees, altering the forest composition

• They only cut down dead trees

• They plant new trees

What role do beavers play in determining ecosystem health?

• They only affect water quality

• They are indicators of ecosystem health

• They are a nuisance to ecosystems

• They have no role in ecosystem health

What is a unique characteristic of beavers in North America?

• They are the smallest rodents

• They are known for their speed

• They are the most colorful animals

• They are the largest rodents