Q 01/05

Blue whales, the largest animals ever known, feed almost entirely on which swarming crustaceans?

A) Copepods

B) Barnacles

C) Krill

D) Amphipods

Answer · why

C) Krill

Krill make up almost the whole diet of the blue whale, which lunges into a swarm at speed with its mouth gaping up to 80 degrees and strains them from...

Q 02/05

Giant pandas belong to the meat-eating order Carnivora, yet about 99% of their diet is which plant?

A) Bamboo

B) Sugarcane

C) Rhododendron

D) Mulberry

Answer · why

A) Bamboo

Bamboo gives a giant panda little energy, because the animal still has the short, straight gut of a carnivore and so has to eat enormous amounts of it...

Q 03/05

Which bog plant, native only to the Carolinas, flips the food chain by snapping shut on insects?

A) Butterwort

B) Purple pitcher plant

C) Bladderwort

D) Venus flytrap

Answer · why

D) Venus flytrap

The Venus flytrap shuts only when two of its trigger hairs are touched within about twenty seconds, a check that stops it wasting effort on raindrops.

Q 04/05

Which mammal guards Pacific kelp forests by eating the sea urchins that graze them bare?

A) Sea lions

B) Sea otters

C) Walruses

D) Harbor porpoises

Answer · why

B) Sea otters

Sea otters eat so many sea urchins that their teeth and bones can be stained purple, and where they vanish the urchins can mow whole kelp forests down...

Q 05/05

Which predators, back in Yellowstone since 1995 after nearly seventy years away, prey mainly on elk?

A) Gray wolves

B) Mountain lions

C) Coyotes

D) Wolverines

Answer · why

A) Gray wolves

Gray wolves were released in the Lamar Valley, and as their packs grew the elk herds shrank, easing the browsing pressure on the willows and aspens.